SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO COLORADO
700 AM MDT SAT JUN 26 1999
I UPDATED ZONES ON THE SOUTHEAST EASTERN PLAINS AND SOUTHEAST
MOUNTAINS TO INCREASE CHANCES OF THUNDERSTORMS. NEW RUC IS SHOWING
THAT LOW LEVEL MOISTURE WILL BE MOVING FURTHER WEST AND SOUTH THAN I
EXPECTED EARLIER. ONCE CONVECTION GETS STARTED OVER EASTERN PLAINS
AND MCS POSSIBLY DEVELOPS...OUTFLOWS MAY PUSH MOISTURE FURTHER WEST
AND SOUTH. SLIGHT RISK OF SEVERE EXTENDS INTO KIOWA AND PROWERS
COUNTIES AND THIS IS MENTIONED IN SIGNIFICANT WEATHER OUTLOOK.
OUTSIDE THESE REGIONS...STRONGEST STORMS WILL BE OVER MONUMENT
RIDGE.
REGION ON SOUTHEAST PLAINS LEAST LIKELY FOR STRONG THUNDERSTORMS AND
AREAL COVERAGE IS ZONE 77.
.PUB...NONE.
WOLYN
FXUS65 KGJT 260916 co
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
910 PM EDT SAT JUN 26 1999
SFC RIDGE OVER THE REGION AND A WEAKENING AREA OF RAIN AND ISOLATED
TSRAS STRETCHING FROM CROSS CITY TO NEAR JESUP. IR SATELLITE IMAGES
SHOW MOST INTENSE ACTIVITY LOCATED OVER GA IN OUR CWA AND LIGHTNING
PLOTS SHOW JUST A FEW STRIKES WITH THIS CONVECTION. SFC ANALYZED
MOISTURE FLUX CONVERGENCE OVER THE FL PANHANDLE FAIRLY REPRESENTED
BY THE ETA AND RUC MODELS. BY AROUND 05Z-10Z...SOME OF THE
CONVECTION ASSOCIATED WITH THUNDERSTORMS AND SHOWERS OVER FL
PANHANDLE WILL PROBABLY MOVE INTO THE W OR SW PORTION OF THE CWA.
RUC ALSO INDICATES LOW LEVEL CONVERGENCE ENTERING THE SW CWA
TONIGHT. THE 00Z SOUNDING SHOWS PW OF NEAR 2.1 INCHES...LI IS
-3...CAPE IS NEAR 800 J/KG. THEREFORE FOR THE UPDATE...WILL KEEP IN
A CHANCE OF POPS W PART AND SLIGHT CHANCE ALONG THE COAST. TEMPS
LOOK FINE.
02
FXUS62 KJAX 270114 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN, FL
815 PM EDT SAT JUN 26 1999
CURRENTLY: LRG AREA OF SHWRS AND EMBEDDED TSTMS CONTINUES FM NNE TO
SSW BTWN POLK CO AND LEE CO. RAFL INTENSITY GENERALLY LIGHT TO
MODERATE WITH STILL THE POTENTIAL FOR LOCAL RATES OF 1 INCH PER HOUR
UNTIL 9 PM. AT THE SFC...USUAL AFTN TROF INITIALLY SET UP FM SE TO
NW ACRS THE CWA BUT HAS PROBABLY DISSOLVED IN RAIN COOLED
AIRMASS.
FOR THE OVERNIGHT...THE LATEST MESO ETA AND RUC SHOW WK S/W ENERGY
SHIFTING TO A NE-SW AXIS IN LINE WITH MEAN FLOW (NNE) ABV 500 MB.
COMBINED WITH A SMIDGEON OF UVV AND STILL HIGH MEAN RH VLUS EXPECT
SHWRS TO SLOOOWLY WIND DOWN ESP FM SRN HIGHLANDS CO THRU ERN
CHARLOTTE AND LEE CO. WILL WORD THOSE ZONES AS "ENDING AFTER
MIDNIGHT". IN POLK...WILL WORD IT "BY MIDNIGHT". OTRW...JUST LIKE
FRI NIGHT THERE IS PLENTY OF DEBRIS FM OLD HITHER AND YON (YON BEING
THE NW GLF COAST COMPLEX) SO WILL GO CONS CLDS. WILL MAKE FINAL
DETERMINATION BASED ON CONDS JUST PRIOR TO ZONE RELEASE. CURR FCST
TEMPS IN THE LM 70S RIGHT ON.
WILL HAVE TO WATCH PSBL MORNING CONVECTION NEAR THE COAST. FOR
NOW...WITH LOW LVL FLOW VRBL TO S OVERNIGHT WILL KEEP ACTIVITY IN
THE MARINE AREAS ONLY AND LEAVE POST-DAWN SHWR/TSTM PSBLTY FOR THE
MID SHIFT TO DECIDE.
SUNDAY LOOKS TO BE A NEAR REPEAT OF TODAY...WITH MAIN AXIS OF
HEAVIEST RAINS TO BE DETERMINED BY FINAL LOW LVL BDRY LOCATION.
WITH MEAN FLOW EVEN A BIT MORE NELY EXPECT WHATEVER ACTIVITY THAT
DEVELOPS TO CARRY TWD THE COAST.
MARINE: STILL QUIET. CURR BUOY OBS SHOWING WINDS AOB 10 KT AND
SEAS AOB 2 FT.
ZONE UPDATES AVBL BY 10 PM.
GOLDSMITH
FXUS62 KEYW 261944 COR fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
210 AM EDT SUN JUN 26 1999
READERS DIGEST VERSION...THE CURRENT ATL ZFP'S/KMIA SFD LOOK FINE.
NOVEL VERSION...THE SURFACE LOW PRESSURE TROUGH MENTIONED BY THE
PREVIOUS FORECASTER HAS SHIFTED OFFSHORE AND THE PRIMARY AREA OF
PRECIPITATION IS NOW HINGED OVER THE GULFSTREAM. LOOKING AT THE
CURRENT PRECIPITATION PATTERN THE MESO-ETA AND RUC MODELS SEEM TO BE
DOING A FAIR JOB IN HIGHLIGHTING THE MAIN AREAS OF CONVECTION. PATCHY
FOG STILL EXPECTED NEAR DAWN.
MODELS ARE IN GOOD AGREEMENT. A SURFACE RIDGE EXTENDS FROM NEAR
BERMUDA TO THE CENTRAL FLORIDA PENINSULA AND AN EAST-WEST ORIENTED
TROUGH IS LOCATED ACROSS NORTH/SOUTH CAROLINA. GRADIENT BETWEEN THESE
TWO FEATURES IS SETTING UP A MEAN LOW LEVEL SOUTHWEST FLOW ACROSS
THE FORECAST AREA (FA). THE SURFACE TROUGH IS PROGGED TO SHIFT
SLOWLY NORTHWARD TOWARD THE MID-ATLANTIC STATES.
LOOKING AT UPPER LEVEL FEATURES A DIRTY SHORT WAVE RIDGE IS EVIDENT
ACROSS THE SOUTHEAST WITH A SHORT WAVE TROUGH MOVING INTO LOUISIANA.
THE MODELS ARE CONSISTENT WITH THE PLACEMENT OF THESE FEATURES WITH
THE NGM MODEL A BIT MORE AGGRESSIVE INDICATING A MORE ROBUST HIGH
CENTER AT H2 OVER THE FA. MEANWHILE AVN/ETA MAINTAIN A RIDGE AXIS
OVER THE FA. STILL DON'T SEE ANY UPPER LEVEL DIFFLUENCE OR JET
STREAKS DEVELOPING OVER THE FA OVER THE NEXT 48 HOURS SO UPPER LEVEL
FORCING IS NIL.
LOOKS LIKE OUR INSTABILITY IS GOING TO BE LOCALLY GENERATED. PRECIP
WATER (PW) OVER MUCH OF THE FA IS PROGGED TO BE IN THE 2 TO 2.3 INCH
RANGE AND CONSIDERING THE OBSERVED PW WAS 1.97 OFF THE 00 UTC
SOUNDING SEE NO REASON TO DOUBT THE HIGH PRECIP WATER VALUES. NGM
COMPUTED LIFTING INDICES ARE LOW BUT AVN AND ETA ARE IN THE -4 TO
-5 RANGE SATURDAY AFTERNOON. NGM HAS A BIT MORE LOW LEVEL VORTICITY
ON SAT AFTERNOON THAN THE OTHER MODELS. NGM/AVN MOS GUID HAVE BEEN
RUNNING ABOUT 3-4 DEG HIGH ON HIGH TEMPS AND 2-3 DEGREES HIGH ON
LOW TEMPS WILL ADJUST TEMP FORECAST.
IN A NUTSHELL...WE'LL SEE SLIGHTLY ABOVE CLIMO (40 PCNT) CONVECTION
TOMORROW AND SUNDAY AFTERNOON/EVENING. MARINE...CURRENT MARINE
PACKAGE LOOKS GOOD. NO CHANGES RECOMMENDED.
PRELIM
AMG 87/72/88/73 6353
SSI 86/72/87/73 6353
JAX 88/72/91/72 6353
GNV 89/72/91/73 5252 05
SANDRIK
fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1042 AM EST SAT JUN 26 1999
15Z SFC MAP AND LAPS SHOWING THINGS HEATING UP QUITE WELL THIS AM
EVEN THOUGH FAIR AMNT OF MID LVL CLDS AROUND. 15Z TEMPS ALREADY AOA
80 WITH TDS ON THE INCREASE AS WELL. LAPS INDICATING RAPID
DESTABILIZATION UNDERWAY IN AGREEMENT WITH 12Z ETA/RUC RUNS. CONCERN
THIS PM FOR SCT THUNDER TO DVLP ESP IN ASSOCIATION WITH SUBTLE
250MB JET MAX IN IL HEADED THIS WAY. 12Z ETA/RUC BOTH SHOW
INCREASING UPR LVL DVRG WITH THIS FTR AND ATTENDING MOIST FLUX
CONV/THETA ADVT COUPLET OVR N IN BY 00Z. 12HR ETA QPF POINTING TO
CONV PRECIP DVLPMNT THIS PM AND SEEMS REASONABLE GIVEN RADAR TRENDS
BACK SW ACRS C AND S IL. AN THEREFORE INCLINED TO WAFFLE BACK IN
POPS THIS PM ACRS S HALF OF IN ZONES. OTHERWISE PLAN ON TWEAKING
TEMPS TO NR 90 N HALF OF IN CWA AND MI ZONES.
.IWX...NONE
TEH
FXUS73 KIND 260834 in
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
238 PM CDT SAT JUN 26 1999
...GLOBALLY...
SLOW PROGRESSIVE 4 WAVE PATTERN CONTINUES ACROSS THE NORTHERN
HEMISPHERE WITH GLOBAL MOSAIC OF WATER VAPOR IMAGERY FROM GMS-5...
GOES 8/10...AND METEOSAT-7 SHOWING BUILDING HEIGHTS ACROSS THE
PACIFIC OCEAN. THIS WILL RESULT IN SOME AMPLIFICATION OF THE
LONGWAVE PATTERN AND THE GLOBAL MODELS CONFIRM THIS BY THE MIDDLE OF
NEXT WEEK. AMPLIFICATION/PROGRESSION OF THE PATTERN PUSHES THE
CURRENT WEST COAST TROF INTO THE CENTER OF THE CONTINENT FOR MUCH OF
THE COMING WEEK. GOES 10/GMS-5 SHOW A SERIES OF SHORTWAVES WITH
ASSOCIATED JET STREAKS LINED UP ACROSS THE PACIFIC WITH THE LEAD ONE
SLIGHTLY WEAKER THAN THE NEXT TWO. DARKNESS ON WATER VAPOR SUGGESTS
THE LEAD ONE BEING 70-80 KNOTS(CONFIRMED BY AIRCRAFT) APPROACHING
THE PAC NORTHWEST WITH THE ONES SOUTH OF THE ALEUTIANS AND EAST OF
JAPAN ON THE ORDER OF 100 KNOTS OR BETTER. ALL OF THESE SHORTWAVES
PLAY SIGNFICANTLY INTO THE COMING WEEKS WEATHER FOR THE AREA.
THE OVERALL PATTERN COMING THIS WEEK SHOULD EVOLVE INTO A FAIRLY
FLAT RIDGE ON THE EAST COAST...TROF IN THE MID-CONTINENT AREA WITH A
SW/NE RIDGE FROM OFF THE WEST COAST INTO WESTERN CANANDA.
NET RESULT FOR THE IMMEDIATE AREA WILL BE TEMPERATURES AT OR
SLIGHTLY BELOW NORMAL FOR MOST OF THE COMING WEEK WITH AN ACTIVE
WEATHER PATTERN. THE GLOBAL MODELS SUGGEST THAT THIS PATTERN SHOULD
CONTINUE PAST THE FOURTH OF JULY WEEKEND AND INTO PART OF THE FIRST
FULL WEEK OF JULY.
...LOCALLY...
MORNING UPPER AIR/WATER VAPOR SHOWED SEVERAL INTERESTING FEATURES. A
SHORTWAVE WAS MOVING SOUTH INTO WESTERN KANSAS IN THE 850-700 MB
LAYER WHILE A CLOSED LOW WAS MOVING SLOWLY NORTHEAST THROUGH
MISSOURI. SHORTWAVES ASSOCIATED WITH THIS LOW WERE MOVING THROUGH
ARKANSAS AND UP THROUGH MISSOURI/ILLINOIS. 15Z RUC INDICATES THAT
THE RAIN ACROSS ILLINOIS IS ASSOCIATED WITH A TROP FOLD...AND AN
AREA OF LOWER CONDESATION PRESSURE DEFICITS/STEEPER LAPSE RATES THAT
IS PROGGED TO REMAIN MAINLY EAST OF THE FORECAST AREA THROUGH THE
AFTERNOON. AN UNSEASONABLY STRONG SHORTWAVE WAS MOVING ALONG THE
U.S./CANANDIAN BORDER WITH WARM/COLD FRONTS EVIDENT UP TO 850 MB.
18Z SURFACE ANALYSIS HAS COLD FRONT ROUGHLY ALONG A KBJI...KONL...
KLIC LINE WITH A WAVE BETWEEN KLAA AND KGCK. NUMEROUS CONVECTIVE
BOUNDARIES WERE ACROSS THE SOUTHERN HALF OF ILLINOIS. MOISTURE
ANALYSIS HAS MID AND UPPER 60 DEW POINTS ACROSS THE FORECAST AREA
WITH 70 DEW POINTS INTO THE MISSOURI VALLEY.
PROBLEMS THIS PACKAGE ARE MANY...TIMING OF COLD FRONT...MESOSCALE
FACTORS...AND THEN CLOUDS/TEMPS/POPS.
12Z MODELS APPEAR TO HAVE INITIALIZED FAIRLY WELL AND SEEMED TO BE
VERIFYING REASONABLY WELL AT 18Z. THE ETA/RUC DOES PLACE THE COLD
FRONT BETTER THAN THE AVN/NGM BUT THE ETA/RUC ARE COMPLETELY MISSING
THE CURRENT RAIN ACROSS CENTRAL ILLINOIS WHERE THE NGM/AVN ARE
BETTER WITH THE AVN BEING OVERDONE AND TOO FAR NORTH. OVERALL THE
AVN APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK AND STRENGTHENS
THE INCOMING SHORTWAVE TOO MUCH. RECENT PERFORMANCE OF THE ETA IS TO
BE TOO WEAK ON SHORTWAVES AND THIS APPEARS TO BE THE CASE HERE. THUS
THE NGM WILL BE FOLLOWED.
CUTOFF LOW ACROSS MISSOURI WILL CONTINUE TO SLOW DRIFT E/ENE AND
REMAIN WELL AWAY FROM THE FORECAST AREA. RUC/NGM SHOW CONDENSATION
PRESSURE DEFICITS TO REMAIN HIGH SO DRY CONDITIONS TONIGHT LOOK
RIGHT ON WITH A MOSTLY CLEAR/PARTLY CLOUDY SKY. COLD FRONT IN THE
PLAINS SHOULD STALL AT SOME POINT TONIGHT/EARLY SUNDAY AS A WAVE
MOVES UP ALONG IT. QG FORCING AND THERMAL/MOISTURE GRADIENTS SUGGEST
THAT AN MCS SHOULD DEVELOP ACROSS NEBRASKA WHICH WOULD ANCHOR THE
FRONT INITIALLY AND THEN MOVE IT EAST. SUNDAY FRONT SLOWLY
APPROACHES THE AREA AND THUS WILL INTRODUCE POPS FROM WEST TO EAST
USING AFTERNOON/LATE IN THE DAY WORDING.
MAIN PRECIPITATION EVENT TO OCCUR SUNDAY NIGHT/MONDAY AS COLD FRONT
SLOWLY MOVES THROUGH THE FORECAST AREA WITH ADDITIONAL WAVES
TRAVELING ALONG IT. GOOD DRYING/DOWNWARD MOVEMENT BEHIND THE FRONT
INDICATES CLEARING SKIES FROM WEST TO EAST DURING THE DAY MONDAY.
FWC/FAN ARE A GOOD STARTING POINT FOR TONIGHT BUT WILL GO ABOVE
GUIDANCE FOR TONIGHT AND MAKE ADJUSTMENTS ACCORDINGLY FOR LATER
PERIODS.
...EXTENDED...
HIGH PRESSURE TO BUILD INTO THE AREA MONDAY NIGHT/TUESDAY ALLOWING
THE ONLY QUIET PERIOD OF WEATHER. CURRENT SHORTWAVE/JET STREAK SOUTH
OF THE ALEUTIANS TO BE THE FOCUS FOR THE START OF ACTIVE WEATHER FOR
THE WEDNESDAY/THURSDAY TIME PERIOD. WEDNESDAY/THURSDAY TIME PERIOD
COULD GET QUITE INTERESTING AS THIS SHORTWAVE AMPLIFYS. FAIRLY
WIDESPREAD CONVECTIVE RAINS APPEAR LIKELY WITH AMOUNTS BEING
MODERATE TO POSSIBLY HEAVY.
COORDINATED WITH DSM...LSE...CHI...SPI...STL.
.DVN...NONE.
NC
ia
AREA FORECAST DISCUSSION..UPDATED..
NATIONAL WEATHER SERVICE TAUNTON MA
1115 AM EDT SAT JUN 26 1999
NO SIG CHANGES TO THE EARLY AM PKG EXCEPT TO DROP THUNDER FM PVD AND
CAPE COD AND LEAVING SLIGHTEST CHC THUNDER EWB-UUU-WESTERLY WHERE CNV
OCCURS ALONG DRY LINE. DRYING ALOFT PROBABLY OVERWHELMS AND NEGATES
WITH CT UP NR 99F THIS AFTN...THUNDER NOT LIKELY IN OUR CWA.
MAX TEMP THIS AFTN COASTAL PLAIN AND INTERIOR VALLEYS (NON
MARINE-INFLUENCED) 92-95 PER 15Z MWN WB OF 52 AND 12Z ETA FCSTG
29C 1000 MB TEMP THIS AFTN IN HOT WNW SFC FLOW. NO RECORD TEMPS
SINCE RECORDS ARE NR 100F.
SEABRZ NOT FCST (NOT IMPOSSIBLE TO OCCUR) COASTAL E MA THIS AFTN BUT
TURNING OF WINDS TO SSW LIKELY ABOUT 10 MI OUT IN THE WATERS PER
09Z AND 12Z RUC SFC WIND FCSTS. LESS WIND OUTER WATERS THAN ALONG THE
MORE UNSTABLE IMMEDIATE COAST.
WIND OVER THE INTERIOR (BAF/ORE/ORH) SHOULD GUST 22-26 KT FOR A 1-3
HR PRD CENTERED ON 18Z PER DRY UNSTABLE ALY SOUNDING SFC TO 8K.
FLAGGED POTENTIAL OF THIS IN ETA TRANSFER MACRO.
UNCOMFORTABLY HUMID SIGNAL MONDAY AS NGM R1 FLOODS 90-99% RANGE ALL
SNE 12Z MONDAY...SUGGESTING PATCHY DENSE FOG PREDAWN MONDAY ON DECENT
SLY FLOW.
WATER TEMPS THIS AM ON AND NEAR CC NATIONAL SEASHORE
RACE POINT 61F
HERRING COVE 64F
MARCONI 55F
.BOX...NONE.
DRAG
FXUS61 KBOX 261403 ma
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1004 AM EDT SAT JUN 26 1999
NO SIG CHANGES TO THE EARLY AM PKG.
MAX TEMP THIS AFTN COASTAL PLAIN AND INTERIOR VALLEYS (NON
MARINE-INFLUENCED) 89-91F PER 13Z MWN WB OF 49 AND WRKSIG-STAB
PGM.
CONTD SLIGHT CHC OF ISOLATED TSTM 20-23Z ON DRY LINE ROUGHLY
VCNTY EWB-UUU WWD. DRYING ALOFT PROBABLY OVERWHELMS.
SEABRZ NOT FCST (NOT IMPOSSIBLE TO OCCUR) COASTAL E MA THIS AFTN BUT
TURNING OF WINDS TO SSW LIKELY ABOUT 10 MI OUT IN THE WATERS PER
09Z AND 12Z RUC SFC WIND FCSTS. LESS WIND OUTER WATERS THAN ALONG THE
MORE UNSTABLE IMMEDIATE COAST.
WIND OVER THE INTERIOR (BAF/ORE/ORH) SHOULD GUST 22-26 KT FOR A 1-3
HR PRD CENTERED ON 18Z PER DRY UNSTABLE ALY SOUNDING SFC TO 8K.
FLAGGED POTENTIAL OF THIS IN ETA TRANSFER MACRO.
.BOX...NONE.
DRAG
ma
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1000 PM EDT SAT JUN 26 1999
LATEST IR/VAPOR VAPOR IMAGERY SHOWS MID TROPOSPHERIC CIRCULATION IN
NORTHERN ILLINOIS...ALONG WITH AREA OF CONVECTION THAT CONTINUES
NEAR THE SOUTHERN END OF LAKE MICHIGAN. IN ADDITION...SOME SHOWER
ACTIVITY EXTENDS NORTH ALONG THE LAKE MICHIGAN SHORELINE OF
WISCONSIN...AS WELL AS SOME CONVECTION THAT HAS FIRED UP THIS
EVENING IN SOUTHWEST LOWER. FORECAST CONCERN FOR OVERNIGHT HOURS
REVOLVES AROUND PRECIPITATION CHANCES MAINLY FOR THE SOUTHERN TIER
OF COUNTIES.
00Z APX SOUNDING SHOWS STRONG SUBSIDENCE INVERSION IN PLACE AROUND
THE 750 MB LEVEL...ALONG WITH VERY DRY AIR EXTENDING TO AROUND 400
MB. LOW LEVEL MOISTURE STILL REMAINS MARGINAL...ALTHOUGH LAST FEW
HOURS OF OBSERVATIONS ARE BEGINNING TO SHOW INCREASING SURFACE
DEWPOINTS WORKING INTO SOUTHWEST PART OF CWA.
LATEST RUC BRINGS DECENT AREA OF DPVA INTO NORTHWEST LOWER MICHIGAN
BY 09Z. HOWEVER...WITH DRY AIR ALOFT AND WITH MARGINAL LOW LEVEL
MOISTURE AVAILABLE...STILL FEEL THAT SCATTERED POPS ARE A GOOD BET
FOR SOUTHERN TIER OF COUNTIES OVERNIGHT. RUC SHOWS BETTER AVAILABLE
LOW LEVEL MOISTURE ACROSS SOUTHEAST COUNTIES AFTER 09Z...SO WILL
ALSO KEEP SCATTERED POPS IN FOR SOUTHEAST COUNTIES...BUT WILL CHANGE
WORDING TO BRING RAIN CHANCES IN LATE.
TEMPERATURES APPEAR ON TARGET FOR THE MOST PART. WILL ONLY TWEAK IN
A FEW SPOTS TO REFLECT CURRENT TRENDS.
.APX...NONE
ADAM
FXUS63 KMQT 270158 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
700 PM EDT SAT JUN 26 1999
...UPDATE TO PUT CHC OF TSTMS IN REST OF CWA OVERNIGHT/SPEED TIME OF
SHWRS INTO CNTL PART OF CWA BEFORE MIDNIGHT...
LASTEST COMPOSITE RADAR LOOPS/SAT IR AND VIS/LDS DATA SHOWS AN AREA OF
CONSENTRATED SHWERS AND SCT TSMTS JUST AHEAD OF SRN STREAM SHWTWV. MSAS
DATA SHOWS 3000 J/KG JUST SOUTH OF BTL/I-94 AREA. 21Z RUC SHOWS GOOD
AREA OF DPVA ASSOC WITH SHTWV MOVING ENE ACROSS CWA OVERNIGHT AND RADAR
CONTINUITY TAKES THIS LARGE AREA OF PCPN NE ACROSS CWA OVERNIGHT. PWAT
ON MODELS INDICATE 1.5 TO 1.8 INCHES. BOTTOM LINE... IT IS GOING TO
RAIN TONIGHT. SO WILL UPDATE ZONES TO SHOW THAT. RUC SHOWS -2 LINE TO
N OF HTL BY 09Z... SO TSMS POSSIBLE ANYWHERE IN CWA. WILL UPDATE SPS
FOR MENTION OF LOCALLY HEAVY RAIN OVERNIGHT INTO SUNDAY MORNING.
.GRR...NONE.
WDM
FXUS63 KAPX 262013 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1155 AM EDT SAT JUN 26 1999
LATEST WV LOOP SHOWS UPPER LEVEL SHORTWAVE OVER SOUTHERN
SASKATCHEWAN. 500MB RIDGE AXIS LOCATED OVER MICHIGAN WILL CONTINUE
EASTWARD AS SHORTWAVE PULLS NORTHEAST TOWARD LAKE WINNIPEG. 14Z MSAS
SURFACE ANALYSIS SHOWS DIFFUSE LOW PRESSURE NORTH OF MINNESOTA...
WITH A WARM FRONT ARCHING NORTH OF THE U.P. AND A COLD FRONT
EXTENDING SOUTH ACROSS FAR WESTERN MINNESOTA. THIS FRONT WILL REACH
THE FORECAST AREA SUNDAY...BUT THE CONCERN THIS UPDATE IS WITH THE
CONVECTION POTENTIAL DURING THE DAY TODAY.
KDLH 88-D/LDS LOOPS SHOW A LINE OF THUNDERSTORMS OVER NORTH-CENTRAL
MINNESOTA. 12Z RUC INDICATES A WEAK VORTICITY MAX NEAR THUNDER
BAY...WITH A TAIL DRAPING SOUTHWEST INTO NORTHERN MINNESOTA. WHILE
WEAK...THIS FEATURE HAS PROVIDED ENOUGH OF A TRIGGER MECHANISM TO
FIRE THE CONVECTION OVER MINNESOTA.
USING A SIMPLE LINEAR EXTRAPOLATION FROM VISIBLE SATELLITE IMAGES
SHOWING THE CONVECTION OVER MINNESOTA...THIS FEATURE WILL REACH
IRONWOOD BY 20Z. THE RUC ALSO BRINGS THIS FEATURE EAST DURING THE
DAY...WITH A TIMING THAT AGREES WITH THE OBSERVED DATA.
14Z LAMP FOR IWD FORECASTS 90/60 MAX TEMP/DWPT. 12Z GRB SOUNDING
MODIFIED TO REFLECT THESE CONDITIONS YIELDS A CAPE OF 600 J/KG.
THIS IS SIMILAR TO THE 03Z MESOETA...WHICH CALLS FOR UP TO 400 J/KG
BY THIS AFTERNOON. 12Z RUC HAS 925MB LIS IN THE -3 TO -5 RANGE THIS
AFTERNOON.
WITH A FOCUSING MECHANISM APPROACHING THE FORECAST AREA AS THE
ATMOSPHERE DESTABILIZES...WILL CALL FOR A CHANCE OF SHOWERS AND
THUNDERSTORMS LATE THIS AFTERNOON OR THIS EVENING IN THE WESTERN
COUNTIES...AND POSSIBLY INTO THE CENTRAL COUNTIES.
WINDSPEED HAVE PICKED UP AND WILL BE STRONG OUT OF THE
SOUTH/SOUTHWEST...LIGHTEST IN THE EAST AWAY FROM THE APPROACHING
SYSTEM. TEMPERATURE FORECAST LOOKS ON TRACK WITH LATEST SURFACE OBS
AND LAMP GUIDANCE. RECORD HIGH FOR THE 26TH AT MQT IS 87F...WHICH
MAY GO DOWN WITH NO LAKE BREEZE IN THE 20-25 KNOT SOUTHWESTERLY
950MB FLOW.
.MQT...NONE.
JHB
FXUS63 KAPX 261458 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1058 AM EDT SAT JUN 26 1999
GOING FORECAST HAS CURRENT SCENARIO WELL AT HAND. A BRIGHT AND
UNSEASONABLY WARM DAY IS ON TAP FOR FORECAST AREA. HUMIDITY WILL NOT
BE OVERWHELMING TODAY HOWEVER AND PATTERN HAS NOT BEEN STAGNANT LONG
FOR MUCH HAZE. 12Z RUC WOULD CONTINUE SUPPORT FOR A DRY FORECAST
THIS AFTERNOON...AS THE ATMOSPHERE IS QUITE DRY AND THE FLOW IS
STILL ANTICYCLONIC. 12Z MODIFIED APX SOUNDING WOULD GENERALLY
SUPPORT HIGHS IN THE UPPER 80S TO AROUND 90 THIS AFTERNOON. WITH
ONLY MODERATE WAA TAKING PLACE...MOST LOCATIONS CAN EXPECT HIGHS OF
A COUPLE DEGREES WARMER THAN YESTERDAY. 950 MB WINDS AROUND 15 KNOTS
AND LAND/LAKE DELTA T/S AROUND 25 DEGREES SUPPORT LAKE BREEZE
DEVELOPMENT...BUT THEY WILL LIKELY NOT EXTEND TOO FAR INLAND.
FOR UPDATE...HAVE ONLY FRESHENED UP WORDING AND TWEAKED A FEW HIGHS.
.APX...NONE.
BAK
FXUS63 KDTX 261405 mi
FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
320 PM CDT SAT JUN 26 1999
NEARLY HALF OF THE FORECAST AREA IS RECEIVING PRECIPITATION AT THIS
TIME...BUT OVERALL AREAL COVERAGE OF PRECIPITATION IS DIMINISHING IN
WESTERN AREAS. LATEST WATER VAPOR IMAGERY SHOWS CONSIDERABLE DRYING
IN MUCH OF ARKANSAS AND NORTHERN LOUISIANA. THIS DRYING IS
CONSISTENT WITH 18Z RUC WHICH INDICATES A 500 MB TROUGH IS PUSHING
EASTWARD TOWARDS THE MISSISSIPPI BORDER. AS TROUGH PUSHES EASTWARD
ACROSS MISSISSIPPI...PRECIPITATION WILL GRADUALLY DIMINISH FROM WEST
TO EAST ACROSS THE FORECAST AREA THIS AFTERNOON AND TONIGHT. THE AVN
MOS POPS APPEAR TO BE WAY TOO HIGH FOR TONIGHT. I WILL EVEN UNDERCUT
THE NGM MOS POPS FOR TONIGHT TO SHOW WIDELY SCATTERED POPS IN
WESTERN AREAS AND SCATTERED (MOSTLY EARLY EVENING) POPS IN EASTERN
AREAS. FOR SUNDAY...LOWER LEVELS WILL CONTINUE TO HAVE PLENTY OF
MOISTURE. HOWEVER...DUE TO SUBSIDENCE CAUSED BY WEAK MID LEVEL
RIDGING...THE MID LEVEL MOISTURE WILL BE LESS THAN VALUES OF PAST
SEVERAL DAYS. WILL LEAN TOWARDS LOWER NGM MOS POPS...AVN POPS AGAIN
SEEM TOO HIGH. BY MONDAY...POPS SHOULD BE BACK DOWN TO ABOUT 20%
SINCE MID LEVEL MOISTURE WILL BE LIMITED AND NO SIGNIFICANT FOCUSING
MECHANISM WILL BE IN PLACE TO INCREASE PRECIPITATION PROBABILITIES.
FOR TEMPS...EXPECT CONTINUED SIGNIFICANT LOW CLOUD COVERAGE TO KEEP
SUNDAY HIGH TEMPS CLOSER TO AVNS LOWER NUMBERS. OTHERWISE...NGM
NUMBERS LOOK GOOD THROUGH MONDAY.
IN THE EXTENDED FORECAST...MRF MODEL SHOWS COLD FRONT STALLING
ACROSS NORTHERN BORDER OF MISSISSIPPI ON TUESDAY. THEREFORE...EXPECT
INCREASED CHANCE OF PRECIPITATION...ESPECIALLY IN NORTHERN AREAS. BY
WEDNESDAY AFTERNOON...FRONT WILL MOVE NORTHWARD SO ONLY ORDINARY
ISOLATED SUMMER CONVECTION IS ANTICIPATED FOR WEDNESDAY AND
THURSDAY.
QPF DISCUSSION: AIR MASS STILL VERY MOIST AND UNSTABLE THIS
AFTERNOON. MODELS INDICATE MID AND UPPER LEVEL DRYING TO START BY
12Z SUNDAY. APPROACHING VORT MAX TRIGGERING SHOWERS AND
THUNDERSTORMS AT THIS TIME. BELIEVE MOST RAINFALL WILL BE IN THE
FIRST 12 HOURS. WITH ACTIVITY BECOMING MORE SCATTERED IN NATURE ON
SUNDAY. AGREE WITH ETA AMOUNTS THROUGH 24 HOURS...WILL PLACE THE
HIGHEST AMOUNTS ACROSS THE EAST AND SOUTH (1/2 TO 1 INCH) WITH 1/4
TO 1/2 ELSEWHERE.
.JAN...
MS...NONE.
LA...NONE.
AR...NONE.
15
FXUS74 KJAN 260901 ms
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1015 PM CDT SAT JUN 26 1999
THE ZONES HAVE BEEN UPDATED TO REFLECT THE CURRENT MESOSCALE AND
PROJECTED SHORT TERM CONDITIONS. REGIONAL 88D REFLECTIVITY LOOP
SHOWED ORGANIZED CONVECTION WELL TO THE W AND NE OF THE CWFA WITH A
FEW CELLS STRUGGLING TO DEVELOP ALONG THE SLOW-MOVING COLD FRONT IN
FAR NWRN IA. 00Z/27 OAX SOUNDING WAS MODERATELY UNSTABLE /SBCAPES
OF 2800 J/JG/ WITH A MINIMAL AMOUNT OF INHIBITION. THUS IT WOULD
APPEAR THAT ONLY MODEST CONVERGENCE ALONG THE FRONT SHOULD INITIATE
CONVECTION...BUT SO FAR THIS HAS NOT BEEN THE CASE. 00Z/27 RUC
SUGGESTS THAT LOW-LEVEL JET WILL BE THE STRONGEST ACROSS CNTRL NEB
OVERNIGHT WITH MAIN DYNAMIC FORCING /LOW-LEVEL WARM ADVECTION AND
ISENTROPIC LIFT/ SHIFTING NWD INTO THE NRN HALF OF THE STATE THROUGH
12Z. THUS...WE HAVE MAINTAINED THE LIKELY POPS OVERNIGHT ALONG THE
FRONTAL BOUNDARY IN THE N...WHERE LOW-LEVEL CONVERGENCE WILL CONTINUE
TO BE MAXIMIZED. FARTHER S...FORECAST REMAINS MORE UNCERTAIN AS
CONVECTION ACROSS S CNTRL NEB CONTINUES TO WEAKEN. 03Z OBSERVATIONS
SUGGEST A WEAK E-W FRONTAL LINGERING IN THIS AREA...WHICH MAY BECOME
ACTIVE ONCE THE LOW-LEVEL JET INCREASES. E OR SELY STORM MOTION
WOULD MOVE THIS CONVECTION INTO SWRN ZONES...SO WE HAVE MAINTAINED
GOOD CHANCE POPS IN THESE AREAS. 00Z UPPER-AIR DATA SHOWED 1.50
INCH PW AXIS FROM N TX TO SRN NEB...SO HEAVY RAINFALL POTENTIAL IS
THERE. THE MAIN UNCERTAINTY IS IF/WHERE CONVECTION WILL BE
RE-INITIATED.
.OMA...NONE
MEAD
FXUS63 KOAX 261958 ne
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
255 PM CDT SAT JUN 26 1999
...FORECAST CHALLENGES...TIMING AND LOCATION OF TSRA...POTENTIAL FOR
HEAVY RAIN...AND TEMPS
...SYNOPSIS...THE LATEST SFC OBS HAD THE COOL FNT BTWN ONL AND ODX
WITH OFK STILL REPORTING A SW WND AND DWPTS IN THE LWR 70S. SOME
ISOLD -TSRA DEV S OF MARYSVILLE MO...HOWEVER...THESE HAVE
DISSIPATED. AM SNDING SHOWED WRMR MIDLVL TEMPS AND THIS WORKING TO
HINDER DVLPMNT.
...FORECAST...AS THE UPR LVL RDGE BECOMES MORE DEAMPLIFIED...WEATHER
DISTURBANCES FM THE ROCKIES WILL MOVE ACROSS THE NRN AND CNTRL PLNS
VS BEING DIVERTED N INTO CANADA. SFC LO PRES CONTINUES TO WKN OVR
MN WHILE THE MAIN LO OVR WRN KS STRENGTHENS. THE COOL FNT OVR CNTRL
NEB BECOMES MORE ILL DEFINED AS A NEW BOUNDARY OVR SRN NEB/NRN KS
BECOMES THE MAIN FOCUS FOR STORMS. HAVE GENERALLY FOLLOWED THE ETA
THIS PKG. IN THE SHRT TERM...THE ATMOSPHERE CONTINUES TO
DESTABILIZE WITH DAYTIME HEATING AND TEMPS MAINLY FM 85 TO 90. FCST
CAPES ON THE ETA ARND 4000 J/KG WITH LITTLE INHIBITION...BUT A LOOK
OUTSIDE SAYS...THERE IS MORE MIDLVL WRMING THAN IS BEING DEPICTED BY
ALL THE MODELS. THE RUC DID PICK UP ON THE POTENTIAL FOR -TSRA AND
GENERATES SOME PRECIP IN SW IA NW MO BY 18Z...AGAIN LITTLE FOCUS
HERE FOR STORMS THOUGH. THE ETA CONTINUES DVLPMENT THAT IS TAKING
PLACE IN MN AND 88D SHOWING SOME ECHOES FORMING IN KEY PAHA COUNTY
IN NRN NEB. WITH UPR DIV AND FNT...LOCATIONS ALONG THE FNT WILL SEE
THE BEST CHC FOR PRECIP. BY 00Z...THIS WOULD BE NRN AND NE NEB TO
THE NE. AS THE SFC LO STRENGTHENS...THE BETTER MOISTURE
CONVERGENCE...IS IN SW NEB...AND GRADUALLY SAGS TO KS. WITH THE
ABOVE FEATURES IN MIND WILL WEIGHT POPS HIGHEST NR FNT AND IN SW CWA
AND LEAST IN FAR E TON. AS A STG DISTURBANCE MOVES ACROSS THE STATE
SUN...PRECIP SHOULD HAVE GREATER COVERAGE.
SOME CONCERN WITH HEAVY RAIN AS H85 DEWPOINTS FM 16 TO 19 DEG C OVR
CNTRL NEB. THE FCST SNDINGS HAV PRECIP WATER IN EXCESS OF 1.6
INCHES TON THRU SUN. DESPITE STGR MID AND UPR LVL FLO...STM
MOVEMENT ONLY 5 TO 15 KT. LOOK AT CORFIDI VECTORS POINTS TO E OR NE
MOVEMENT WITH DEV S ALONG THE FNT.
GUID TEMPS TOO COOL FOR OFK SUN AND WITH A LOT OF CLDS OMA/LNK
SHOULD BE AOB GUID. AS THE N WNDS PICK UP SUN EVE...COOLER TEMPS
FOR MON AM. FOR MON...AVN HAS A WAVE MOVE ACRS THE NRN PLNS AND THE
MRF TAKES IT FARTHER S...AT THIS TIME WILL LEAVE MON DRY.
EXTENDED HAS DRY WX FOR TUE AND CHC FOR TSRA WED AND THU.
.OMA...NONE
ZAPOTOCNY
FXUS63 KGID 261916 ne
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
1000 AM EDT SAT JUN 26 1999
FCST IN GOOD SHAPE WITH ONLY MINOR TWEEKS TO REMOVE THE ERLY AM FOG
THAT HAS BURNED AWAY. BUF/ALY 12Z RAOBS NEED A HEALTHY SFC
MODIFICATION INTO THE UPR 80S FOR A LONGSHOT AT ANY CONVECTIVE
DEVELOPMENT TAFTN. SUBS INVERSION AND DRY AIR ABV 800 MB ASSOC WITH
DVLPG MIDLVL RIDGING MAINTAINS A SMALL CAP AND SHUD MIX DOWN A BIT TO
HELP LESSEN LLVL INSTAB. ALSO NO TRIGGER EXPECTED AS SFC BNDRY THAT
PASSED THRU YDY SITS ACRS CNTRL PA AND NEG H8 THETA-E ADVECTION
ONGOING ACRS CNY. PIT RAOB THE ONLY OF OUR NEIGHBORS TO BECOME
UNSTABLE TDY. 09Z RUC AND 03Z ETA KEY IN ON THIS WITH FCST LI'S OF
ZERO TO -2 VCNTY OF THE BNDRY ACRS CNTRL PA...SO WY VALLEY THE
ONLY PLACE IN CWFA THAT HAS A MINIMAL THREAT FOR ISOLD TSRA TO BREAK
THRU THE CAPPING INV. FCST DRY ATTM AND BLV CHCS NOT GREAT ENUF TO
CHANGE THIS. IF IT OCCURS WL GO NOWCAST ROUTE.
TEMPS UPR 80S-NR 90 SUPPORTED BY THE FULL SUN AND LOCALIZED EFFECTS.
.BGM...NONE.
BREWSTER
FXUS61 KBUF 261350 ny
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
915 PM EDT SAT JUN 26 1999
ONLY ACTIVITY CURRENTLY NOTED OVER ILM FCST AREA ARE DYING RW ALONG
SEABREEZE IN NERN SC. BUT LINE OF DECAYING RW/TRW JUST SW OF AREA
MOVING TOWARD WILLIAMSBURG/GEORGETOWN COUNTIES. WILL DECIDE ON POPS
FOR THIS AREA AT PRESS TIME. ELSEWHERE... 00Z CSTL RAOBS SHOWED
DECENT MOISTURE AND GOOD INSTABILITY/CAPE W/ BEST PARAMETERS AT CHS.
21Z RUC2 SHOWED WEAK VORTICITY MAXIMA ALF LINGERING NEAR THE AREA
OVRNGT & GENERAL SFC TROFINESS TO PERSIST SO WILL MAINTAIN A SMALL
CHC OF PRECIP. FOG STABILITY INDICES DON/T SHOW MUCH HOPE FOR DENSE
FOG DESPITE HIGH DEWPTS. TEMPS LOOK FINE BASED ON CURRENT DEWPTS &
LAMP GUIDANCE.
CWF: CSTL WINDS AVERAGING SW 10 KT. SEAS ARND 3 FT AT FPSN7/41004.
SFC FEATURES AREN/T PROGGED TO CHANGE MUCH OVRNGT SO NO BIG CHANGES
PLANNED TO FCST.
.ILM...NONE.
LGE
FXUS72 KRAH 270108 nc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
950 AM EDT SAT JUN 26 1999
IR/VIS SAT LOOPS SHWG CI CONTG TO SPRD NEWD ACRS FA THIS MRNG WITH
PCPN STILL BACK ACRS WRN KY/SRN IL. 13Z SFC ANLYS INDICTG SFC TROF
FM CNTL MO THRU SRN IL TO ERN KY WITH 70 DGR DWPTS UP INTO CNTL IND
AND XTRM SW OH. TROF XPCTD TO CONT SLOW NWRD PUSH THRU THE DAY TDA
WITH MSTR INCRSG FM THE SW. 09Z RUC HOLDING BACK ON BRINGING DPR
MSTR IN THRU THIS AFTN SO XPCT ANY WIDESPRD PCPN TO HOLD OFF TIL
TNGT. HOWEVER...MODIFIED ILN 12Z RAOB FOR HIGHS NEAR 90/DWPTS NEAR
70 YIELDING CAPE OF ARND 2000 J/KG AND LI OF -4. WITH WK LLVL CONV
ALG BNDRY THRU THIS AFTN...SOME TSTMS MAY STILL POP UP AND WL CONT
LOW CHC POPS ACRS SRN PORTION OF FA.
THINK CI WL CONT TO BE THIN ENUF TO WARRANT MSTLY SUNNY FOR MOST OF
FA. HI CLDS SHUD HELP KP TMPS DOWN SOMEWHAT. CENTER ENERGY BLOCK
METHOD OFF MRNG SNDG GIVING 91.6 FOR HIGH TDA AT ILN WITH 90.7 WHEN
ACCOUNTING FOR CI. 1000-850 MB THCKNSS ALSO PROGD TO BE QUITE A BIT
HIGHER THAN YESTERDAY BY LATE THIS AFTN...ESPLCY ACRS ERN PORTIONS
OF FA. THUS...PLAN ON BUMPING TMPS UP A LTL ACRS ENTIRE FA WITH NEAR
90 ACRS THE W AND LOW 90S IN THE E.
.ILN...NONE.
LOTT
oh
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
945 PM EDT SAT JUN 26 1999
KGSP RADAR SHOWS TSRA CONTINUING ACROSS THE NC FOOTHILLS/PIEDMONT...
BUT ONLY DISSIPATING LITE RAIN ACROSS THE MOUNTAINS AND UPSTATE SC. FOR
THE SHORT TERM...EXPECT MOST OF THE DEEP CONVECTION TO CONTINUE N OF AN
AVL/CLT LINE AS IT DEVELOPS NORTHWARD INTO AN UNUSED AIR MASS ACROSS
THE NW PIEDMONT OF NC. THIS PARTICULAR CONVECTION SHOULD DIMINISH
TOWARD MIDNITE. WOULD LIKE TO UPDATE ZONES TO LOWER SOME OF THE PRECIP
CHANCES...BUT AM NOT SURE THAT WOULD BE THE BEST COURSE OF ACTION FOR
THE ENTIRE FCST AREA. ALTHOUGH MAIN FORCING FROM VORT CENTER SEEN IN
WATER VAPOR IMAGERY MOVING OVER WRN TN/NWRN MS SHOULD REMAIN TO OUR W
OVERNITE...LATEST RUC SHOWS LOW LEVEL FORCING MOVING ACROSS CENTRAL GA
AND TOWARD THE UPSTATE EARLY SUNDAY. IN RESPONSE...THE RUC SHOWS AN
AREA OF PRECIP MOVING BACK IN TOWARD NE GA/UPSTATE SC BY 09Z. FOR THAT
REASON...WILL NOT SIGNIFICANTLY LOWER PRECIP CHANCES.
.GSP...NONE.
MOORE
FXUS62 KCHS 270109 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
850 PM EDT SAT JUN 26 1999
21Z RUCII RUN SHOWS VORT LOBE OVER SOUTH CAROLINA MOVING EAST BY 03Z.
BOTH WV STLT LOOP AND CAE 88D INDICATE DEVELOPMENT ON THIS FEATURE TO
THE EAST. RUCII LIS SHOW THAT MOST UNSTABLE AIR IS BETWEEN OGB AND CHS.
THIS IS WHERE THE LTG DATA INDICATES THE MOST THUNDERSTORM ACTIVITY IS
LOCATED. MOST ENERGY IS NOW IN THE FLORIDA PANHANDLE. PLAN ON CUTTING
POPS CONSIDERABLY DOWN TO ABOUT 30% WITH MAINLY SHOWERS BUT WILL MENTION
A THUNDERSTORM IS POSSIBLE. WITH HIGH DEWPOINTS...LOWS IN THE LOWER 70S
STILL OK.
WRKZFP IN 5-10 MINUTES.
.CAE...NONE.
TTH
FXUS62 KCHS 261841 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1017 AM EDT SAT JUN 26 1999
EARLY VIS IMAGES REVEAL ABUNDANCE OF LOW CLOUDS ACROSS CWFA...BUT
SOME BREAKS ALREADY SHOWING UP IN NORTHEAST GEORGIA...WESTERN-MOST
SOUTH CAROLINA AND PARTS OF SOUTEHRN NORTH CAROLINA MOUNTAINS.
SURFACE OBSERVATIONS SHOW NEARLY UNIFORM TEMPERATURES FROM ALL BUT
HIGHEST MOUNTAIN LOCATIONS AND FOG TRNASFORMING TO HAZE WITH
CONTINUED VISIBILITIES BELOW 4 MILES MANY SPOTS.
SURFACE AND UPPER AIR PATTERN ARE A BIT COMPLICATED. ELONGATED
SURFACE TROF OVER CWFA AND MOST OF SOUTHEAST STATES...UPPER LOW
DIFFICULT TO ANALYZE BUT OVERALL TROF PATTERN IS DISPLAYED. WEAK
UPSLOPE FLOW INTO MOUNTAINS THIS AFTERNOON SHOULD RESULT IN
WIDESPREAD RW COVERAGE ALONG EASTWARD FACING SLOPES; LATEST RUC
KEEPS LOW LVL RH IN 80-90 PERCENT RANGE THROUGH THE DAY. CAPES ON
MODIFIED SOUNDINGS HIGH AGAIN TODAY WITH TEMPERATURES IN THE LOWER
80S BUT MID LVL TEMPS REMAIN QUITE HIGH. PRECIPITABLE WATERS STILL
IN THE 1.8 TO 1.9 INCH RANGE SO HEAVY PRECIPITATION COULD FALL IN
MANY LOCATIONS THIS AFTERNOON.
TEMPERATURE FORECAST TRICKY THIS AFTERNOON AND HIGHLY DEPENDENT
ON WHO GETS BRIEF BURSTS OF SUNSHINE. CURNT ZONES HAVE RANGE OF
TEMPERATURES...WHICH STILL LOOK GUD. MAY SPLIT OFF SOUTWHEST MOST
COUNTIES SINCE SATELLITE WOULD SUGGST BREAKS IN OVC IMMINENT THERE
AND GIVEN THAT GREENWOOD REACHED 89 ON FRIDAY.
.GSP...NONE.
BURRUS
FXUS62 KCAE 261401 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
946 AM EDT SAT JUN 26 1999
DISC: 13Z ANALYSIS SHOWS WK BNDRY NW TO SE ACRS THE NRN PTN OF SC.
SATELLITE SHOWS LOTS OF CLOUDS ACRS THE STATE THIS MORNING. A FEW BRKS
JUST W OF THE SAVANNAH RIVER...BUT CLDS BEGINNING TO FILL IN EVEN THERE.
12Z RUC INDICATING SFC FRNTL BNDRY NOT EXPECTED TO MOVE TO MUCH THRU THE
DAY REMAINING ACRS THE NRN PTN OF THE STATE. AT H5...S/W MOVS VERY
LITTLE THRU THE AFT ACRS THE ERN PTN OF THE STATE. WITH MODELS SHOWING
QUITE A BIT OF MOISTURE OVR THE AREA...MAY SEE A FEW BREAKS IN THE CLDS
DURING THE AFT...BUT MSTLY CLDY WILL STILL DO FINE. WL KEEP HIGHER POPS
WHERE BEST MOISTURE CONVERGENCE EXPECTED...WHICH IS ACRS NRN AND ERN SC
NEAR THE BNDRY...LESS ALNG THE SAVANNAH RIVER AREA. AS FAR AS TEMPS
GO...WL CONT TO MONITOR THRU ISSUANCE TIME...BUT MID 80S MAY BE OK FOR
MOST AREAS.
.CAE...NONE.
LCV
FXUS62 KCHS 261332 sc
AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
838 PM CDT SAT JUN 26 1999
LATEST RUC MDL SHOWING A S/W MOVING IN AND AFFECTING THE WESTERN PART
OF THE CWA LATER TONIGHT. SATELLITE ALREADY SHOWING THE AFFECTS OF THIS
S/W OVER WY AND INTO W SD...WHERE THERE IS WIDESPREAD MID LEVEL CLOUDS
AND SOME SHRAS/TSRAS. BASED ON THE SATELLITE AND RUC...WILL PUT IN A
CHANCE OF SHRAS ACROSS C AND NC SD FOR LATER TONIGHT AND GO WITH MOSTLY
CLOUDY. DUE TO CLOUD COVER ACROSS THE C AND NC...WILL UP THE LOW TEMP
FORECAST A LITTLE. WILL ALSO MAKE SOME CHANGES TO NE SD AND WC MN
FORECASTS.
.ABR...NONE
MOHR
FXUS63 KABR 262005 COR sd
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
248 PM CDT SAT JUN 26 1999
CDFNT IS MOVING THRU HEART OF CWA ATTM...WITH PREFRONTAL WIND SHIFT
INTO SW MN AND NW IA. SRN END OF FNT ACRS NERN NEBRASKA HAS REALLY
SLOWED TO A CRAWL...SIGNALING A REFOCUS TO AREA OF CONCERN TOWARD S
AND E. ON WV/IR...SUBTLE JET IMPULSE LOOKS TO BE SLIPPING INTO ND
ATTM WITH SOME LIFT INDICATED GLANCING THRU WRN SD...PERHAPS HELPING
TO INITIATE NCTNRL NEBRASKA CONVECTION IN REGION OF SLIGHTLY DRIER
MID LVL AIR. OTHERWISE...GUIDANCEWISE... MAIN DIFFERENCE SEEMS TO BE
IN THE SWRD PUSH OF LO LVL BNDRY. OVERALL..AVN IS A MELD OF TYPICAL
NGM AND ETA POSITIONS...AND SEEMS TO HAVE GUD HANDLE ON PROGGED UPPR
DVRG FLDS AT 6H...ESPLY UPSTREAM IN INTERMOUNTAIN W. ETA NOT TOO
BAD AS WELL...AND ACTUALLY PREFER FLATTER RIDGE OVR NRN PLAINS FOR
MOST PART.
SHORT TERM CONCERN IS CONVECTIVE DEVELOPMENT. STLT SOUNDER AND LAPS
ARE CLOSE IN SHOWING GREATEST INSTABILITY ACRS ERN 1/2 OF CWA...
WHERE CAPES ARE 1500-2000 J/KG...AND INHIBITION HAS DECREASED TO
10 TO 30 J/KG...WITH ATTAINABLE LFC BLO 700 HPA. MUCH OF CWA LIES
BTWN BEST PCPN FORCING. WOULD BELIEVE THAT LARGE PART OF FORCING
FOR PCPN TNGT IS MOSTLY RELIANT ON LOW LEVEL FEATURES...WHICH WOULD
SUGGEST THAT ACTIVITY WILL BE MAINLY LT AFTN AND EVNG...BUT WL HAVE
TRAILING EDGE OF RRQ FOR BIT OF BOOST THIS EVNG. LTST RUC INDICATES
THAT DEGREE OF LOW LVL MSTR CONVERGENCE SHOULD INCREASE 21Z-00Z ALG
BNDRY AS IT EXITS SD CWA...BUT DOES NOT ADEQUATELY CAPTURE THE
PREFRONTAL WIND SHIFT. WHILE WIND FIELDS ARE NOT FAVORABLE ON
LARGER SCALE FOR SIG ORGANIZATION OF STMS...LCL ENHANCEMENTS ALG
PREFRONTAL SHIFT MAY BE ENOUGH TO PUSH A FEW DEVELOPING STORMS OVR
SVR THRESHHOLD THIS EVNG ACRS SW MN AND NW IA...ESPLY ENCOURAGING
IS THE PROFILER AT WDL. MARGINAL SVR HAIL...AND DAMAGING WINDS
WOULD BE LARGEST THREAT...WITH ADDED POTENTIAL FOR TRAINING RAINFALL
ACRS SRNMOST CWA. FFG HAS RECOVERED IN THESE AREAS...EXCEPT FAR
NE NEBRASKA...BUT WITH ENHANCEMENT OF VEGETATION NOW...WOULD THINK
IT MAY BE ON LOW SIDE ANYWAY.
DIFFICULTY FROM THEN OUT HAS TO DO WITH EFFECT OF WK RIPPLES IN
ZNL FLOW. SOME AGREEMENT BTWN MDLS THAT A DEEPER SYNOPTIC SCALE
FORCING WITH INTERMOUNTAIN W WAVE BEGINS TO AFFECT CWA LT TNGT
W...AND THEN THROUGH MOST OF CWA ON SUN. LIKE OVERALL ETA POSITIONING
OF POTENTIAL MCS DEVELOPMENT...WHICH WOULD BRING HIGHEST POPS ACRS
SRN CWA SUN. COOLER AND POTENTIALLY COOLER AIR WILL MEAN A CHILLIER DAY
FOR CWA...ESPLY WITH RAINFALL...BUT FWC TMPS SEEM TOO COOL. TRAILING
IMPULSE LEAVES SUN NGT WITH LINGERING SHRA E. SOME HINT THAT LLM
WILL BE SLOW TO LEAVE SRN CWA.
ON MONDAY...RESIDUE OF MCS COULD BRUSH SRN CWA...AND WL CARRY ONLY
SMALL POP TO COVER...WHILE DEEPER DRY AIR PROTECTS NORTHERN AREAS.
TMPS TO SHOW A MODEST RECOVERY AS WELL.
EXTENDED RANGE POSES OWN SET OF PROBLEMS AS FLOW TRANSISTION TO
NRN PLAINS DEEP TROUGH CONTINUES...WHICH AT LEAST MDLS ALL SUPPORT.
TUE LUKS TO BE DRIEST TIME...WITH EXCEPTION BEING BY EVNG IN WRN CWA.
DRY AIRMASS AND WK FLOW FOR COOL START TUE...THEN SHUD HEAT OUT
MODERATELY WELL. SFC BNDRY PUSHES THRU CWA SLOWLY WED AS JET
IMPULSE ROUNDS DEEPENING TROUGH...THEN CYCLONIC COLD CORE DOMINATES
ON THU. BEST MSTR FCST TO WRAP THRU NRN CWA...BUT AT THIS RANGE WL
MNTN SHOWERS ALL AREAS AS STEEP MID LVL LAPSE RATES COINCIDE. WL
PROBABLY THROW IN MNTN OF TSRA AS WELL. TMPS TO REMAIN WELL ON
COOL SIDE OF NORMAL...NO SIG WARMUPS SUGGESTED THRU 4TH.
.FSD...NONE
CHAPMAN
FXUS63 KUNR 261538 sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
955 AM EDT SAT JUN 26 1999
PLENTY OF CLOUDS STREAMING OVER CWA IN ADVANCE OF H5 TROUGH...WITH
SURFACE DEWPOINTS MOSTLY IN THE LOWER 70S. DEPTH OF MOISTURE IS
WELL REPRESENTED FROM 12Z BNA SOUNDING (A PWAT VALUE OVER 2
INCHES).
FROM KMRX AND KHTX 88D/S AS WELL AS THE LATEST RUC AND MESO-
ETA...SHOWERS AND THUNDERSTORMS BECOMING LIKELY THIS AFTERNOON
ACROSS MOST OF EAST TENNESSEE AND EXTREME SOUTHWEST NORTH CAROLINA.
SO WILL CHANGE ZONES TO REFLECT THIS TREND...OTHER THAN FOR AN
UPSLOPE INDUCED SHOWER OVER BLOUNT COUNTY TENNESSEE.
WOULD TEND TO DISCOUNT THE HEAVY RAIN POTENTIAL IN THE ZONES AS PER
THE 09Z RUC AND 03Z MESOETA...BUT WILL LEAVE IN CONSIDERING THE
"LOCAL" TERMINOLOGY. TEMPERATURES ARE ON TRACK AND LOOK GOOD FOR THIS
AFTERNOON.
DM
tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
243 PM CDT SAT JUN 26 1999
RATHER HIGH SURFACE DEWPOINTS...SHOWING SUMMER IS DEFINITELY HERE WAS
NOTED OVER THE COUNTY WARNING AREA EARLY THIS AFTERNOON. EXCEPT FOR
THE MTNS...HAD DEWPOINTS IN THE 60S...WITH LATE MORNING 70 READINGS
FROM INK TO CNM. AT THE SURFACE...A TROF WAS NOTED EXTENDING FROM
BETWEEN CAO/DHT...TO WEST OF ROW...TO AROUND GDP. EARLIER...OUR 12Z
RAOB INDICATED 7H TEMPS AT +15C...BUT 5H TEMPS HAD COOLED TO
-10C...MAKING FOR STEEP MID-LEVEL LAPSE RATES. THIS WAS CAUSING AN
AREA OF AC/ACC CLOUDS JUST NW OF HERE EARLIER. THE STRONG CAPPING
APPEARS TO BE HOLDING STRONG FOR THE PERMIAN BASIN...BUT TERRAIN
EFFECTS WAS CAUSING STORMS TO FIRE IN THE SACRAMENTO...GUADALUPE...
AND DAVIS MTNS.
THROUGH THE EVENING...MID-LEVEL CAPPING SHOULD HOLD FOR THE LOWLANDS
THUS DRY CONDITIONS WILL CONTINUE. THE 18Z RUC...ALONG WITH THE 12Z
MODELS SHOW 7H TEMPS SHOULD REMAIN AT LEAST 15C...WITH 5H TEMPS
WARMING TO THE -6 TO -7 RANGE. WILL NOTE ISOLATED TO WDLY SCATTERED
CONVECTION IN THOSE FAVORED PLACES. WITH NOT MUCH CHANGE EXPECTED...
WILL GO FOR A SIMILAR FORECAST TOMORROW AND MONDAY. GOING ALONG WITH
OUR MORNING UPDATE...WILL ADD MENTION OF MORNING LOW CLOUDS FOR MOST
OF THE PERMIAN BASIN. GULF MOISTURE MADE FURTHER NW PROGRESS THAN 1ST
THOUGHT YSTRDY...AND A SIMILAR SOLUTION SUGGESTED IS TMRW MORNING.
FOR THE EXTENDED...MEAN TROFFING AND THE NORTHERLY JET MAX WILL DROP
FURTHER SOUTH. THUS WILL INTRODUCE ISOLATED TO WDLY SCATTERED POPS
MAINLY FOR THE NORTHERN PERMIAN BASIN TUESDAY...AND KEEP THE REST OF
THE FLATLAND AREAS DRY. FROM OROGRAPHIC EFFECTS...WILL KEEP A CHANCE
OF CONVECTION IN THE MTNS.
WILL GO ABOVE MODEL TEMPS...ESPECIALLY THE TOO COOL NGM. WORK ZONES
FOR THIS EVENING ARE ON THE WAY. 1ST GUESS NUMBERS BELOW.
MAF 71/101/70/103 -/0/-/0
CNM 70/103/71/104 1/-/1/-
MRF 61/94/61/94 1/-/1/-
P07 73/96/74/97 -/0/-/0
RSB
FXUS74 KEWX 261934 tx
SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
930 AM CDT SAT JUN 26 1999
AXIS OF TAIL DRAGGING TROF REMAINS ALONG COASTAL PLAINS AND RUC
PROGS KEEP IT THERE THROUGH THE DAY. REMNANTS OF NORTH TEXAS MCS
PUSHING SOUTHWARD MAY PROVIDE FOCUS FOR DEVELOPMENT IN UNSTABLE AIR
MASS OVER SOUTHERN ZONES. EXPECT SOME DESTABILIZATION OVER NORTHERN
AND WESTERN ZONES WITH HEATING UNDERWAY. CURRENT 20 PERCENT POPS
WILL STAND FOR NOW WITH CLOSE WATCH ON AREAS OF DEVELOPMENT.
.SAT...FLASH FLOOD WATCH EXTREME SOUTHEAST TEXAS TODAY
10/01
FXUS64 KHGX 261440 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
319 AM EST SUN JUN 27 1999
MODEL DIVERGE WITH DIFFICULT FCST AGAIN. NGM TOO STRONG WITH PLAINS
SYS DY2 AND ETA NOT KEYING IN ON SUBTLTIES. LTST RUC AND WV
IMAGERY SHOW PLUME OF HI PWAT AIR RIDGED ACRS FA. WK WAVE FM NW
FA PER KLOT VWP TO SWRN IN. SWRN IN WAVE TO MOVE NE AND KEEP ERN ZNS
IN OCNL SHRA/TSRA TODAY. WRN ZNS WL LIKELY SEE A BREAK FM CURRENT
CONV BUT UNABLE TO RULE OUT LT AFTN TSRA WITH BNDRYS SET UP AND
CDFNT ACRS NWRN IA ATTM NEARING. HI THETA-E AIR/PWAT REMAIN THROUGH
FCST PD AND HARD TO RULE OUT/TIME PCPN. BETTER CHC TSRA DY2 WITH
FRONT APPROACHING HI CHC POPS. IGNORING NGM SVR WX POTNL ATTM.
PRIMARY THREAT COULD BECOME URB/SML STREAM FLODDING WITH HI PCPN
RATE/DURATION WITH POOR MODEL SOLN UNABLE TO KEY ON HIGHEST FUTURE
THREAT AREA...BUT WRN FA AND MI COS THAT HAVE ALREADY SEEN STM TOTALS
1-2.5 GOOD BET.
SBN WT 086/068 086/065 078 15545
FWA WT 086/068 086/066 080 15545
AOH WT 086/068 087/067 080 15545
.IWX...NONE
MURPHY
FXUS73 KIND 270809 in
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1042 AM EST SAT JUN 26 1999
15Z SFC MAP AND LAPS SHOWING THINGS HEATING UP QUITE WELL THIS AM
EVEN THOUGH FAIR AMNT OF MID LVL CLDS AROUND. 15Z TEMPS ALREADY AOA
80 WITH TDS ON THE INCREASE AS WELL. LAPS INDICATING RAPID
DESTABILIZATION UNDERWAY IN AGREEMENT WITH 12Z ETA/RUC RUNS. CONCERN
THIS PM FOR SCT THUNDER TO DVLP ESP IN ASSOCIATION WITH SUBTLE
250MB JET MAX IN IL HEADED THIS WAY. 12Z ETA/RUC BOTH SHOW
INCREASING UPR LVL DVRG WITH THIS FTR AND ATTENDING MOIST FLUX
CONV/THETA ADVT COUPLET OVR N IN BY 00Z. 12HR ETA QPF POINTING TO
CONV PRECIP DVLPMNT THIS PM AND SEEMS REASONABLE GIVEN RADAR TRENDS
BACK SW ACRS C AND S IL. AN THEREFORE INCLINED TO WAFFLE BACK IN
POPS THIS PM ACRS S HALF OF IN ZONES. OTHERWISE PLAN ON TWEAKING
TEMPS TO NR 90 N HALF OF IN CWA AND MI ZONES.
.IWX...NONE
TEH
in
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
238 PM CDT SAT JUN 26 1999
...GLOBALLY...
SLOW PROGRESSIVE 4 WAVE PATTERN CONTINUES ACROSS THE NORTHERN
HEMISPHERE WITH GLOBAL MOSAIC OF WATER VAPOR IMAGERY FROM GMS-5...
GOES 8/10...AND METEOSAT-7 SHOWING BUILDING HEIGHTS ACROSS THE
PACIFIC OCEAN. THIS WILL RESULT IN SOME AMPLIFICATION OF THE
LONGWAVE PATTERN AND THE GLOBAL MODELS CONFIRM THIS BY THE MIDDLE OF
NEXT WEEK. AMPLIFICATION/PROGRESSION OF THE PATTERN PUSHES THE
CURRENT WEST COAST TROF INTO THE CENTER OF THE CONTINENT FOR MUCH OF
THE COMING WEEK. GOES 10/GMS-5 SHOW A SERIES OF SHORTWAVES WITH
ASSOCIATED JET STREAKS LINED UP ACROSS THE PACIFIC WITH THE LEAD ONE
SLIGHTLY WEAKER THAN THE NEXT TWO. DARKNESS ON WATER VAPOR SUGGESTS
THE LEAD ONE BEING 70-80 KNOTS(CONFIRMED BY AIRCRAFT) APPROACHING
THE PAC NORTHWEST WITH THE ONES SOUTH OF THE ALEUTIANS AND EAST OF
JAPAN ON THE ORDER OF 100 KNOTS OR BETTER. ALL OF THESE SHORTWAVES
PLAY SIGNFICANTLY INTO THE COMING WEEKS WEATHER FOR THE AREA.
THE OVERALL PATTERN COMING THIS WEEK SHOULD EVOLVE INTO A FAIRLY
FLAT RIDGE ON THE EAST COAST...TROF IN THE MID-CONTINENT AREA WITH A
SW/NE RIDGE FROM OFF THE WEST COAST INTO WESTERN CANANDA.
NET RESULT FOR THE IMMEDIATE AREA WILL BE TEMPERATURES AT OR
SLIGHTLY BELOW NORMAL FOR MOST OF THE COMING WEEK WITH AN ACTIVE
WEATHER PATTERN. THE GLOBAL MODELS SUGGEST THAT THIS PATTERN SHOULD
CONTINUE PAST THE FOURTH OF JULY WEEKEND AND INTO PART OF THE FIRST
FULL WEEK OF JULY.
...LOCALLY...
MORNING UPPER AIR/WATER VAPOR SHOWED SEVERAL INTERESTING FEATURES. A
SHORTWAVE WAS MOVING SOUTH INTO WESTERN KANSAS IN THE 850-700 MB
LAYER WHILE A CLOSED LOW WAS MOVING SLOWLY NORTHEAST THROUGH
MISSOURI. SHORTWAVES ASSOCIATED WITH THIS LOW WERE MOVING THROUGH
ARKANSAS AND UP THROUGH MISSOURI/ILLINOIS. 15Z RUC INDICATES THAT
THE RAIN ACROSS ILLINOIS IS ASSOCIATED WITH A TROP FOLD...AND AN
AREA OF LOWER CONDESATION PRESSURE DEFICITS/STEEPER LAPSE RATES THAT
IS PROGGED TO REMAIN MAINLY EAST OF THE FORECAST AREA THROUGH THE
AFTERNOON. AN UNSEASONABLY STRONG SHORTWAVE WAS MOVING ALONG THE
U.S./CANANDIAN BORDER WITH WARM/COLD FRONTS EVIDENT UP TO 850 MB.
18Z SURFACE ANALYSIS HAS COLD FRONT ROUGHLY ALONG A KBJI...KONL...
KLIC LINE WITH A WAVE BETWEEN KLAA AND KGCK. NUMEROUS CONVECTIVE
BOUNDARIES WERE ACROSS THE SOUTHERN HALF OF ILLINOIS. MOISTURE
ANALYSIS HAS MID AND UPPER 60 DEW POINTS ACROSS THE FORECAST AREA
WITH 70 DEW POINTS INTO THE MISSOURI VALLEY.
PROBLEMS THIS PACKAGE ARE MANY...TIMING OF COLD FRONT...MESOSCALE
FACTORS...AND THEN CLOUDS/TEMPS/POPS.
12Z MODELS APPEAR TO HAVE INITIALIZED FAIRLY WELL AND SEEMED TO BE
VERIFYING REASONABLY WELL AT 18Z. THE ETA/RUC DOES PLACE THE COLD
FRONT BETTER THAN THE AVN/NGM BUT THE ETA/RUC ARE COMPLETELY MISSING
THE CURRENT RAIN ACROSS CENTRAL ILLINOIS WHERE THE NGM/AVN ARE
BETTER WITH THE AVN BEING OVERDONE AND TOO FAR NORTH. OVERALL THE
AVN APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK AND STRENGTHENS
THE INCOMING SHORTWAVE TOO MUCH. RECENT PERFORMANCE OF THE ETA IS TO
BE TOO WEAK ON SHORTWAVES AND THIS APPEARS TO BE THE CASE HERE. THUS
THE NGM WILL BE FOLLOWED.
CUTOFF LOW ACROSS MISSOURI WILL CONTINUE TO SLOW DRIFT E/ENE AND
REMAIN WELL AWAY FROM THE FORECAST AREA. RUC/NGM SHOW CONDENSATION
PRESSURE DEFICITS TO REMAIN HIGH SO DRY CONDITIONS TONIGHT LOOK
RIGHT ON WITH A MOSTLY CLEAR/PARTLY CLOUDY SKY. COLD FRONT IN THE
PLAINS SHOULD STALL AT SOME POINT TONIGHT/EARLY SUNDAY AS A WAVE
MOVES UP ALONG IT. QG FORCING AND THERMAL/MOISTURE GRADIENTS SUGGEST
THAT AN MCS SHOULD DEVELOP ACROSS NEBRASKA WHICH WOULD ANCHOR THE
FRONT INITIALLY AND THEN MOVE IT EAST. SUNDAY FRONT SLOWLY
APPROACHES THE AREA AND THUS WILL INTRODUCE POPS FROM WEST TO EAST
USING AFTERNOON/LATE IN THE DAY WORDING.
MAIN PRECIPITATION EVENT TO OCCUR SUNDAY NIGHT/MONDAY AS COLD FRONT
SLOWLY MOVES THROUGH THE FORECAST AREA WITH ADDITIONAL WAVES
TRAVELING ALONG IT. GOOD DRYING/DOWNWARD MOVEMENT BEHIND THE FRONT
INDICATES CLEARING SKIES FROM WEST TO EAST DURING THE DAY MONDAY.
FWC/FAN ARE A GOOD STARTING POINT FOR TONIGHT BUT WILL GO ABOVE
GUIDANCE FOR TONIGHT AND MAKE ADJUSTMENTS ACCORDINGLY FOR LATER
PERIODS.
...EXTENDED...
HIGH PRESSURE TO BUILD INTO THE AREA MONDAY NIGHT/TUESDAY ALLOWING
THE ONLY QUIET PERIOD OF WEATHER. CURRENT SHORTWAVE/JET STREAK SOUTH
OF THE ALEUTIANS TO BE THE FOCUS FOR THE START OF ACTIVE WEATHER FOR
THE WEDNESDAY/THURSDAY TIME PERIOD. WEDNESDAY/THURSDAY TIME PERIOD
COULD GET QUITE INTERESTING AS THIS SHORTWAVE AMPLIFYS. FAIRLY
WIDESPREAD CONVECTIVE RAINS APPEAR LIKELY WITH AMOUNTS BEING
MODERATE TO POSSIBLY HEAVY.
COORDINATED WITH DSM...LSE...CHI...SPI...STL.
.DVN...NONE.
NC
ia
AREA FORECAST DISCUSSION..UPDATED..
NATIONAL WEATHER SERVICE TAUNTON MA
1115 AM EDT SAT JUN 26 1999
NO SIG CHANGES TO THE EARLY AM PKG EXCEPT TO DROP THUNDER FM PVD AND
CAPE COD AND LEAVING SLIGHTEST CHC THUNDER EWB-UUU-WESTERLY WHERE CNV
OCCURS ALONG DRY LINE. DRYING ALOFT PROBABLY OVERWHELMS AND NEGATES
WITH CT UP NR 99F THIS AFTN...THUNDER NOT LIKELY IN OUR CWA.
MAX TEMP THIS AFTN COASTAL PLAIN AND INTERIOR VALLEYS (NON
MARINE-INFLUENCED) 92-95 PER 15Z MWN WB OF 52 AND 12Z ETA FCSTG
29C 1000 MB TEMP THIS AFTN IN HOT WNW SFC FLOW. NO RECORD TEMPS
SINCE RECORDS ARE NR 100F.
SEABRZ NOT FCST (NOT IMPOSSIBLE TO OCCUR) COASTAL E MA THIS AFTN BUT
TURNING OF WINDS TO SSW LIKELY ABOUT 10 MI OUT IN THE WATERS PER
09Z AND 12Z RUC SFC WIND FCSTS. LESS WIND OUTER WATERS THAN ALONG THE
MORE UNSTABLE IMMEDIATE COAST.
WIND OVER THE INTERIOR (BAF/ORE/ORH) SHOULD GUST 22-26 KT FOR A 1-3
HR PRD CENTERED ON 18Z PER DRY UNSTABLE ALY SOUNDING SFC TO 8K.
FLAGGED POTENTIAL OF THIS IN ETA TRANSFER MACRO.
UNCOMFORTABLY HUMID SIGNAL MONDAY AS NGM R1 FLOODS 90-99% RANGE ALL
SNE 12Z MONDAY...SUGGESTING PATCHY DENSE FOG PREDAWN MONDAY ON DECENT
SLY FLOW.
WATER TEMPS THIS AM ON AND NEAR CC NATIONAL SEASHORE
RACE POINT 61F
HERRING COVE 64F
MARCONI 55F
.BOX...NONE.
DRAG
ma
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
300 AM EDT SUN JUN 27 1999
CHALLENGE TODAY IS POPS WITH ASSOCIATED COLD FROPA...
500MB FLOW CHARACTERIZED BY RIDGE OVER E CONUS AND TROF OVR GREAT
BASIN. COLD FRONT EXTDS S TO NW WI-SE MN FROM 1003MB SFC LO OVR S
ONTARIO AT 06Z. IR IMAGERY/88D SHOW CONVECTION ASSOC WITH FRONT
CONTINUING TO DIMINISH AT 06Z WITH WARMING CLOUD TOPS. ANOTHER AREA
OF SHRA/TSRA CONTINUES TO MOVE NE ACROSS WEST CENTRAL LOWER MI AND
LK MICHIGAN...WITH W EDGE OF SHIELD CLIPPING NEAR LK MI NEAR SHORE.
THIS AREA OF PRECIP APPEARS TO BE SUPPORTED BY SHRTWV ENERGY OVR S
LK MI...AND UPR LVL DIV IN RRQ OF JET STREAK OVR ONTARIO.
COLD FRONT PROGGED TO CROSS CWA FROM W TO E TODAY. GIVEN TIMING OF
PASSAGE...BEST OPPORTUNITY FOR SHRA/TSRA WILL BE OVR E CWA. RUCS
PRS/WND FIELDS DEPICT FRONT FROM MUNISING-IMT BY 18Z WITH BEST LOW
LEVEL MOISTURE POOLED E OF FRONT WITH DEWPOINTS IN UPR 60S OVR SE
CWA. ETA/RUC ALSO SHOWING 850 THETA-E RIDGE NOSING INTO
MNM-ESC...INCREASING SFC CONV AND BNDRY LYR LI'S IN -3 TO -5C. ETA'S
POS BOUY ENERGY'S OF 1600J/KG BETWEEN 18-21Z. SOLAR HEATING ONLY TO
BE LIMITED MARGINALLY BY HI CLOUDS. WBZ PROGGED TO BE ABOUT 9K-10K
FT BY ETA...SUGGESTING HAIL A THREAT WITH ANY TSRA THAT DO DEVELOP.
JET DYNAMICS ALSO COME INTO PLAY AS 100KT JET STREAK POSTIONS E CWA
IN RRQ BY 21Z. GIVEN LOCATION OF PARAMETERS HIGHEST THREAT FOR
STRONG/POSSIBLY SVR TSRA WILL BE MNM-ESC.
COLD FRONT EXITS CWA BY 00Z MONDAY AS NEXT SHORTWV EJECTS FROM
ROCKIES AND APPROACHES CWA DURING MONDAY. MODELS CONTINUE IN
DISAGREEMENT WITH EVOLUTION OF SHORTWAVE ENERGY AND ASSOC SFC
REFLECTION WITH AVN/NGM DEVELOPING EJECTING LO THAT RIDES NE ON OLD
FRONTAL BDRY...DEEPING AS IT MOVES THROUGH E LKS INTO CANADA. ETA
CONTINUES TO OFFER MUCH WEAKER SOLUTION...AND IS PREFERED BY NCEP.
GIVEN SUPPORT OF STONGER SOLN BY ECMWF...AM NOT WILLING TO TOTALLY
DISCARD AVN/NGM. WILL RETAIN SHRA ON MONDAY. WEAK RIDGING OVR CWA
TUESDAY...WITH NEXT SHORTWAVE IN PROGRESSIVE FLOW BRINGING NEXT
CHANCE OF SHRA/TSRA WITH RETURN FLOW OFF GULF BY LATE WEDESDAY/THURS.
.MQT..NONE.
WOLF
FXUS63 KGRR 270809 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
408 AM EDT SUN JUN 27 1999
AREA OF STRONGEST CONVECTION NOW MOVING N/NE INTO N CENTRAL LOWER MI
IS LINING UP VERY WELL WITH HIGHER DWPTS RIDGING INTO THIS REGION
AND A NOSE OF LOWER LI'S IN THIS VCNTY PER LATEST LAPS ANALYSIS.
WIND FIELDS ARE QUITE WEAK AND FZL IS AROUND 15 KFT...SO DO NOT
EXPECT SVR HAIL AND/OR GUSTS THIS MORNING. ALSO...AIRMASS OVER NRN
LOWER IS STILL FAIRLY DRY AND STABLE...AND HAVE NOTED A GENERAL
DECREASE IN BASE REF AS STORMS MOVE N THROUGH THE CWA. MAIN FORECAST
CONCERN FOR THE SHORT TERM REVOLVES AROUND THIS AREA OF PRECIP.
LATER PERIODS TURN TOWARD AFFECTS OF COLD FROPA LATER TODAY/TONIGHT
AND THEN UNCERTAINTY OF THE EVOLUTION OF A DEVELOPING SHORT WAVE
ALONG THE FRONT FOR MONDAY DUE TO MODEL INCONSISTANCIES.
MODELS DIFFER WILDLY AFTER 24 HOURS WITH RESPECT TO THE EVOLUTION OF
THE NEXT SHORT WAVE AND SFC SYSTEM. ETA TRIES TO HOLD THE DEVELOPING SFC
LOW IN THE CENTRAL PLAINS AT BAY...WHILE THE NGM AND AVN BOTH DRIVE
THE SFC NE TOWARD THE SRN GREAT LAKES AS IT FURTHER DEEPENS. NGM
CONTINUES TO PROVIDE A HIGHER AMPLITUDE SOLUTION IN THE LONG WAVE
PATTERN OVER THE CENTRAL US. AS A RESULT...NGM PROGS JET COUPLING
OVER THIS AREA BETWEEN THE DEPARTING JET MAX TO THE NE AND ANOTHER
JET MAX DIVING SE INTO THE CENTRAL PLAINS...THUS CREATING A DEEPER
SFC RESPONSE. TENDING TO STEER AWAY FROM THE UNSEASONABLY DEEP SFC
LOW PROVIDED BY THE NGM SOLUTION...BUT THINK THE ETA MAY BE TOO
PROGRESSIVE. AVN IS A GOOD COMPROMISE BETWEEN THE TWO...WITH REALITY
LIKELY FALLING SOMEWHERE BETWEEN THE ETA AND AVN.
FOR TODAY...WILL GO WITH CATEGORICAL POPS FOR SE CWA FROM HTL TO
TAWAS TO GLADWIN IN THE MORNING BASED ON CURRENT RADAR TRENDS AND
LATEST RUC THETA E RIDGE POSITIONING. WILL TAPER TO CHANCE POPS FOR
THE AFTERNOON IN THIS AREA AND FOR THE REMAINDER OF THE CWA AS THE
COLD FRONT WILL LIKELY PROVIDE ENOUGH LOW LEVEL CONVERGENCE TO KICK
OFF ANOTHER ROUND OF SCT SHRA/TSRA.
SECONDARY SHORT WAVE DEVELOPS ALONG THE FRONT OVER THE NRN AND CENTRAL
PLAINS LATE TONIGHT AND MOVES E/NE INTO THE SRN GREAT LAKES ON
MONDAY. WILL DECREASE POPS TO CHANCE FOR TONIGHT AS THE FRONT STALLS
WITH VERY LITTLE IN THE WAY OF UPPER SUPPORT TO WARRENT WIDESPREAD
PRECIP. WILL MAINTAIN LIKELY POPS FOR MONDAY AS THE SHORT WAVE
ENTERS MI.
.APX...NONE
EME
FXUS63 KDTX 270727 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
100 AM EDT SUN JUN 27 1999
UPDATED ALL BUT FAR NE LOWER MI ZONES TO INCREASE AND/OR ADD POPS
BASED ON CURRENT RADAR TRENDS. ELONGATED AREA OF SHRA NOW MOVING
N/NE THROUGH THE WI WATERS OF LAKE MI WILL IMPACT FAR NW LOWER AND
ERN UPR ZONES LATE TONIGHT. ANOTHER AREA OF SHRA/TSRA IS MOVING N/NE
THROUGH SW LOWER MI TOWARD N CENTRAL LOWER MI FROM NEAR CAD TO HTL
ATTM. A GENERAL DOWNWARD TREND HAS BEEN NOTED AS THE PRECIP MOVES N
INTO A DRIER MORE STABLE AIRMASS AS NOTED ON THE 00Z APX SOUNDING...
BUT SHRA/TSRA IS HOLDING TOGETHER ENOUGH TO WARRENT MENTION OF SCT
POPS THROUGH SUNRISE. LATEST RUC ALSO SHOWS A NOSE OF LOWER LI'S
PUNCHING N INTO N CENTRAL LOWER MI WHICH SEEMS TO MATCH UP WELL WITH
CURRENT RADAR TRENDS.
.APX...NONE
EME
FXUS63 KAPX 270233 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1000 PM EDT SAT JUN 26 1999
LATEST IR/VAPOR VAPOR IMAGERY SHOWS MID TROPOSPHERIC CIRCULATION IN
NORTHERN ILLINOIS...ALONG WITH AREA OF CONVECTION THAT CONTINUES
NEAR THE SOUTHERN END OF LAKE MICHIGAN. IN ADDITION...SOME SHOWER
ACTIVITY EXTENDS NORTH ALONG THE LAKE MICHIGAN SHORELINE OF
WISCONSIN...AS WELL AS SOME CONVECTION THAT HAS FIRED UP THIS
EVENING IN SOUTHWEST LOWER. FORECAST CONCERN FOR OVERNIGHT HOURS
REVOLVES AROUND PRECIPITATION CHANCES MAINLY FOR THE SOUTHERN TIER
OF COUNTIES.
00Z APX SOUNDING SHOWS STRONG SUBSIDENCE INVERSION IN PLACE AROUND
THE 750 MB LEVEL...ALONG WITH VERY DRY AIR EXTENDING TO AROUND 400
MB. LOW LEVEL MOISTURE STILL REMAINS MARGINAL...ALTHOUGH LAST FEW
HOURS OF OBSERVATIONS ARE BEGINNING TO SHOW INCREASING SURFACE
DEWPOINTS WORKING INTO SOUTHWEST PART OF CWA.
LATEST RUC BRINGS DECENT AREA OF DPVA INTO NORTHWEST LOWER MICHIGAN
BY 09Z. HOWEVER...WITH DRY AIR ALOFT AND WITH MARGINAL LOW LEVEL
MOISTURE AVAILABLE...STILL FEEL THAT SCATTERED POPS ARE A GOOD BET
FOR SOUTHERN TIER OF COUNTIES OVERNIGHT. RUC SHOWS BETTER AVAILABLE
LOW LEVEL MOISTURE ACROSS SOUTHEAST COUNTIES AFTER 09Z...SO WILL
ALSO KEEP SCATTERED POPS IN FOR SOUTHEAST COUNTIES...BUT WILL CHANGE
WORDING TO BRING RAIN CHANCES IN LATE.
TEMPERATURES APPEAR ON TARGET FOR THE MOST PART. WILL ONLY TWEAK IN
A FEW SPOTS TO REFLECT CURRENT TRENDS.
.APX...NONE
ADAM
FXUS63 KMQT 270158 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
210 AM EDT SUN JUN 27 1999
PRECIP MOVING ACROSS NRN AND WRN GA APPEARS TO BE ASSOC WITH A SMALL
SHORTWAVE AND ASSOCIATED DPVA WHICH THE 03Z RUC PUSHES INTO NE GA
AND THE WESTERN CAROLINAS AFTER 09Z. MORE IMPRESSIVE WAVE SEEN IN WV
IMAGERY OVER WRN TN TO MOVE ENE TODAY...BRINGING THE TROUGH AXIS
THROUGH CWA IN THE 00-06Z TIME FRAME. NGM/AVN A LITTLE SLOWER WITH
ITS PASSAGE...BUT I TEND TO LEAN MORE TOWARD THE ETA SINCE WE ARE IN
A NEARLY ZONAL FLOW. REGARDLESS...HIGH SFC DWPT AIR AND TONS OF
MESO-SCALE BOUNDARIES SITTING AROUND SHOULD BE SUFFICIENT FOR THE
UPPER WAVE AND WEAK DIVERGENCE TO WORK WITH TO CAUSE NUMEROUS
SHOWERS AND THUNDERSTORMS TODAY. WILL GO CATEGORICAL POPS IN THE
MTNS AND HIGH LIKELY ELSEWHERE. CONVECTIVE ACTIVITY SHOULD ABATE
TONIGHT WITH PASSAGE OF TROUGH AXIS AND ENSUING SUBSIDENCE AND
DRYING IN THE MID/UPR LAYERS. ALTHOUGH...THE INITIAL SURGE OF MID
LEVEL DRYING COULD ENHANCE SOME OF THE CONVECTION EARLY IN THE
EVENING. WITH SO MUCH MOISTURE AVAILABLE IN THE ATMOS...WILL MENTION
LOCALLY HEAVY RAIN FOR THE MTNS.
MONDAY APPEARS TO BE A LITTLE QUIETER WITH WEST TO NORTHWESTERLY
FLOW ABOVE THE BOUNDARY LAYER IN THE WAKE OF THE TROUGH AND NO
SHORTWAVE ENERGY TO AFFECT THE REGION UNTIL LATER MONDAY NIGHT.
HOWEVER...ADDITIONAL MOISTURE IN THE MID-LEVELS MOVES BACK OVER THE
AREA AND LOW LEVELS REMAIN VERY MOIST. SO SCATTERED CONVECTION
CERTAINLY POSSIBLE...PER CURRENT ZONE FORECAST.
EXPECT TO SEE TEMPS CLOSE TO YESTERDAYS TODAY. THEN A LITTLE WARMER
MONDAY. STUCK CLOSE TO GUIDANCE TODAY AND A LITTLE COOLER THAN MOS
MONDAY.
PRELIMINARY CCF...
AVL 078/068 083/069 085 26944
CLT 085/071 087/072 089 26774
GSP 084/072 087/071 090 26764
.GSP...NONE.
MOYER
FXUS62 KGSP 270158 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
945 PM EDT SAT JUN 26 1999
KGSP RADAR SHOWS TSRA CONTINUING ACROSS THE NC FOOTHILLS/PIEDMONT...
BUT ONLY DISSIPATING LITE RAIN ACROSS THE MOUNTAINS AND UPSTATE SC. FOR
THE SHORT TERM...EXPECT MOST OF THE DEEP CONVECTION TO CONTINUE N OF AN
AVL/CLT LINE AS IT DEVELOPS NORTHWARD INTO AN UNUSED AIR MASS ACROSS
THE NW PIEDMONT OF NC. THIS PARTICULAR CONVECTION SHOULD DIMINISH
TOWARD MIDNITE. WOULD LIKE TO UPDATE ZONES TO LOWER SOME OF THE PRECIP
CHANCES...BUT AM NOT SURE THAT WOULD BE THE BEST COURSE OF ACTION FOR
THE ENTIRE FCST AREA. ALTHOUGH MAIN FORCING FROM VORT CENTER SEEN IN
WATER VAPOR IMAGERY MOVING OVER WRN TN/NWRN MS SHOULD REMAIN TO OUR W
OVERNITE...LATEST RUC SHOWS LOW LEVEL FORCING MOVING ACROSS CENTRAL GA
AND TOWARD THE UPSTATE EARLY SUNDAY. IN RESPONSE...THE RUC SHOWS AN
AREA OF PRECIP MOVING BACK IN TOWARD NE GA/UPSTATE SC BY 09Z. FOR THAT
REASON...WILL NOT SIGNIFICANTLY LOWER PRECIP CHANCES.
.GSP...NONE.
MOORE
FXUS62 KCHS 270109 sc
COASTAL BEND FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
250 AM CDT SUN JUN 27 1999
CRP 00Z SOUNDING INDICATED SAME MOIST UNSTABLE AIRMASS IN PLACE.
PWAT ARE EVEN A TAD HIGHER THAN 24 HRS AGO. MODERATE SURFACE TO
800MB WINDS...HOWEVER ARE INHIBITING MORE WIDESPREAD PRECIP. DOPPLER
RADAR INDICATED WIDELY SCATTERED LIGHT SHOWERS OFFSHORE STREAMING
NORTHWARD INLAND TOWARD THE PORT LAVACA AREA. MSAS SHOWS CONVERGENCE
CONTINUES ALONG THE MIDDLE AND UPPER TX COAST. RUC INDICATED VORT
MAX IN SAME LOCATION. EXPECT THIS ACTIVITY TO INCREASE TOWARD
SUNRISE THEN DECREASE AS WINDS INCREASE THIS AFTERNOON.
PWAT PROGD TO DECREASE TODAY AND MONDAY AS UPPER RIDGE CONT TO BUILD
OVER TX...BRINGING IN LOWER RH VALUES TO MID AND UPPER LEVELS. WV
SATELLITE SHOWS THE UPPER RIDGE BUILDING OVER TX QUITE WELL. ETA
TIME SECTION ALSO PROGS DRYING IN THE MID AND UPPER LEVELS. MODELS
KEEP BREEZY CONDITIONS FORECAST THROUGH MONDAY AS SFC LOW TREKS
ACROSS PLAINS AND TOWARD GREAT LAKES AND SFC HIGH PRESS BUILDS EAST
TO WEST OVER GULF RESULTING IN A TIGHT PRES GRADIENT. TEND TO AGREE
WITH MODELS IN DECREASING POPS THROUGH 48 HRS DUE THESE FEATURES.
EXTENDED...TOWARDS END OF WEEK...MRF PROGS UPPER RIDGE TO RETREAT
WESTWARD AS UPPER TROF SWEEPS EASTWARD ACROSS NORTHERN PLAINS AND A
HINT OF A TROPICAL APPROACHES EASTERN MEXICO/DEEP S TX. IF THIS
HOLDS...NEXT 4TH OF JULY WEEKEND COULD BE WET. MRF ALSO PROGS A
SECOND TROPICAL WAVE TO TREK WEST ACROSS GULF BY EARLY NEXT WEEK.
MARINE...SCA TODAY AND MONDAY FOR THE BAYS...SCEC OFFSHORE.
PRELIMS...
CRP BB 092/078 093/079 093 211
NGP 090/081 091/081 091
ALI 094/078 096/077 096
VCT BB 090/078 092/077 092 211
LRD BB 098/078 100/077 100 21-
.CRP...SCA IN EFFECT FOR GMZ230-235 (BAYS) TODAY.
81/TP...86/GW
FXUS64 KHGX 270744 tx
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
245 AM CDT SUN JUN 27 1999
VERY HIGH PWS OVER AREA (AT OR ABOVE 2 INCHES) INDICATED BY LAST
NIGHTS SURROUNDING SOUNDINGS. ANALYZED 27/00Z UPPER LEVEL SHOWS 19
DEG DEWPOINTS AT 850 MB CRP AREA. SHEAR AXIS EVIDENT AT MID LEVELS
(700-500 MB). MODELS INDICATE AXIS WILL HANG ON OVER REGION NEXT TWO
DAYS WITH SLIGHT SE MOVEMENT BY LATE MONDAY AS UPPER HIGH OVER SW
U.S./NORTHERN OLD MEXICO EXPANDS SOMEWHAT EASTWARD. AVN AND NGM MORE
AGGRESSIVE DAY ONE WITH MOISTURE AND UVM AND ETA SOMEWHAT LESS.
1000-700 MB MEAN RH LOWERING IN DEPTH FROM LATE MONDAY TO TUESDAY BY
AVN INDICATING WEAK SUBSIDENCE ABOVE 700 MB. RUC INDICATE LOW LEVEL
SPEED CONVERGENCE TODAY NEAR COASTAL SECTIONS. THIS WOULD INDICATE A
ROBUST SEA BREEZE SETTING UP. THIS WILL BE THE FOCUS FOR CONVECTIVE
DEVELOPMENT. WILL PUT SCATTERED CONVECTION IN FORECAST TODAY BECOMING
ISOLATED DURING EVENING . WITH WEAK SUBSIDENCE ALOFT ON MONDAY AND
70 PERCENT MEAN RH BECOMING SHALLOWER...WILL GO WITH WIDELY
SCATTERED MONDAY.
.HGX...NONE.
37/46
PRELIMS...
CLL BB 094/077 094/077 095 3221
IAH EB 093/077 094/077 095 4221
GLS EB 089/082 090/082 090 4221
FXUS64 KMAF 270731 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
243 PM CDT SAT JUN 26 1999
RATHER HIGH SURFACE DEWPOINTS...SHOWING SUMMER IS DEFINITELY HERE WAS
NOTED OVER THE COUNTY WARNING AREA EARLY THIS AFTERNOON. EXCEPT FOR
THE MTNS...HAD DEWPOINTS IN THE 60S...WITH LATE MORNING 70 READINGS
FROM INK TO CNM. AT THE SURFACE...A TROF WAS NOTED EXTENDING FROM
BETWEEN CAO/DHT...TO WEST OF ROW...TO AROUND GDP. EARLIER...OUR 12Z
RAOB INDICATED 7H TEMPS AT +15C...BUT 5H TEMPS HAD COOLED TO
-10C...MAKING FOR STEEP MID-LEVEL LAPSE RATES. THIS WAS CAUSING AN
AREA OF AC/ACC CLOUDS JUST NW OF HERE EARLIER. THE STRONG CAPPING
APPEARS TO BE HOLDING STRONG FOR THE PERMIAN BASIN...BUT TERRAIN
EFFECTS WAS CAUSING STORMS TO FIRE IN THE SACRAMENTO...GUADALUPE...
AND DAVIS MTNS.
THROUGH THE EVENING...MID-LEVEL CAPPING SHOULD HOLD FOR THE LOWLANDS
THUS DRY CONDITIONS WILL CONTINUE. THE 18Z RUC...ALONG WITH THE 12Z
MODELS SHOW 7H TEMPS SHOULD REMAIN AT LEAST 15C...WITH 5H TEMPS
WARMING TO THE -6 TO -7 RANGE. WILL NOTE ISOLATED TO WDLY SCATTERED
CONVECTION IN THOSE FAVORED PLACES. WITH NOT MUCH CHANGE EXPECTED...
WILL GO FOR A SIMILAR FORECAST TOMORROW AND MONDAY. GOING ALONG WITH
OUR MORNING UPDATE...WILL ADD MENTION OF MORNING LOW CLOUDS FOR MOST
OF THE PERMIAN BASIN. GULF MOISTURE MADE FURTHER NW PROGRESS THAN 1ST
THOUGHT YSTRDY...AND A SIMILAR SOLUTION SUGGESTED IS TMRW MORNING.
FOR THE EXTENDED...MEAN TROFFING AND THE NORTHERLY JET MAX WILL DROP
FURTHER SOUTH. THUS WILL INTRODUCE ISOLATED TO WDLY SCATTERED POPS
MAINLY FOR THE NORTHERN PERMIAN BASIN TUESDAY...AND KEEP THE REST OF
THE FLATLAND AREAS DRY. FROM OROGRAPHIC EFFECTS...WILL KEEP A CHANCE
OF CONVECTION IN THE MTNS.
WILL GO ABOVE MODEL TEMPS...ESPECIALLY THE TOO COOL NGM. WORK ZONES
FOR THIS EVENING ARE ON THE WAY. 1ST GUESS NUMBERS BELOW.
MAF 71/101/70/103 -/0/-/0
CNM 70/103/71/104 1/-/1/-
MRF 61/94/61/94 1/-/1/-
P07 73/96/74/97 -/0/-/0
RSB
FXUS74 KEWX 261934 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN, FL
945 AM EDT SUN JUN 27 1999
CONSIDERABLE MID LEVEL DRYING IS SHOWING UP ON THIS MORNINGS
SOUNDING AND 2 QUESTIONS COME TO MIND IMMEDIATELY. ONE WHY IS IT
THERE AND 2 WHAT EFFECT WILL IT HAVE ON TODAYS WEATHER. MY FIRST
THOUGHT IS THAT IT IS SUBSIDENCE OUT AHEAD OF THE CONVECTION THAT
MOVED THROUGH THE PANHANDLE YESTERDAY AND LAST NIGHT. NOW HOW WILL
IT EFFECT TODAYS WEATHER...I WOULD THINK THAT WE WILL SEE A LITTLE
HIGHER TEMPERATURES AND AN INCREASED POTENTIAL FOR DOWNBURSTS AND
SMALL HAIL. LOOKS LIKE IT HAS ALREADY PUT A DAMPER ON NOCTURNAL
CONVECTION...BUT WE WILL HAVE PLENTY OF CAPE ONCE AFTERNOON HEATING
GETS UNDERWAY TO GIVE US GOOD THUNDERSTORM COVERAGE.
K INDEXES WOULD SUPPORT LOWERING POPS A BIT...BUT I THINK THAT IS
MISLEADING BECAUSE SUBSIDENCE AND DRYING IS RIGHT AT THE CRITICAL
850 MB LEVEL FOR THE K INDEX. THIS WILL CHANGE AS THE 09Z RUC HAS
ANOTHER SHORT WAVE MOVE IN EARLY THIS AFTERNOON...ESPECIALLY OVER
THE NORTHERN ZONES WHICH WILL SEE INCREASED MIXING DUE TO THE SHORT
WAVE. WARMER TEMPERATURES DUE TO THE DRYING WILL ALLOW THE SEABREEZE TO
BE A LITTLE MORE VIGOROUS. THIS WILL KEEP ACTION A LITTLE FARTHER
INLAND THAN YESTERDAY. EXCEPT IN THE FT MYERS AREA...WITH THE RIDGE
AXIS NEAR LAKE OKEECHOBEE A FEW THUNDERSTORMS COULD MOVE BACK INTO
THAT AREA LATER TODAY WITH THE LIGHT EASTERLY FLOW.
TO SUM IT UP...A SHORT WAVE MOVING ACROSS THE NORTH...WILL MAKE
ACTIVITY MORE WIDESPREAD THERE. BUT A DRY LAYER IN MID TO LOW
LEVELS WILL NOT BE ABLE TO MIX OUT BEFORE CONVECTION REALLY STARTS
FIRING UP IN THE SOUTH. DRYING WILL ALLOW TEMPERATURES TO INCREASE
MAKING FOR A MORE VIGOROUS SEABREEZE...KEEPING MOST OF THE COASTAL
AREAS RAIN FREE. I WILL ADJUST THE FORECAST AND HWO ACCORDINGLY.
SOBIEN
FXUS62 KEYW 271342 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
845 AM EDT SUN JUN 27 1999
LATEST SURFACE ANALYSIS SHOWS AREA OF MOISTURE FLUX DIVERGENCE
ACROSS THE CWA. AT MID LEVELS...WATER VAPOR LOOP SHOWS PLENTY OF MID
LEVEL MOISTURE ACROSS THE AREA WITH RIDGE OVER THE NORTHERN GULF AND
S/W MOVG INTO MS. 88D SHOWG BAND OF MODERATE RAIN WITH SOME
ISOLATED CONVECTIVE CELLS MOVG ACROSS SE GA ATTM. COMPARISON OF THE TWO
MESOSCALE MODELS...MESOETA AND RUC...SHOWS THAT RUC HAS A BETTER
HANDLE OF THIS SITUATION THAN THE MESOETA. SO THAT IS OUR MODEL OF
CHOICE FOR THE SHORT TERM. PCPN ACROSS S GA ATTM IS MOSTLY IN
RESPONSE TO WEAK UPR LVL FORCING DEPICTED BY THE Q VECTOR FIELD TO
THE WEST OF THE CWA. AREA OF RAIN SHOULD CONTINUE TO WEAKEN DURING
THE MORNING AS IT MOVES INTO AREA OF SFC MSTR FLUX DIV.
12 SNDZ SHOWS A BIT OF A DRIER ATMOSPHERIC COLUMN THIS MORNING THAN
YESTERDAY. WET BULB ZERO IS 12900 (MORE THAN 1000 FT LWR THAN
YESTERDAY) WITH PW OF 1.8 OR ABOUT .3 INCHES LESS THAN YESTERDAY.
MODIFIED CAPES ARE ABOVE 2000 J/KG. THE LOWER WET-BULB IS IN RESPONSE
TO SOME DRY AIR INTRUDING ABOVE H7 AND GIVEN THE LATEST WATER VAPOR
LOOPS I DO NOT SEE THAT CHANGING MUCH. SO GIVEN THIS SCENARIO THE
POTENTIAL CONTINUES FOR HEAVY RAINNERS AND SOME SMALL HAIL. A FEW
STRONG THUNDERSTORMS CAN NOT BE RULED OUT ESPECIALLY IN AREAS WHERE
HEATING IS GREATEST.
ZONE FORECAST LOOK ON TRACK FOR BOTH GA AND FL. DO NOT PLAN
AMENDMENTS ATTM. JUDGING PER THE AREA BUOYS...CWF LOOKS ON TRACK.
SANTOS
FXUS62 KTBW 270725 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1040 AM CDT SUN JUN 27 1999
14Z SFC ANALYS PLACES FRONTAL BNDRY FM WISCONSIN THRU IOWA ROUGHLY
ALG A LINE FM KLSE-KMIW-KCSQ. SHRA/TSRA DECREASING SOME IN AREAL
COVERAGE AS THEY WORK ACRS CNTRL IOWA. DENSE CIRRUS SHIELD FM ACTVTY
ENVELOPING MUCH OF CWA. KMDX WSR-88D SHOWS MCV OVR SCNTRL IOWA WITH
NEW DVLPMNT NR KOTM-KFFL AND OTHER ISOLD DVLPMNT OVR NCNTRL ILLINOIS.
WL BE SENDING OUT UPDATE SHORTLY TO ACCOUNT FOR RECENT CONVECTIVE
TRENDS. WL LIKELY ADD MENTION OF HVY RAIN DUE TO HIGH PW/S AND
RELATIVELY SLOW MOVEMENT. SVR THREAT LUKS MINIMAL DUE TO WEAK WIND
FIELDS THUS MAIN THREAT WL BE VERY HEAVY RAINS. MAY ALSO MAKE
SOME MINOR ADJUSTMENTS TO TEMPS TONING THEM DOWN A NOTCH DUE TO
CLOUDS/PCPN. LTST RUC BRINGS FNT TO NEAR MISSISSIPPI RVR SO WL BRUSH
UP WNDS AS WELL.
.DVN...
IA...NONE.
IL...NONE.
05
FXUS63 KDVN 270808 ia
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1100 AM EDT SUN JUN 27 1999
*********************************************************************
STARTING 15 JULY 1999 AT 9 AM...THE NAME OF THIS PRODUCT WILL
CHANGE.
OLD NWWS ID OLD FOS ID NEW NWWS ID NEW FOS ID
CRWSFDCRW FXUS71 KRLX CRWAFDRLX FXUS61 KRLX
*********************************************************************
SO...HOW IS THE RAIN GOING TO MISS US THIS TIME? IT DOESNT LOOK
LIKE IT WILL BUT IT DOES HAVE A SMALL CHANCE TO.
DOUBLE BARREL VORT STRUCTURE NOT RESOLVED ON YESTERDAYS MODELS
PICKED UP TODAY WITH ONE VORT AND ASSOCIATED SURFACE LOW LOCATED
NEAR ELKTON KENTUCKY AND THE OTHER VORT IN NORTHERN INDIANA. GOT TO
LOOK AT 12Z RUC AND 12Z ETA TO 24HRS AND THEY TEND TO ELONGATE THE
SOUTHERN VORT AND MOVE IT ACROSS THE AREA THIS AFTERNOON AND
EVENING. (21-09Z). THE DIFFERENCE FOR THIS EVENT THAN PREVIOUS
EVENTS (EVEN THOUGH THERE IS NOT MUCH SURFACE FORCING) IS THAT LOWER
TO MID 70 SURFACE DEW POINTS ARE ADVECTING IN AND THERE IS NOT A STRONG
SOUTHEAST DOWNSLOPE FLOW TO DRY IT OUT. WINDS ARE BECOMING MORE
SOUTHWEST. AND TO HELP OUT...LATEST VISIBLE LOOP IS SHOWING BREAKS
IN THE CLOUDS AHEAD OF THE PVA IN ERN TN. THIS HEATING SHOULD
DESTABILIZE THE ATMOSPHERE ENOUGH TO RING OUT SOME GOOD RAINS FROM
2.00 INCH PRECIPITABLE WATER FILLED AIR. WILL KEEP THE MENTION OF
HEAVY DOWNPOURS POSSIBLE BECAUSE OF THIS. THERE ARE NO FLOODING
WORRIES BECAUSE FFG IS MAXED OUT AT 2.3 INCHES IN AN HOUR. 2.3 IN
AN OUR WOULD CAUSE SOME POOR DRAINAGE FLOODING BUT THAT ABOUT IT IN
OUR BONE DRY GROUND.
WRKZFP ALREADY OUT. ZONES TO FLY SOON.
.CRW...
WV...NONE.
VA...NONE.
KY...NONE.
OH...NONE.
.END / DJR
FXUS63 KJKL 271450 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
1055 AM EDT SUN JUN 27 1999
14Z SFC ANALYSIS SHOWS A WEAK LOW CENTER OVER SOUTH WESTERN KENTUCKY.
THIS IS ASSOCIATED WITH A WELL DEFINED VORT MOVING THROUGH THE STATE
WITHIN A TROUGH. DEEPER CONVECTION FROM THIS IS POISED TO MOVE INTO OUR
CWA ESPECIALLY IN THE SOUTHEAST. THE RUC AND MESOETA SPLIT THE VORT
RUNNING ONE SECTION TO THE SOUTHEAST OF JKL AND THE OTHER TO THE NORTH.
THE PRECIPITATION PRINTOUT BY THE NEAR-TERM MODELS REFLECT THIS SPLIT.
WITH THE CLOUD COVER AND NO REAL LOW LEVEL FOCUSING MECHANISM WILL
LEAVE HEAVY RAIN OUT OF THE AFTERNOON FORECAST...HOWEVER...THE SLOW
NATURE OF THE SHOWERS WILL MAKE LOCALLY HIGH AMOUNTS POSSIBLE FROM ANY
STRONG CELL. CURRENT FORECAST HAS THE PRECIPITATION CHANCES WELL IN
HAND. THE ONLY THING I WOULD ADD WILL BE A DEVELOPING MODIFIER.
TEMPERATURES LOOK FINE AS WELL WITH A RANGE APPROPRIATE GIVEN THE
BREAKS APPEARING THE IN THE CLOUD COVER AHEAD OF THE MAIN AREA OF RAIN.
WILL LET THE CURRENT FORECAST RIDE AND FOCUS ON TIMING THE
PRECIPITATION IN THE NOWS.
.JKL...NONE.
GREIF
FXUS63 KJKL 270812 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1125 AM EDT SUN JUN 27 1999
BIG QUESTION THIS UPDATE DEALS WITH SHRA/TSRA ASSOCIATED WITH
SURFACE TROUGH/COLD FRONT MOVING THROUGH THE FORECAST AREA. KMQT
88-D/LDS DATA INDICATES SCATTERED SHOWERS AND THUNDERSTORMS OVER THE
WESTERN CWA.
12Z RUC INDICATES SOME INSTABILITY ACROSS THE FORECAST AREA WITH
SHOWALTER INDICES IN THE -1 TO -3 RANGE AND BOUNDARY LAYER LIS OF -2
TO -4 ACROSS THE SOUTHERN COUNTIES. 03Z MESOETA BRINGS CAPES OF UP
TO 2000 J/KG INTO THE SOUTHERN COUNTIES. GRB SOUNDING MODIFIED FOR
MID 80S/UPPER 60S TEMP/DWPT YIELDS A CAPE AROUND 1600 J/KG. AS THE
COLD FRONT MOVES ACROSS THE AREA...SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO DEVELOP.
WITH MOST OF THE FORECAST AREA STILL AHEAD OF THE COLD
FRONT...TEMPERATURES IN THE CENTRAL AND EASTERN CWA WILL CLIMB INTO
THE MID 80S. THE DAY WILL AGAIN FEEL HUMID WITH DEWPOINTS
APPROACHING 70F.
.MQT...NONE.
JHB
FXUS63 KAPX 271522 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1040 AM EDT SUN JUN 27 1999
TRICKY FCST THIS AFTERNOON ON A NUMBER OF FRONTS. CLOUDS/TEMPS/PCPN
ALL ARE IN DOUBT TO SOME DEGREE.
DIFFICULT TO FIND A MODEL TO PUT MUCH CREDENCE IN THIS MRNG. MESO
LOW LOCATED OVER WRN LK ERIE WAS POORLY HANDLED BY ALL THE MESO
MODELS EXCEPT THE RUC. HOWEVER...THE RUC SOLN OF S/WAVE ENERGY MOVG
BOTH NORTH AND SOUTH OF THE CWA IS UNACCEPTABLE...WITH THE MESOETA
SOLN PREFERRED...DRIFTING THE BULK OF S/WAVE ENERGY ACROSS NRN IN
TOWARD FAR NW OH THIS AFTERNOON.
12Z DTX SNDG NOT ESPECIALLY USEFUL AS IT WENT UP INTO A TSRA. NOT
REAL THRILLED WITH THE MODEL DERIVED SNDGS EITHER. THE MODELS
PREDICT WARMING THROUGH MOST OF THE ATMOSPHERIC COLUMN TDY...IN THE
FACE OF ALMOST NIL WAA DUE TO ALMOST NIL WIND ALOFT...AND DEEP
(ALTHOUGH FAIRLY WEAK) UVV. ONE WOULD THINK...IF DEEP UPWARD MOTION
WAS TO OCCUR ALL DAY...LAPSE RATES WUD STEEPEN. MODELS DO NOT CONCUR.
SO I WL CHUCK THE MODELS ASIDE AND VENTURE OUT ON MY OWN. VSBL SAT
IMAGERY SHOWED MOSTLY CDY CONDS ACROSS THE CWA. THIN SPOTS ACROSS
TTF/ADG AREAS HAVE ALREADY SEEN QUITE A FEW CU DEVELOP. SAME GOES
FOR THE WRN PART OF THE STATE. THIS SHUD BE THE TREND ALL DAY...SO
MOSTLY CLOUDY WL BE FINE. WL ADJUST TEMPS DOWN A BIT GIVEN THAT
PERIODS OF SUNSHINE WL BE LIMITED IN SPACE AND TIME.
NONETHELESS...TEMPS WL STILL MAKE 80-85 TDY...AND THAT WL BE ENUF TO
REFIRE CONVECTION. LOTS AND LOTS OF BOUNDARIES IN THE AREA WL AID
THIS REDEVELOPMENT. SO SCATTERED POPS THRU MID-AFTERNOON TO COVER
STRAY SHRA...THEN LIKELY TSRA/SHRA LATE THIS AFTERNOON.
DIFFICULT TO ASCERTAIN INSTAB AVBL TDY GIVEN PROBLEMS WITH MODELS
AND 12Z DTX SNDG. BEST GUESS WUD INDICATE ABOUT 2000 J/KG AVBL AT
MAX HEATING. WITH ALMOST NO WIND FIELD TO SPEAK OF...A VERY HIGH
FREEZING LEVEL...AND LIMITED POTL FOR WATER LOADING DUE TO MOIST
AIRMASS..SVR POTL LOOKS VERY SMALL. HVY RAIN WL AGAIN BE THE BIGGEST
THREAT. COUNTIES THAT SAW THE HEAVIEST RAIN THIS MRNG WL BE CLOSELY
WATCHED (THAT WUD BE OAKLAND/WAYNE/SHIAWASSEE/SAGINAW).
THANKS FOR COORD GRR.
.DTX...NONE.
ZOLTOWSKI
FXUS63 KMQT 270826 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
300 AM EDT SUN JUN 27 1999
CHALLENGE TODAY IS POPS WITH ASSOCIATED COLD FROPA...
500MB FLOW CHARACTERIZED BY RIDGE OVER E CONUS AND TROF OVR GREAT
BASIN. COLD FRONT EXTDS S TO NW WI-SE MN FROM 1003MB SFC LO OVR S
ONTARIO AT 06Z. IR IMAGERY/88D SHOW CONVECTION ASSOC WITH FRONT
CONTINUING TO DIMINISH AT 06Z WITH WARMING CLOUD TOPS. ANOTHER AREA
OF SHRA/TSRA CONTINUES TO MOVE NE ACROSS WEST CENTRAL LOWER MI AND
LK MICHIGAN...WITH W EDGE OF SHIELD CLIPPING NEAR LK MI NEAR SHORE.
THIS AREA OF PRECIP APPEARS TO BE SUPPORTED BY SHRTWV ENERGY OVR S
LK MI...AND UPR LVL DIV IN RRQ OF JET STREAK OVR ONTARIO.
COLD FRONT PROGGED TO CROSS CWA FROM W TO E TODAY. GIVEN TIMING OF
PASSAGE...BEST OPPORTUNITY FOR SHRA/TSRA WILL BE OVR E CWA. RUCS
PRS/WND FIELDS DEPICT FRONT FROM MUNISING-IMT BY 18Z WITH BEST LOW
LEVEL MOISTURE POOLED E OF FRONT WITH DEWPOINTS IN UPR 60S OVR SE
CWA. ETA/RUC ALSO SHOWING 850 THETA-E RIDGE NOSING INTO
MNM-ESC...INCREASING SFC CONV AND BNDRY LYR LI'S IN -3 TO -5C. ETA'S
POS BOUY ENERGY'S OF 1600J/KG BETWEEN 18-21Z. SOLAR HEATING ONLY TO
BE LIMITED MARGINALLY BY HI CLOUDS. WBZ PROGGED TO BE ABOUT 9K-10K
FT BY ETA...SUGGESTING HAIL A THREAT WITH ANY TSRA THAT DO DEVELOP.
JET DYNAMICS ALSO COME INTO PLAY AS 100KT JET STREAK POSTIONS E CWA
IN RRQ BY 21Z. GIVEN LOCATION OF PARAMETERS HIGHEST THREAT FOR
STRONG/POSSIBLY SVR TSRA WILL BE MNM-ESC.
COLD FRONT EXITS CWA BY 00Z MONDAY AS NEXT SHORTWV EJECTS FROM
ROCKIES AND APPROACHES CWA DURING MONDAY. MODELS CONTINUE IN
DISAGREEMENT WITH EVOLUTION OF SHORTWAVE ENERGY AND ASSOC SFC
REFLECTION WITH AVN/NGM DEVELOPING EJECTING LO THAT RIDES NE ON OLD
FRONTAL BDRY...DEEPING AS IT MOVES THROUGH E LKS INTO CANADA. ETA
CONTINUES TO OFFER MUCH WEAKER SOLUTION...AND IS PREFERED BY NCEP.
GIVEN SUPPORT OF STONGER SOLN BY ECMWF...AM NOT WILLING TO TOTALLY
DISCARD AVN/NGM. WILL RETAIN SHRA ON MONDAY. WEAK RIDGING OVR CWA
TUESDAY...WITH NEXT SHORTWAVE IN PROGRESSIVE FLOW BRINGING NEXT
CHANCE OF SHRA/TSRA WITH RETURN FLOW OFF GULF BY LATE WEDESDAY/THURS.
.MQT..NONE.
WOLF
FXUS63 KGRR 270809 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1015 AM CDT SUN JUN 27 1999
HAVE UPDATED TO END PRECIPITATION IN ALL BUT S CENTRAL MN AND W
CENTRAL WI. 12Z CONSTANT PRESSURE ANALYSIS HAS DRY AIR PUSHING INTO
NRN AND W CENTRAL MN. LATEST RUC MODEL ALSO DRIES OUT WITH
ISENTROPIC LIFT WEAKENING AND NOT SATURATING. TEMPERATURES TRICKY
DUE TO LINGERING CLOUD COVER...BUT COLD ADVECTION SHOULD BE ENOUGH
TO KEEP COOLER HIGHS IN W CENTRAL.
.MSP...NONE.
SCOTT
FXUS63 KMPX 270847 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1001 AM EDT SUN JUN 27 1999
09Z RUC SHOWS ONE SHORT WAVE WEAKENING AS MOVES INTO THE CWA AND ANOTHER
ONE TO AFFECT OUR AREA LATER THIS AFTERNOON. FIRST WAVE OF SHOWERS
DISSIPATING AS THEY MOVE IN. WE CURRENTLY HAVE LIKELY POPS WITH TEMPS IN
THE UPPER 80S. THIS STILL LOOK OKAY. TEMPS ARE IN THE UPPER 70S EVEN
WITH CLOUDY SKIES.
NO CHANGES PLANNED.
.CAE...NONE.
LM
FXUS62 KCHS 271351 sc
AREA FORECAST DISCUSSION...CORRECTED TO ADD COORDINATION SECTION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
939 AM EDT SUN JUN 27 1999
EARLY VISIBILE IMAGES SHOW PARTLY CLOUDY SKIES IN EASTERN MOST
CWFA...BUT CLOUDY SKIES DOMINATING MOST OF THE REGION. VORTICITY
CENTER AND SHORTWAVE SHOW UP WELL ON WATER VAPOR LOOP CHARGING
STEADILY EASTBOUND TOWARD OUR REGION...AND RESPONSE TO LOW LVL VORT
APPEARS NICELY ON VISIBILE IMAGE IN MIDDLE TENNESSEE AND NORTHERN
ALABAMA. KGSP 88-D SHOWS FIRST ROUND OF CONVECTION ERODING AS IT
MOVES INTO UPSTATE SOUTH CAROLINA...BUT KFFC 88-D SHOWS LINE OF
CONVECTION MAKING STEADY PROGRESS INTO WESTERN GEORGIA. WOULD
EXPECT ADDITIONAL CONVECTION TO FIRE OVER OUR REGION THIS AFTERNOON
AS SHORTWAVE NEARS AND DAYTIME HEATING MAXIMIZES INSTABILITY. 09Z
RUC SUGSTS ONE FINAL SURGE OF MOISTR CONVERGENCE IN UPSTATE/SOUTHERN
NC THIS AFTN...AS DRIER AIR APPROACHES EAST GEORGIA IN ASSN WITH
SHORTWAVE. PLAN TO CONTINUE CURNT ADVERTISED HIGH POPS.
AREA SOUNDINGS REMAIN QUITE MOIST WITH PRECIPITABLE WATERS ON ORDER
OF 1.9 INCHES. UNLIKE THE PAST FEW DAYS...HOWEVER...ARE SOME FASTER
WINDS ALOFT...WHICH SHOULD PRECLUDE CELLS FROM LINGERING OVER ONE
AREA FOR TOO LONG...AS HAPPENED ON SATURDAY ACROSS NORTHEAST GEORGIA
AND PARTS OF WESTERN NORTH CAROLINA. ENTERTAINED THOUGHTS OF FLASH
FLOOD WATCH FOR NORTHEAST GEORGIA; ONE ROAD WAS UNDER WATER FOR A
BRIEF TIME ON SATURDAY JUST EAST OF CLARKESVILLE. FLASH FLOOD
GUIDANCE WILL NO DOUBT BE LOWER THAN THAT OF SATURDAY ACROSS THIS
REGION; TOCCOA CAME IN WITH 2.1 INCHES PAST 24-HRS...BUT EXPECT
CONVECTION TO MOVE RIGHT ON ALONG TODAY IN FASTER FLOW SO WILL HOLD
OFF ON FFA FOR NOW BUT MONITOR CLOSELY DURING THE DAY.
TEMPERATURES RUNNING WELL AHEAD OF YESTERDAY/S READINGS AT THIS SAME
TIME IN NORTH CAROLINA; CONCORD ALREAD 81 AND LINCONTON AT 79. MAY
OPEN UP RANGE OF TEMPERATURES IN NC ZONES BUT OTHERWISE DO NOT
ANTICIPATE MANY CHANGES IN THIS REGARD.
.GSP...NONE.
BURRUS
FXUS62 KGSP 271340 sc
SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
930 AM CDT SUN JUN 27 1999
QUICK LOOK AT MORNING ANALYSIS AND 12Z RUC INDICATE UPR RIDGE
DOMINATING TODAY. DRT CAPPED UNDER SUBSIDENT RIDGE. ACTIVE SEA
BREEZE INDICATED BY RUC CONVERGENCE WILL TRIGGER ISOLATED CONVECTION
IN SOUTHEASTERN ZONES. MAX TEMPS CENTRAL ZONES WILL STRUGGLE
AGAINST RESIDUAL MOISTURE...ALTHO A COUPLE MORE DAYS OF 15KT WINDS
WILL NULLIFY THIS CONSTRAINT. GOING FORECAST HAS THIS WELL IN HAND
AND NO UPDATE ANTICIPATED.
.SAT...NONE.
10/01
FXUS64 KHGX 271413 tx
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
308 PM MDT SUN JUN 27 1999
FAIRLY DECENT EAST-SOUTHEAST LOW LEVEL FLOW OVER THE PLAINS AT THIS
TIME....WITH PLENTY OF UPPER 50S DEW POINTS EVERYWHERE. LAPS DATA
SHOWING A STRONG LOW LEVEL THETA-E AXIS OVER US...WITH THE BEST
MOISTURE CONVERGENCE PILING UP ALONG THE FOOTHILLS AND FRONT RANGE.
RADAR SHOWING SOME A DECENT BOUNDARY NORTH-SOUTH ACROSS DOUGLAS
COUNTY AND AREA OBSERVATIONS ARE HINTING AT A DENVER CYCLONE SETTING
UP. SATELLITE PICTURES ARE SHOWING A BOUNDARY ACROSS THE NORTHEAST
CORNER OF THE PLAINS...AND SOMETHING ALONG THE CHEYENNE RIDGE...WITH
ONLY MINIMAL CUMULUS DEVELOPMENT AT THIS TIME OVER THE CWA. SOME
CONVECTION GOING NORTH OF THE BORDER IN WYOMING AND NEBRASKA...BUT
NONE YET HERE. TROUBLE IS...NOT ABLE TO WARM ENOUGH YET TO BREAK
THE INVERSIONS ABOVE US. LATEST ACARS SOUNDINGS STILL SHOWING
STRONG 700 MB CAP OVER THE AREA...AND A LITTLE ONE AT ABOUT 450 MB.
THE CAP WILL BE HARD TO GO AGAIN THIS AFTERNOON...BUT IF IT CAN
...LAPS SHOWING SOME 2000-4000 JOULES OF CAPE TO WORK WITH RIGHT
ALONG THE URBAN CORRIDOR AT THIS TIME. WATER VAPOR PICTURES STILL
SHOWING THE UPPER TROUGH AXIS WELL UPSTREAM...WITH THE RUC/MESOETA
GETTING THEIR Q-G ASCENT/THERMAL TROUGH INTO HERE AFTER 00Z. 80-100
KNOT JET NOW IN THE AREA AS EVIDENT BY PROFILERS AND RAWS MOUNTAIN
WIND SENSORS. THIS IS PROGGED TO CONTINUE OVERNIGHT. I STILL THINK
WE'LL GET THE STORMS...SOME SEVERE TOO.
FOR MONDAY THROUGH TUESDAY...FAIRLY STRONG WEST-NORTHWESTERLY FLOW
ALOFT IS PROGGED...WITH THE DIV-Q/POTENTIAL VORTICITY/UPPER WIND
GRIDS SHOWING SOME VERY WEAK SYNOPTIC SCALE LIFT FROM TIME TO TIME.
WATER VAPOR PICTURE PROGS WOULD BE NICE FOR LOCATING THESE
FEATURES. THE LOW LEVEL PRESSURE/WIND/MOISTURE GRIDS KEEP SHOWING
SURGES MOVING INTO THE PLAINS...WITH THE NEXT ONE IN HERE AROUND 18Z
MONDAY NOONTIME...THEN ANOTHER IN LATE TUESDAY AFTERNOON/EVENING.
THEY ALSO KEEP AN EASTERLY COMPONENT TO THE LOW LEVEL FLOW
THROUGHOUT THE PERIOD...AND DECENT THETA-E AXES AT MANY LEVELS.
CROSS SECTIONS SHOW GREAT POTENTIAL INSTABILITY AS WELL AND MODIFIED
FORECAST SOUNDING SHOWING 2000 J/KG PLUS CAPES FOR THE PLAINS BOTH
DAYS. THE WIND PROFILES SHOW BEST SHEAR FOR STORMS TUESDAY
AFTERNOON (SOUTHEAST SURFACE FLOW)...WITH MONDAY AFTERNOON IN THE
NORTHEAST LOW LEVEL FLOW. THE LAPSE RATES ARE VERY STEEP BELOW 500
MB BOTH AFTERNOONS...BUT SOME 500/400 MB CAPPING INDICATED IN THE
TEMPERATURE GRIDS OFF AND ON THROUGH THE NEXT TWO DAYS. WITH ALL
THE MOISTURE EXPECTED...EASTERLY FLOW...AND LATE EVENING MCS'S TO
CONTEND WITH...MORNING STRATUS IS A GOOD BET AS WELL. BASICALLY IT
WILL BE MORE OF THE SAME...WITH PLENTY OF ENERGY AVAILABLE FOR
SEVERE WEATHER BUT TRYING TO FIGURE OUT THE MID LEVEL CAP SITUATION
... THE LOW LEVEL STABILIZATION OR NOT...AND ANY HELP FROM A
SYNOPTIC SCALE LIFTING MECHANISM OR NOT. RIGHT NOW WILL GO WITH
SOME AFTERNOON/EVENING STORMS...MORE ON TUESDAY...AND MORNING
STRATUS. TEMPERATURES WILL BE AT OR BELOW THE SEASONAL NORMS FOR
THE NEXT TWO DAYS.
FOR THE EXTENDED PERIOD...THE LAST 4 OR 5 MRF RUNS HAVE ALL SHOWN A
DECENT UPPER TROUGH OVER COLORADO AROUND WEDNESDAY...HOWEVER THE
LATEST RUN (06/27 00Z) NOW JUST INDICATES PRETTY DECENT WEST-
NORTHWEST FLOW ALOFT...NO TROUGH ANYMORE? ANYWAY...THIS WEST-
NORTHWEST FLOW IS PROGGED THROUGH THE EXTENDED PERIOD WITH A COUPLE
OF SURGES OF UPSLOPE AT THE SURFACE. WITH THE NORTHWEST FLOW
USUALLY HAVING PLENTY OF SYNOPTIC SCALE ENERGY EMBEDDED IN IT...AND
THE GRIDS SHOWING SOME MOISTURE OVER THE EASTERN HALF...WILL KEEP
"CHANCE" IN ALL THREE DAYS. RJK
.DEN...NONE.
FXUS65 KGJT 272036 co
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL ...CORRECT TEMP CODING...
210 PM CDT SUN JUN 27 1999
IR SAT LOOP SHOWS MASSIVE MCS THAT DEVELOPED IN SW NE LAST NIGHT HAS
NOW DISSIPATED. THIS COMPLEX LEFT BEHIND SEVERAL CONVECTIVELY INDUCED
VORTS AND BOUNDARIES WITH CONVECTION FIRING UPON THESE FEATURES THIS
AFTERNOON. ONE VORT IN CRL IA FCST BEST BY ETA...ONE IN CRL MO (15Z RUC
PICKED THIS OUT) AND ONE IVOF MCI. NO MODELS YET CAUGHT ONTO THIS. NO
PCPN ATTM ACRS ILX CWA BUT ONLY A MATTER OF TIME BEFORE PCPN RETURNS TO
FCST AS SFC COLD FRONT MOVES TOWARD AND THRU IL OVR NEXT 30 HRS.
MAIN FCST CHALLENGE IS PCPN TRENDS.
KILX 88D SHOWING CONVECTION JUST WEST OF MISSISSIPPI RIVER AT 18Z...
THIS FIRING ON OUTFLOW BOUNDARY FM LAST NIGHT\S MCS. ANY EWRD PROGRESS
OF STORMS SHLD SEE DIMINISHING TRENDS AS THEY BUMP INTO WEAK RIDGING
OVR IL. THIS WL KEEP DRY FCST GOING TODAY. TONIGHT A DIFFERENT STORY AS
TODAY\S CONVECTIVELY INDUCED VORTS MOVE INTO IL. ETA FCSTS IA VORT TO
TRACK INTO NRN IL BETWEEN 00-06Z. ETA CONTINUES TO SHOW GREAT
CONSISTENCY RUN TO RUN AND WL BE FOLLOWED CLOSELY. NGM/AVN BOTH TRY TO
DEEPEN UPR TROF TOO MUCH INTO SRN RIDGE.
RUC SHOWING VORT ATTM IN CRL MO TRACKING MORE SE WITH MEAN FLOW AND
SHLD NOT AFFECT IL WX. HOWEVER...VORT NEAR KANSAS CITY WL FOLLOW MORE
E-ESE TRACK AND WL PROBABLY MOVE INTO SRN IL THIS EVE. ETA PICKED UP ON
THIS FEATURE ON YESTERDAY\S 12Z RUN.
WITH BEST DYNAMICS STAYING N AND S OF ILX CWA TONIGHT...BEST PCPN
CHANCES WL HOLD OFF UNTIL FROPA ON MON. WITH ACTIVE VORTS IN MO AND
IA...WL PUT HIGHEST POPS ACRS SERN AND NRN ILX CWA TONIGHT. 50 POPS
THERE WITH 40S ELSWHERE. ETA SHOWS FROPA AT ILX AROUND 18Z MON. TOO
CLOSE TO CALL ON TIMING WITH ENDING PCPN...SO WL GO LIKELY POPS TMRW CWA
WIDE AND TIME CLEARING NW-SE MON NIGHT. MUCH COOLER/LESS HUMID WX TO
FOLLOW TUE ON BACK-SIDE OF COLD FRONT.
MCS DEVELOPMENT LIKELY AGAIN TONIGHT...BUT FARTHER S AND E...IN KS.
MCV FM THIS FCST TO PUSH INTO SRN IL AND ENHANCE PCPN CHANCES AND HOLD
FRONT BACK MORE IN SRN IL. THERE4 WL INTRO HVY PCPN WORDING THERE.
WITH EXTENSIVE CLOUDCOVER AND HIGH DEWPOINTS FCST...WL GO WITH HIGHER
FWC TONIGHT...AND SIDE WITH MUCH COOLER FAN TMRW.
PRELIMINARY TEMPS/POPS
SPI TB 070/079 061/078 059 81462
PIA TB 069/077 059/075 057 81561
DEC TB 069/080 060/076 058 81462
CMI TB 069/080 061/075 059 81462
MTO TB 071/082 062/076 060 81573
LWV TB 072/083 064/078 061 81573
PLAHMER
EFFECTIVE AT 4 AM CDT JUL 7 1999...THIS PRODUCT WILL BE ISSUED UNDER
THE FOLLOWING HEADERS:
NOAA WEATHER WIRE: CHIAFDILX
FAMILY OF SERVICES: FXUS63 KILX (NO CHANGE FROM CURRENT)
FXUS63 KILX 271849 il
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
300 PM EST SUN JUN 27 1999
TIMING OF PCPN IS THE MAIN FORECAST PROBLEM AND WITH ONLY WEAK SFC
FEATURES TO KEY ON THIS WILL BE NO EASY TASK. 18Z SFC MAP SHOWED A
VERY MOIST AND UNSTABLE AMS ACROSS THE FORECAST REGION. A WEAK SFC
AND UPR TROUGH WAS OVER EASTERN INDIANA WITH A WEAK SFC RDG OVER IL.
FARTHER WEST THE REMAINS OF A LARGE MCS WAS OVER CENTRAL MO AND NE
KS. MODELS BRING THE WEAK SFC RDG ACROSS INDIANA TONIGHT. HOWEVER
THERE IS SOME HINT FROM NGM/AVN AND 18Z RUC THAT PCPN WEST OF THE MIS
RIVER COULD AFFECT SW PORTIONS OF OUR FORECAST AREA LATE TONIGHT.
THE ORIENTATION OF THICKNESS LINES AND A 35 KNOT 850 JET OVER MO
WOULD FAVOR ANY CONVECTION WEST OF THE MIS RIVER MOVG ESE TOWARDS THE
LOWER OH VLY.
MODELS BRING A S/W TROUGH ACROSS INDIANA ON MONDAY. I PREFER THE
SLOWER ETA/AVN WHICH BRINGS IT ACROSS INDIANA LATER DURING THE DAY.
THERE IS ALSO DIFFERENCES WITH THE STRENGTH OF A DVLPG SFC LOW WHICH
MOVS NE INTO THE EASTERN GREAT LAKES BY 48 HOURS. FOR THIS TIME OF
YEAR THE WEAKER ETA SOLUTION SEEMS MORE REASONABLE. AFTER THE LOW
MOVS INTO THE GREAT LAKES ALL MODELS PULL THE CD FNT SOUTH ACROSS THE
STATE.
OVERALL FWC TEMPS HAVE BEEN DOING PRETTY GOOD LATELY AND WILL GO
PRETTY CLOSE TO THEIR NUMBERS FOR TONIGHT AND MONDAY AND ALSO ON TUE.
FOR MONDAY NIGHT WILL GO SLIGHTLY COOLER BUT ONLY A COUPLE OF DEGREES
AS EVENING CONVECTION AND COOLER AIR MOVG IN MAY BRING TEMPS DOWN A
LITTLE MORE.
.IND...NONE.
HENDRICKSON
FXUS63 KIWX 271830 in
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
954 AM EST SUN JUN 27 1999
SVRL PROBLEMS TO DEAL WITH THIS PM INCLUDING LEFT OVR POP... TEMPS
AND CLDS. 14Z OBS AND 12Z RAOBS INDICATE DEEP LYR MOISTURE STILL IN
PLACE ACRS FA THIS AM. SW TROF BISECTING FA ATTM WITH MAIN AREA OF
SYNOPTIC FORCING SHIFTING INTO NW OHIO. SOME NEW SHRA DVLPMNT
BEGINNING TO TAKE PLACE ACRS BRANCH COUNTY AND BACK SW NR LAF.
WITH ALL LOW LVL MOISTURE IN PLACE WILL BE TOUGH TO GET MUCH SUN
GIVEN STEEPENING LOW LVL LAPSE RATES WITH DIURNAL HEATING TDA. VIS
SAT CONFIRMS THIS WITH ALOT OF CU FILLING IN BEHIND SW TROF BACK
INTO IL. WILL THEREFORE TRIM BACK ON MAX TEMPS AND TAKE MORE
PESSIMISTIC APPROACH TO CLD CVR THIS PM. POPS STILL LOOK GOOD IN
ABSENCE OF CLR CUT LOW LVL FOCUSING MECHANISM BUT MODIFIED 12Z
RAOBS AND 03Z/12Z ETA/RUC FCST SNDGS PUT CAPES TO 2K J/KG AND LI TO
-6 SO PLENTY OF INSTABILITY THIS PM TO REFIRE THINGS. WITH LWR
TROP FLOW SO WK WILL NEED TO WATCH FOR HVY RA THREAT AS SVR CHANCES
NIL.
.IWX...NONE
TEH
FXUS63 KIWX 270827 in
FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
300 PM CDT SUN JUN 27 1999
THE LATEST WATER VAPOR IMAGERY LOOP SHOWS DRIER AIR HAS PUSHED INTO
EXTREME WESTERN EDGE OF FORECAST AREA. THIS DRIER AIR IS SUPPRESSING
CONVECTIVE DEVELOPMENT IN WESTERN SECTIONS OF THE FA. THE RUC
FORECAST SOUNDINGS SHOW THIS DRY MID-LEVEL AIR PENETRATING ACROSS
THE FA BY TONIGHT...WHICH SHOULD CAUSE RAPID DIMINISHING OF
CONVECTIVE ACTIVITY THIS EVENING AFTER SUNSET WEST OF INTERSTATE 55
EXCEPT FOR EXTREME NORTHERN SECTIONS. THE MOST SIGNIFICANT CONVECTION THIS
AFTERNOON IS MAINLY EAST OF INTERSTATE 55 BUT EVEN THIS ACTIVITY
WILL TEND TO DISSIPATE AFTER SUNSET. HOWEVER...IN EXTREME NORTHERN
MISSISSIPPI...OUTFLOW FROM MCS THAT IS PUSHING SOUTHWARD TOWARD
MISSISSIPPI MAY HELP TO INITIATE ADDITIONAL CONVECTIVE ACTIVITY IN
EXTREME NORTHERN PARTS OF FA THIS EVENING. ON MONDAY...DRIER AIR AT MID
LEVELS WILL AFFECT ENTIRE FORECAST AREA. HOWEVER...LOW LEVEL
MOISTURE WILL REMAIN PLENTIFUL SO EXPECT ISOLATED TO WIDELY
SCATTERED POPS ACROSS FA. ON TUESDAY...NGM AND AVN BRING COLD FRONT
INTO NORTHERN MISSISSIPPI...BUT ETA KEEPS BOUNDARY NORTH OF THE MS
BORDER. I WILL GO WITH ETA FORECAST AND INCREASE POPS IN EXTREME
NORTHERN MS AHEAD OF FRONTAL BOUNDARY ON TUESDAY AFTERNOON.
ELSEWHERE IN THE FA...EXPECT POPS TO BE ISOLATED.
FOR TEMPS...EXPECT HIGH TEMPS TO BE SLIGHTLY ABOVE NGM MOS ON MONDAY
AND TUESDAY IN CENTRAL AND SOUTHERN AREAS. WITH PLENTIFUL SUNSHINE
EXPECTED ACROSS THE FA ON BOTH MONDAY AND TUESDAY TEMPS SHOULD WARM
INTO THE 90S...BUT WITH A GOOD PRESSURE GRADIENT BETWEEN HIGH
PRESSURE CENTER EAST OF FLORIDA COAST AND LOW PRESSURE IN SOUTHERN
PLAINS WILL CAUSE SURFACE WINDS TO BE STRONG ENOUGH TO MIX THE AIR
AND PREVENT TEMPERATURES FROM CLIMBING ABOVE THE LOWER 90S IN MOST
LOCATIONS. FOR LOW TEMPS...WILL STAY CLOSE TO NGM MOS.
IN THE EXTENDED...EXPECT FRONT ALONG NORTHERN MS BORDER TO MOVE BACK
NORTHWARD. THEREFORE...ENTIRE FORECAST AREA WILL CONTINUE TO BE IN
WARM UNSTABLE AIRMASS WITH LOW LEVEL SOUTHWESTERLY TO SOUTHERLY
FLOW. THEREFORE...EXPECT THE USUAL ISOLATED AFTERNOON AND EARLY
EVENING THUNDERSTORMS EACH DAY WEDNESDAY THROUGH FRIDAY WITH
SEASONAL HOT AND HUMID CONDITIONS AND ISOLATED THUNDERSTORMS.
QPF DISCUSSION: AIR MASS STILL MOIST WITH SCATTERED SHOWERS AND
THUNDERSTORMS FEEDING ACROSS THE EASTERN HALF OF THE STATE. THE
DRIER AIR FILTERING INTO THE WEST WILL KEEP CONVECTION MINIMAL
THROUGH THE EVENING HOURS IN THAT AREA. AT THIS TIME THE BEST CHANCE
FOR PRECIP WILL BE IN THE EAST AND SOUTH MAINLY DURING THE FIRST 6
HOURS. WILL GO WITH AMOUNTS OF 1/10 TO 1/4 INCH THERE AND LESSER
AMOUNTS ELSEWHERE.
.JAN...
MS...NONE.
LA...NONE.
AR...NONE.
15
FXUS74 KJAN 270856 ms
NORTHEAST MONTANA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
245 PM MDT SUN JUN 27 1999
SCT SHOWERS LINGERING OVER CENTRAL AND EASTERN PORTIONS OF GLASGOW
CWFA. LATEST MODEL RUNS INDICATE A COUPLE OF SHORTWAVES TO MOVE THRU
EASTERN PORTION OF MONTANA THRU FCST PERIOD. NONE OF THE MODELS
HANDLING THE TIMING OF THE SHWVS. RUC SEEMED TO DO BEST PICKING UP
ON VORT MAX OVER EASTERN MT THIS AM AND THE ASSOCIATED PRECIP GOING
ON ATTM. BROAD UPPER TROF TO LINGER OVER NEMONT THRU MONDAY
AFTERNOON WHEN UPPER PATTERN BECOMES MORE ZONAL. SUM RIDGING TO TAKE
PLACE OVER NEMONT MONDAY AS UPPER LOW SLIDES DOWN CANADIAN PAC COAST
BUT UPPER TROF RETURNS BY TUES AFTERNOON...NGM AND AVN HITTING
RIDGING THE HARDEST AND TRYING TO WARM NEMONT UP A TAD TOO MUCH.
MODEL QPF'S INDICATING PCPN THRU MUCH OF FCST PERIOD...AVN THE
DRIEST. NGM AND ETA MORE IN LINE AND DO EXPECT PCPN TO BE SCT THRU
MONDAY AFT. TEMPS OVERDONE ON FAN WITH AVN REALLY TRYING TO WARM
NEMONT UP ON MONDAY. MOS NUMBERS NOT TOO OUT OF WHACK EXCEPT FOR GGW
WHERE IT MAY BE TOO WARM. WILL KEEP POPS SCT THRU MONDAY AND BRING
POPS BACK IN TUESDAY AS NEXT TROF APPROACHES AREA.
EXTENDED...UNSETTLED PATTERN CONTINUES WITH NORTHWEST FLOW ALOFT AND
A SERIES OF SHORTWAVES MOVING THRU. COOLER THAN NORMAL TEMPS TO
CONTINUE. KPB
GGW 6323 046/072/049/070
GDV 6423 048/073/050/071
CCF
GGW WB 046/072 049/070 050 75632
FXUS65 KTFX 272047 mt
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
955 AM EDT SUN JUN 27 1999
ABUNDANT SUN ALLOWING MOST OF ILM CWA TO WARM QUICKLY THIS MORNING.
VIS IMAGERY SHOWS ENCROACHING CLOUDS FROM SW AND CU ALREADY
DEVELOPING. A PARTLY SUNNY FCST SHOULD WORK WELL FOR REMAINDER OF
THE DAY. 12Z CHS SOUNDING INDICATES SOME INSTABILITY ALREADY IN
PLACE...ESPECIALLY ALONG THE COAST. UNMODIFIED...THE SOUNDING YIELDS
A -4 LI...CAPE APPROACHING 1000 J/KG...AND A K-INDEX OF 35. MODIFIED
TO AN AFTN HIGH NEAR 90...THE LI DROPS TO -7 AND CAPE INCREASES TO
NEARLY 3000 J/KG. GIVEN THESE PARAMETERS...AT LEAST SCATTERED TSTMS
WOULD DEFINITELY BE SUPPORTED. LATEST RUC INDICATES MAIN H5 S/WV TO
STILL BE IN W TN AND GA THIS AFTN ALTHOUGH A WEAKER FORERUNNING
RIPPLE COULD ENTER THE WESTERN CWA BY LATE AFTN ALONG WITH AFTN MAX
TEMPS. AND AT LEAST SOME CONVECTION SHOULD FIRE ALONG SEA BREEZE-
TYPE BOUNDARY. SEE NO NEED TO LOWER POPS. AS A MATTER OF FACT...ANY
OTHER DAY THEY WOULD PROBABLY BE RAISED. BUT GIVEN THE OVER-
ADVERTISEMENT OF POPS LAST COUPLE OF DAYS I WON'T GO THAT ROUTE JUST
YET. AS FOR TEMPS...WITH EXPECTED CLOUD COVER...MORNING SOUNDINGS
AND LOCAL TEMP SCHEMES SEEM TO INDICATE THAT CURRENT FCST IS ON
TRACK. TO SUM IT UP...NO CHANGES PLANNED.
CWF: 12Z RUC SHOWS 20-25 KT WIND MAX AT 925 MB APPROACHING FROM THE
SW SO SHOULD SEE WINDS INCREASE THIS AFTN. CURRENT FCST SPEEDS LOOK
GOOD BUT WILL ADD AN INITIAL WIND SPEED FOR THE MEANTIME.
.ILM...NONE.
MORGAN
FXUS62 KILM 270655 nc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
928 AM CDT SUN JUN 27 1999
HAVE ALREADY UPDATED ALL ZONES TO REFLECT CURRENT WIND AND CLOUD
TRENDS ACROSS THE FA. INSOLATION IS RESULTING IN MIXING OF HIGH
MOMENTUM AIR JUST OFF THE SURFACE WITH 30 TO 40 KNOT LLJ PER AREA
PROFILERS/88D VAD WINDS. 12Z RUC IS INDICATING 20 TO 30 KNOTS AT
925 AND 850 MB ACROSS MUCH OF THE AREA THRU THIS AFTERNOON. SO BASED
ON CURRENT TRENDS..I SEE NO REASON WHY WINDS WILL NOT REMAIN AOA
CAUTION LEVELS OVER THE NRN TWO THIRDS OF THE FA TODAY. HOWEVER..
HIGHEST GUSTS SHUD BE FROM NOW THRU THE EARLY AFTERNOON WITH SOME
DECREASE IN SPEEDS THEREAFTER AS LLJ WEAKENS. MID LEVEL CLOUDS ARE
ALSO MOVING INTO THE FA IN ASSOCIATION WITH PLUME OF STEEPER MID
LEVEL LAPSE RATES AS SEEN ON 12 UA ANAL. NO CHANGES MADE TO TEMPS
ATTM.
MILLER
.OUN...
OK...CAUTION ON AREA LAKES NORTH OF A HOLLIS-FREDERICK-WEWOKA LINE.
TX...NONE.
FXUS64 KTSA 270908 ok
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
340 AM CDT SUN JUN 27 1999
LOUSY PERFORMANCE OF 00Z MODELS SPELLS JOB SECURITY TO ME. NONE OF
THE MDLS EXCEPT THE RUC BROUGHT THE SHOWERS AND TSTMS CURRENTLY IN
THE CWA EARLY ENOUGH. MDLS OF 24 HRS AGO DID A BETTER JOB THAN THIS
NEWEST GENERATION. DONT BELIEVE ME...EVEN THE 05Z HON LAMP MOS
COULDN'T FCST THE 05Z TSTMS THAT WERE IN THE SFC OBSERVATION.
OVERALL I DO NOT LIKE ANY OF THE MDL SOLNS AND THIS MORNINGS FCST
PKG WL UNFORTUNELY COMBINE ALL 3 SOLNS INTO THE FCST AND BROAD BRUSH
THE FCST. WHEN NECESSARY...FOLLOWED NGM SOLN SINCE YESTERDAY'S 00Z
RUN WAS CLOSEST IN PROGGING THIS EARLY MRNGS SYSTEM. MDLS HAVING A
DIFFICULT TIME IN TIMING AND LOCATION OF SHRTWVS TO MOVE ACROSS THE
NRN AND CNTRL PLAINS TDY THROUGH MON AS ROCKIES TROF IS SQUEEZED OUT
BY A BUILDING RIDGE IN WRN CONUS. ETA THE QUICKEST TO FILL IN TROF
THUS PROVIDES THE LEAST MID TO UPPER LVL SUPPORT FOR PCPN
DEVELOPMENT WHEN COMPARED TO THE NGM AND EVEN AVN. NGM/AVN ALSO
PLACE SFC LOW FURTHER N THAN ETA THEN SLOWLY MOVES SFC LOW AND
FRONTAL BOUNDARIES ENE THROUGH THE PKG. THESE DIFFERENCES ARE
SIGNIFICANT IN THAT BOTH THE NGM AND AVN INDICATE SIGNIFICANT LIFT
FOR PCPN DEVELOPMENT TNGT AND THE ETA PREFERS TO BRING SUBSIDENCE TO
THE AREA.
WHILE MOS/FAN PROVIDE SOME PRETTY HIGH POPS FOR TNGT AND MON IN MUCH
OF THE CWA...WITH PREVIOUS PKG HAVING 2ND AND 3RD PRDS DRY WL NEED
TO BE A LITTLE POLITICAL AND UNDERCUT GUIDANCE. HOPEFULLY 12Z MDL
RUNS WL PROVIDE A MORE CONSISTANT SOLNS BETWEEN THE MDLS RUNS AND
REALITY TO HELP WITH THE AFTN PKG. ALL I CAN SAY IS...GOOD LUCK...
OZFFSD ALREADY SENT BUT WL PROBABLY MAKE A FEW MORE CHANGES FOR
FINAL PRODUCT.
.FSD...NONE
BR
FXUS63 KUNR 270859 sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
951 AM EDT SUN JUN 27 1999
27/12Z SURFACE ANALYSIS INDICATES WEAK AMPLITUDE LOW PRESSURE TROUGH
EXTENDING FROM THE GREAT LAKES REGION...THROUGH CENTRAL TENNESSEE...
AND BACK TO THE SOUTHWEST. WESTERN LIMIT OF KMRX-88D REFLECTIVITIES
SHOWING NUMEROUS SHOWERS IN THE EASTERN CUMBERLAND PLATEAU...
EXTENDING INTO CENTRAL TENNESSEE FROM KHTX-88D. MODELS ARE CONSISTENT
IN CONTINUING A RATHER WEST PATTERN...WITH THE 12Z UPSTREAM MOISTURE
PROFILE FROM BNA/S SOUNDING MORE MOIST YET.
THE MAJOR FORECAST DILEMMA FOR THIS AFTERNOON IS PREDICTING HOW MUCH
RAIN WILL FALL? LOOKING AT THE LATEST MODEL DATA...IT APPEARS THAT
THE 09Z RUC HANDLED THE 12Z LOCAL SURFACE PRESSURE DISTRIBUTION
BEST. CONSIDERING THAT AN H5 S/W SYSTEM IS OVER THE SURFACE LOW
(SIMILARLY FEATURED IN THE 03Z MESOETA) WITH UVV/S IN THE MESOETA...
THE POTENTIAL FOR LOCALLY HEAVY RAIN WILL CONTINUE THIS AFTERNOON...
UNTIL THE SYSTEM SHIFTS EAST OF SOME WESTERN CWA LOCATIONS. MAY
TWEAK TEMPERATURES BASED ON RECENT TRENDS.
DM
FXUS74 KMEG 270736 tn