SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
225 AM MST FRI JUL 16 1999
SYNOPSIS...DRIER AIR WILL SLOWLY FEED IN FROM THE WEST THIS WEEKEND.
HOWEVER...AN UPPER LEVEL DISTURBANCE SOUTHWEST OF SAN DIEGO WILL
MOVE ACROSS ARIZONA THIS AFTERNOON AND MAY ONCE AGAIN IGNITE
THUNDERSTORMS WITH HEAVY DOWNPOURS. ONCE THE DISTURBANCE MOVES EAST
ON SATURDAY...THUNDERSTORM ACTIVITY WILL BECOME MORE ISOLATED. A
SLIGHTLY WETTER MONSOON PATTERN WILL REDEVELOP EARLY NEXT WEEK...
ALTHOUGH IT SHOULD NOT BE AS ACTIVE AS THE PAST TWO WEEKS.
DISCUSSION...IT'S NEAT TO SEE ALMOST EVERY RIVERBED IN TUCSON FULL
OF WATER, BUT THIS IS GETTING A LITTLE OLD. WE'VE BEEN VERY LUCKY
NOT TO HAVE FATALITIES AFTER THE DEGREE OF FLASH FLOODING WE'VE SEEN
THIS WEEK. DRY AIR DID WORK INTO THE MID LEVELS OVER SOUTH CENTRAL
AZ LAST EVENING, BUT NOW MOISTURE IS SPREADING BACK WESTWARD WITH
YUMA'S DEWPOINT UP 11F IN THE PAST HOUR. THE SOMEWHAT DRIER AIR MADE
LITTLE DIFFERENCE LATE YESTERDAY, ANYWAY, AS VERY WET STORMS FIRED
OVER THE WESTERN DESERTS. THAT PRETTY MUCH TELLS THE STORY: WE NEED
THE LOW LEVELS TO DRY OUT A LOT MORE BEFORE WE GET OUT OF THIS.
UNFORTUNATELY THERE'S ANOTHER MATCH TO THROW ON THE POWERKEG, THIS
TIME IN THE FORM OF A SUBTROPICAL SHORT WAVE APPROACHING THE BAJA
COAST. MODELS HAVE COMPLETELY MISSED THIS IMPORTANT FEATURE.
DIFFLUENCE AHEAD OF ANOTHER WEAK SHORT WAVE LIFTING INTO UT TOUCHED
OFF STORMS IN NW AZ OVERNIGHT. THE SOUTHERN WAVE LOOKS MORE POTENT
AND IS INDUCING A FAIR AMOUNT OF DIFFLUENCE OVER THE NORTHERN GULF.
I'M ALSO NERVOUS ABOUT THE RUC'S IDEA OF HAVING NORTH AZ IN THE
RIGHT-REAR QUAD OF A 60KT UPPER LEVEL JETLET. WITH PRECIP WATERS
STILL IN THE 1.5+" RANGE AND A WARM-CORE VORT HEADING THIS WAY, IT
LOOKS LIKE SOMEONE'S GOING TO GET DUMPED ON AGAIN PER NCEP QPFERD
DISCUSSION. BEST THREAT IS S AND E OF TUCSON WHERE UPPER DIVERGENCE
SHOULD BE MAXIMIZED AND MOISTURE WILL BE DEEPEST, BUT SINCE TUCSON
IS SO SATURATED, WE'LL ADD HEIGHTENED WORDING HERE AS WELL. WE'LL
ALSO RAISE POPS 20-30 PERCENT ACROSS THE BOARD.
WE'VE BEEN SAYING FOR DAYS NOW THAT DRYING IS COMING. THIS TIME,
THOUGH, IT LOOKS A A LITTLE MORE CERTAIN AS THE VARIOUS VORT MAXES
LIFT OUT AND INDUCE STRONGER, DRIER FLOW FROM THE WEST. IN THAT
REGARD, PREVIOUS FORECAST LOOKS FINE. MAY TRY TO DOWNPLAY ACTIVITY
ON SUNDAY BEFORE WEAK 500MB ANTICYCLONIC CIRCULATION DEVELOPS TO OUR
EAST AND RATCHETS UP ACTIVITY A BIT. PYTLAK
.TWC...NONE.
az
SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO
249 PM MDT FRI JUL 16 1999
TNGT/SAT: 19Z/16 SURFACE ANALYSIS HAD SHALLOW FRONTAL BOUNDARY FROM
KGCK-KSPD-KCOS-KCAG WITH "TRUE" COLD FRONT ACROSS THE DAKOTAS
THROUGH SOUTHERN WY INTO ID. KPUB 88D VAD WIND PROFILE SHOWING
ABOUT 8000 KT DEEP NORTHEAST-EAST FLOW. TWO MAIN CONCERNS TONIGHT
WILL BE MINOR SHORTWAVE PRESENTLY MOVING THROUGH WESTERN CO AND
UPSLOPE THREAT ACROSS SOUTHEASTERN CO MOUNTAINS AND ADJACENT
PLAINS. LATEST RUC/ETA HAVING A TOUGH TIME HANDLING WESTERN CO
SHORTWAVE BY TAKING IT TOO FAR NORTH AND WEST. CURRENT MANUAL
PROJECTION TAKE IT THROUGH CENTRAL AND EASTERN CO TONIGHT. LATEST
REGIONAL 88D/LIGHTNING DETECTION IMAGERY SHOWED WIDELY
SCATTERED/SCATTERED SHRA/TSRA BREAKING OUT IN THE CENTRAL AND
SOUTHEAST MOUNTAINS. GREATEST COVERAGE...SO FAR...IS IN UPPER
HUERFANO AND UPPER PURGATOIRE RIVER BASINS(74/75). MOISTURE
CERTAINLY NOT A PROBLEM. SURFACE DEW POINTS HAVE CLIMBED INTO THE
MID 50S/MID 60S ALONG AND EAST OF I-25 THIS AFTERNOON. WITH
COMBINATION OF MID-LEVEL SHORTWAVE AND EVENING UPSLOPE EASTERLY...
PLAN TO CARRY "LIKELY" WORDING FOR SANGRE DE CRISTO/WET MOUNTAINS
INCLUDING ZONES 74/75 TONIGHT. WILL GO WITH WIDELY SCATTERED/
SCATTERED COVERAGE IN THE PLAINS. WILL NOT CARRY A "TIMER" ON
PRECIPITATION WORDING FROM SOUTHEAST MOUNTAINS INTO THE PLAINS.
SHRA/TSRA MAY HANG ON A LITTLE LONGER WITH EXPECTED SHORTWAVE...
ALBEIT WEAK...MIGRATING THROUGH CWA. IN THE SOUTHWEST MOUNTAINS...
UPPER AR RIVER VALLEY...AND SAN LUIS VALLEY...SHRA/TSRA SHOULD BE OF
DIURNAL CHARACTERISTICS. WOULDN'T BE SUPRISED TO SEE STRATUS
POSSIBLY FORM IN THE PLAINS TONIGHT. NOT EXPECTED SIGNIFICANT
WIDESPREAD FOG...SO WILL NOT MENTION. LOWER TROP FLOW EXPECTED TO
GO MORE SOUTHERLY ON SAT WITH PLENTY OF RELATIVELY DEEP MOISTURE IN
PLACE. 500MB HEIGHTS START TO RISE WITH THE POTENTIAL FOR LOW LEVEL
SOUTHEASTERLY UPSLOPE FLOW DRIVEN SHRA/TSRA. PLAN TO MAINTAIN LOW
"CHANCE" POPS AND WORDING IN CURRENT ZFP. DAY 2 QPF HAS .25-.50"
PRECIPITATION DRAWN GENERALLY ALONG THE EASTERN MOUNTAINS.
SAT NGT/SUN: 500MB HEIGHT EXPECTED TO CONTINUE RISING AS A SERIES OF
MID-LEVEL SHORTWAVES EJECT ACROSS PACIFIC NORTHWEST FROM DEEPENING
LONGWAVE ALONG WEST COAST. SHRA/TSRA THREAT WILL LIKELY BE LESS AND
LESS WITH THE QUALITY OF DEPTH OF MOISTURE DECREASING AND MID-LEVEL
TEMPERATURES ON THE RISE. SHOULD SEE MORE OF A DIURNAL WIDELY
SCATTERED/SCATTERED SHRA/TSRA ACTIVITY ON SUN. SURFACE TEMPERATURES
TO INCREASE BACK INTO SUMMERTIME READINGS.
EXTENDED(MON-WED): LONGWAVE TROUGH WILL CONTINUE TO DEEPEN ALONG THE
WEST COAST ON MON WITH ANTICYCLONE TAKING SHAPE IN THE HEARTLAND OF
U.S. STILL SUFFICIENT AMOUNT OF MOISTURE TO GENERATE MAINLY
AFTERNOON AND EVENING SHRA/TSRA...ESPECIALLY IN MOUNTAINS. PLAN TO
LEAVE GENERIC "CHANCE" WORDING IN FOR MON. MRF CONTINUES TO HAVE
GOOD RUN-TO-RUN CONTINUITY ON BUILDING LARGE UPPER ANTICYCLONE INTO
CO/KS ON TUE-WED. 700MB TEMPERATURES STILL PROGD TO BE +16-20 C.
MRF IN PAST CASE SEEM TO BE OVERDONE ON THE 700-300MB MEAN RH AND
MAY BE CONTINUING THIS PRACTICE. BELOW 500MB...MEAN RH EXPECTED TO
RANGE FROM 10-20%. FEEL THREAT IS SO LOW ITS TOO EARLY TO MENTION AND
WILL WAIT UNTIL TUE-WED FORECAST GETS INTO THE SHORT RANGE TO FINE
TUNE. STILL COULDN'T RULE OUT AN ISOLATED TSRA IN MOUNTAINS...BUT TOO
FAR TO MENTION. MAIN WEATHER FEATURE TUE-WED SHOULD BE SUMMERTIME
HEAT AND A RETURN TO NEAR 100 DEG READINGS IN FAVORED AREAS
THROUGHOUT THE PLAINS.
.PUB...NONE.
METZE
FXUS65 KGJT 161831 co
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1005 AM EDT FRI JUL 16 1999
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS NOTED MORE THAN
15 MI OFFSHORE SHOULD GRADUALLY WEAKEN NEXT 6 HRS. MODIFIED SOUNDING
NUMBERS...LI OF -7...CAPE 3000 J/KG. GIVEN RATHER ACTIVE AREA OF
CONVECTION OFFSHORE LEADS ME TO INCREASE POPS FOR TODAY. IN
ADDITION...SFC ANALYSIS SHOWS A VERY WEAK LOW LEVEL CONVERGENT AREA
OVER N FL. RUC MODEL SEEMS TO HANDLE THIS FEATURE WELL AT THIS TIME
AND WEAKENS IT BY TONIGHT. HOWEVER...MESO-ETA KEEPS THIS FEATURE
PRESENT THROUGH 00Z. IN ANY CASE...WITH THIS WEAK FEATURE...AND E
COAST SEA BREEZE AND SOUNDING PARAMETERS...PREFER 10 PERCENT POP
INCREASE ACROSS FL CWA. REMAINDER OF FORECAST LOOKS GOOD.
ARS
FXUS62 KTAE 161351 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
215 PM CDT FRI JUL 16 1999
BROAD RIDGE OVER ERN AND SRN U.S. IN PLACE ALOFT WHILE ACTIVE JET
STREAM REMAINS OVER THE NRN U.S. WVAPOR SHOWS SOME MID/HIGH MSTR
OVER LOWER OHIO/MID MISSISSIPPI VALLEY REGIONS...AND ALSO SEEN ON
H7 ANALYSIS. IN SHORT TERM...WIDELY SCT SHRA/TSRA DEVELOPING ACROSS
PTNS OF THE FA. LAPS AND RUC SOUNDING FCSTS SHOW NO CAP THIS AFTN
WITH K-INDICES OVER 20...CAPES 2000-3000 J/KG. ALSO SEEN IS A WEAK
H7 SHEAR ZONE OVER THE REGION. EXPECT THIS ACTIVITY WILL DIMINISH
QUICKLY WITH LOSS OF HEATING. TONIGHT SHOULD BE CLEAR TO PARTLY
CLOUDY. PATCHY FOG CERTAINLY POSSIBLE...BUT WILL NOT MENTION AS MOST
AREAS WILL BE ABOVE 1 MILE MOST OF THE NIGHT.
IN TERMS OF THE MODELS...ETA AND NGM ON SAME TRACK...WITH THE AVN
IN DISAGREEMENT...ESPECIALLY WITH SPEED OF WEEKEND SYSTEM. WILL GO
WITH THE ETA/NGM. SATURDAY SHOULD BE HUMID BUT DRY FOR THE MOST
PART. MID-LVL DRYING REFLECTED IN LOWERING K-INDICES AND NIL UPPER
SUPPORT WILL CAP US OFF AHEAD OF FRONT WHICH WILL SETTLE SLOWLY
SOUTH ACROSS NORTHERN MISSOURI AND CENTRAL ILLINOIS BY SUNDAY
MORNING. MAY BE SOME DEBRIS CLOUDS THAT DRIFT SOUTH BY AFTERNOON
THUS WE WILL GO PARTLY SUNNY. GUIDANCE APPEARS REASONABLE. WILL
INTRODUCE A CHC OF SHRA/TSRA LATE SATURDAY NIGHT FOR NORTHERN AND
NORTHEAST AREAS. H8/H3 THICKNESS PROGS SUGGEST WHAT CONVECTION THAT
MAY BE ASSOC WITH FRONT TO OUR NORTH MIGHT START TO DRIFT SE...WHILE
BEING AIDED BY S/WV FCST TO MOVE TOWARD THE GREAT LAKES AND OHIO
VALLEY. AS FRONT GETS SLIGHTLY CLOSER ON SUNDAY...HIGHER MSTR
CONTENT IN GREATER DEPTH EXPECTED WHILE REMAINING RATHER UNSTABLE.
WILL INTRODUCE LOW POP FOR MOST AREAS ON SUNDAY. IN THE
EXTENDED...WILL CONTINUE WITH CHC FOR SHRA/TSRA AND TREND WORDING
TOWARD AFTERNOON. MRF MAY BE TOO AGGRESSIVE WITH MSTR...BUT DO
EXPECT UPPER HIGH TO RETREAT ON WESTWARD...WITH LAYER MEAN RH
REMAINING SOMEWHAT HIGH. ALSO FRONTAL BOUNDARY SHOULD SET UP INVOF
NORTHERN SECTIONS OF OUR CWFA.
.PAH...NONE.
NOLES
FXUS63 KPAH 161915 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1020 PM EDT FRI JUL 16 1999
A SLOW MOVING FNT XTNDS FROM SSM ACRS NRN LK MICHIGAN TO MKE AND ON
TO ERN IA. THIS FNT CONT TO MOV SE INTO LOWER MI. -RA AND -TSRA
ASSOC WITH OVRRNG OF THIS FNT. DWPNTS REMAIN HI IN THE 60S ACRS
THE FA. SAT IR SHOW SOME CLRG OVR MN AND NRN WI ATTM THIS IS ASSOC
WITH A THERMAL RIDGE NW OF LAKE SUPERIOR.
THE RIDGE IS MOVG E AT 10KTS AND HAD REACHED WRN UP BY 02Z AND WILL
WORK ITS WAY ACRS FA TNGT. SATURATED SOIL WILL HELP KEEP DWPNTS UP
TNGT. WITH SOME CLRG TNGT...LGT WNDS...AND HI DWPNTS...XPCT TO SEE
FOG FORMING ARND THE CNTRL AND ERN PART OF FA TNGT. ANOTHER SHRTWV
MOVG E OUT OF IA WILL PRODUCE A FEW SHOWERS OVR SRN AND ERN UP UNTIL
06Z. BY SR...BOTH ETA AND RUC SHOW THE THERMAL RIDGE SE OF FA AND
XPCT TO SEE SHRA OUT OF THE FA BY SR. THE SHRTWV WILL BE OVR NRN
LAKE MICHIGAN BY SR...SO EXPECT A FEW CLDS OVR SRN AND ERN COUNTIES
OF FA TNGT.
WITH DRYER AIR AND MORE STABILITY ACRS AREA ON SAT...XPCT PARTY
SUNNY SKIES.
.MQT...NONE.
DLG
FXUS63 KAPX 170357 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1115 AM EDT FRI JUL 16 1999
14Z SURFACE ANALYSIS SHOWS A SURFACE LOW LOCATED NORTH OF LAKE
SUPERIOR WITH COLD FRONT EXTENDING SW INTO IA. A STRENGTHENING 300MB
JET STREAK WILL PUSH UPPER LEVEL SUPPORT FOR THE LOW ALONG
QUICKLY...BUT WAVE THAT DEVELOPED ALONG THE COLD FRONT WILL CAUSE IT
TO BE SLOWER TO MOVE THROUGH THE AREA.
SURFACE DEWPOINTS IN THE UPPER 60S/LOWER 70S WILL MAKE FOR A STICKY
AND UNSTABLE DAY TODAY. 12Z OBSERVED SOUNDING FROM GRB HAD OVER 2000
J/KG CAPE. 03Z MESOETA BRINGS CAPES UP TO 3000 J/KG INTO MENOMINEE
COUNTY BY 00Z SATURDAY. 12Z RUC BRING BOUNDARY LAYER LIS APPROACHING
-5C TO THE WISCONSIN BORDER BY 00Z.
GREATEST FORCING ASSOCIATED WITH THE COLD FRONT WONT REACH THE AREA
UNTIL TONIGHT. BUT WITH DECENT HEATING...SHOWERS AND THUNDERSTORMS
WILL CONTINUE TO FIRE IN THE UNSTABLE AIR AHEAD OF THE FRONT. BIG
CONCERN IS FOR RAINFALL TONIGHT WITH FRONTAL PASSAGE. ONE HOUR FLASH
FLOOD GUIDANCE FOR THE SOUTHERN COUNTIES THAT WERE DRENCHED EARLIER IN
THE WEEK IS BELOW AN INCH... 0.8" FOR IRON AND 0.9" FOR DICKINSON
AND MENOMINEE.
SLIGHT ADJUSTMENTS TO TEMPS ARE NECESSARY...ALSO WITH CLOUD COVER.
WIND FORECAST LOOKS ON TRACK.
.MQT...FLASH FLOOD WATCH TONIGHT FOR MIZ010>012.
JHB
FXUS63 KDTX 161453 mi
AREA FORECAST DISCUSSION ... CORRECTED WARNING SECTION
NATIONAL WEATHER SERVICE MARQUETTE MI
425 AM EDT FRI JUL 16 1999
MAIN FOCUS FOR TDY IS THE COVERAGE AND TIMING OF PCPN W/ THE SYSTEM
MOVG THRU THE CNTRL U.S. ATTM.
RGNL RADAR/SAT PICS SHOW THE LINE TO XTND FM SRN ONT TO BRD TO
FSD...ROUGHLY SPEAKING THT IS. SINCE IT DVLPD...PCPN HAS BEEN LINING
UP VRY WELL W/ THE H85 THTE AXIS. LATEST RUC IS CONSISTENT W/ THE
00Z ETA IN BRINGING THAT AXIS TO FAR WRN U.P. ARND 12Z.
HOWEVER...WHAT IS A FAIRLY SOLID BAND OF HIGH THTE ATTM IS PROGGED
TO TO SORT OF SHEAR APART AS THE NRN PIECE OF ENERGY RACES THRU
CANADA TDY...PUSHING NRN PORTION OF FNT RIGHT ALG. A SECOND S/WV
...SEEN ON THE PROFILER DATA/EVE PLOTS IS HANGING BACK OVR ERN
NEBRASKA. ETA (AND TO LESSER EXTENT THE NGM) PICK UP ON THIS QUITE
NICELY. NGM FADES IT OUT SOMEWHAT...BUT ETA HOLDS ONTO IT AS IT
SLOWLY LIFTS TWD THE GREAT LAKES RGN.
INITIALLY PREFERED THE ETA SOLN FOR IT/S CONSISTENCY OVR TIME...BUT
THE NGM SHOWS STRONG FEATURES AS WELL (INCLUDING FVRBL JET DYNAMICS).
UNSETTLED WX ACRS THE FA TDY AND TNT WL POSE A PROBLEM ACRS THE
SOUTHWEST. PW VALUE ARE PROGGED TO BE VERY HIGH PHPS NEARLY AS HIGH
AS TWO INCHES...AND POSSIBILTIY OF TRAINING ECHOS EXISTS.
THUS...CONSIDERING THE PCPN THAT FELL ERLIER THIS WEEK OVR DICKINSON
...IRON AND THE LOW FFG VALUES FM DICKINSON TO MENOMINEE WL GO W/ A
FFA FOR THESE THREE COUNTIES AND STRESS THE SRN PORTIONS. FURTHER
EAST...CHCS OF PCPN BTR TNT. PER COORD W/ APX WL BUMP POPS IN ERN
CNTYS INTO LOW LIKELY CATEGORY.
ONCE THE FNT PASSES...DRIER...COLR AIR WL QCKLY ARRIVE. OTHR THAN A
LINGERING MORG SHRW IN THE FAR EAST LUKG FOR A RAINFREE...SUNNIER
DAY.
STEAMY CONDITIONS TO CONT THRU TDY W/ DWPTS GNRLY FROM THE MID 60S
TO MID 70S. CRNTLY FCST HIGHS ARE GNRLY FINE. LOWS FOR TNT NEED A
BOOST IN THE ERN SXNS. TEMPS TMRW SHD SHOW A PRETTY GOOD GRADIENT
FROM WEST TO EAST. H85 TEMPS SHOW A STG GRADIENT ACRS THE FA BY LATE
IN THE DAY SUNDAY. HELPING COLR TEMPS ALONG WL BE WNDS OFF LAKE
SUPER.
RMDR OF FCST UNCHANGED. NEW ECMWF SEEMS TO HAVE FLOPPED BACK
SLIGHTLY W/ IT/S SUNDAY SOLN FROM YESTERDAY... BUT 72 HR AVN DOES
SHOW AN AREA OF Q-VEC CONVERGENCE.
.MQT...FLASH FLOOD WATCH TONIGHT FOR MIZ010>012.
DESROSIERS
mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1115 AM CDT FRI JUL 16 1999
COLD FRONT CURRENTLY MOVING THROUGH NORTHWEST WISCONSIN. SHOWERS
ALONG THIS LINE AND WITH UPPER LVL SHORTWAVE...BOTH OF WHICH
CONTINUED TO WEAKEN. MSAS STILL SHOWING LI'S TO -5 AHEAD OF FRONT...
AND BOTH RUC AND ETA INDICATING CONDITIONS TO REMAIN SOMEWHAT
UNSTABLE THERE. HOWEVER BEST LIFT AND INSTABILITY WILL BE SOUTH OF
WISCONSIN CWA. ADDITIONAL LIFT FROM IOWA VORT LOOKS LIKE IT WILL ALSO
PASS TO THE SOUTH AS WELL. SO WILL KEEP THE MENTION OF THUNDERSTORMS
ALONG AND AHEAD OF FRONT...BUT AM NOT CONCERNED ABOUT SEVERE WEATHER
FOR ONCE.
FURTHER WEST...ANOTHER TROUGH PUSHING INTO WESTERN MINNESOTA WITH
MUCH DRIER AIR BEHIND IT. THIS WILL BRING INCREASING SUNSHINE TO
MUCH OF NORTHEAST MINNESOTA. HOWEVER...VORT SCOOTING ACROSS SOUTHERN
MANITOBA TO BRING MORE CLOUDS AND PERHAPS A FEW SHOWERS TO PORTIONS
OF NORTH CENTRAL MINNESOTA THIS AFTERNOON. CONDITIONS SHOULD REMAIN
STABLE ENOUGH TO PREVENT THUNDERSTORM DEVELOPMENT HERE.
PREVIOUS FCST TEMPS STILL LOOKING GOOD. WESTERLY WINDS WILL CAUSE
COMPRESSIONAL WARMING ALONG NORTH SHORE TO SUW.
.DLH...NONE.
TAP
FXUS63 KMPX 161601 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1100 AM CDT FRI JUL 16 1999
RAINFALL IN NWRN IA ASSOCIATED WITH SLOW MOVG NEDDY EDDY IN FAR
WESTERN IA. SLOW MOVING FRONT FROM WESTERN TIP OF LAKE SUPERIOR TO
NWRN IA. FRONT IS ALMOST PARALLEL TO UPPER WINDS IN NRN TIER OF
STATES...BUT STILL SOME 2-3 MB RISES IN 3 HOURS OVER THE DKTS. THUS
FRONT SHOULD CONTINUE MOVING ALONG SLOWLY. AS OF 16Z IT WAS ALMOST
UPON MSP. LATES RUC TAKES FRONT THROUGH EAU AND AEL LATE AFTERNOON.
SEEMS REASONABLE. LINE OF WEAK SHOWERS APPEARS TO BE ALONG FNT...
THEN HEAVIER RAIN IN NWRN IA.
HEAVY RAIN IS A CONCERN FOR LATER TODAY IN OUR SERN AREA...FROM AEL
TO EAU...AND AMOUNTS MAY APPROACH THE 3 INCH AMOUNTS TYPICAL OF THE
FLASH FLOOD GUIDANCE. FORTUNATELY 12Z UPPER AIR ANLYS SHOWS 40 KNOTS
AT 25H FROM LBF TO MSP...WITH WEAKER SPEEDS FARTHER SE WHERE THE
BEST DIFFLUENCE IS. SHORT WAVE IN SRN MANITOBA WILL MOVE EWD AND
HELP DRAG FASTER FLO A TAD FARTHER SOUTH AS WELL. THUS SOME 2 OR 3
INCH AMOUNTS POSSIBLE FROM AEL TO EAU BUT WL HAVE TO PAY CLOSE
ATTENTION TO PROFILERS AND VAD WIND PROFILES FOR SIGNS THE UPPER
WINDS MIGHT BE WEAKER THAN EXPECTED.
COULD ALSO BE A COUPLE ISOLATED PULSE SVR STORMS AS WELL.
.MSP...NONE
KRAUSE
FXUS63 KDLH 160851 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
700 PM CDT FRI JUL 16 1999
THE PRECIPITATION OVR E KS THAT IS MOVING INTO WEST CENTRAL MO
CONTINUES TO DECREASE IN INTENSITY AND AREAL COVERAGE SINCE 5 PM.
LATEST RADAR IN EASTERN KS HAS THE SAME INDICATION WITH THE MAIN AXIS
OF MOISTURE CONVERGENCE NEAR SFC FRONT IN N KS/SW NE/S IA. ALSO WND
PROFILES AND SATELLITE INFO SHOWING IF ANY PRECIPITATION FORMS IN C
KS WILL LIKELY MOVE S/SE INTO OK. 21Z RUC STILL HAS 85 DP LOW OVR THE
OZARKS AND CONTINUES THROUGH MOST OF THE NIGHT.
WILL LEAVE LOW POPS IN FOR ALL OF CWA/EXCEPT SC MO... BUT WILL DROP
THE SCATTERED SHOWERS OVER WEST CENTRAL MO THIS EVENING.
NO OTHER CHANCES FOR THE REMAINDER OF TONIGHT.
TAGGART
FXUS63 KSGF 162020 AMD mo
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
330 AM CDT THU JUL 15 1999
...FORECAST PROBLEMS INVOLVE CLOUD COVER/PRECIP CHANCES AND THEREFORE
TEMPS...
06Z SFC ANALYSIS HAS MAIN COLD FRONT EXTENDING FROM LOW IN MN SWWD INTO
NERN CO TO S OF THEDFORD TO NEAR BFF...ALTHO NUMEROUS OUTFLOW
BOUNDARIES MAKE IT A TRICK TO FIND. CONVECTION ONGOING AT THIS TIME
ACROSS THE CWA SO WILL MAKE THIS BRIEF. 11-3.9 MICRON IMAGERY SHOWS
CLOUDS DEVELOPING IN HOOKER AND MCPHERSON COUNTIES ATTM WHICH SHOULD BE
THE TREND BASED ON 06Z RUC PROGS AT 850 MB.
PICKING A MODEL OF CHOICE IS DIFFICULT BASED ON THE AMOUNT OF
CONVECTION THAT HAS OCCURRED SINCE THE TIME OF THE 00Z RUNS. ETA HAS
DONE A DECENT JOB IN THE LAST COUPLE OF RUNS SO WILL USE A BLEND OF THE
MODELS WITH MORE WEIGHT ON THE ETA FOR LOW LEVEL RESOLUTION. AT
06Z...THE NGM SFC PATTERN WAS THE CLOSEST...BUT THE STRENGTH OF THE SFC
HIGH IN MT WAS UNDERDONE. AVN LOOKED BETTER FOR THAT. FOR UPPER
FEATURES...ALL ARE NOT DOING TOO BAD WITH FILLING UPPER LOW IN SC
CANADA...BUT ARE LIKELY TOO FAR N WITH NEXT SYSTEM COMING INTO OREGON
AT 06Z.
700-500 MB Q VECTOR PROGS INDICATE SUBSIDENCE TO OVERSPREAD THE CWA
DURING THE DAY...BUT NERLY FLOW AT THE SFC WILL MAKE IT HARD TO CLEAR
OUT CLOUDS THAT DEVELOP THRU THE MORNING ON RESIDUAL MOISTURE NEAR THE
SFC. FOLLOWING RUC/MESOETA FOR THE 1ST PERIOD WOULD HAVE CLOUDS AROUND
FOR MOST OF THE DAY...WITH CLEARING IN THE NWRN CWA BY MID AFTERNOON
THEN WORKING SEWD ITO THE EVENING. SRN PART OF CWA WILL LIKELY GO
SCT-BKN FOR A TIME BY LATE AFTERNOON/EVE...BUT AS WINDS TURN E/SE
OVERNIGHT AND WITH LOW LEVEL MOISTURE REMAINING HIGH...WILL LIKELY SEE
LOW CLOUDS DEVELOP LATE TONIGHT. FORCING REMAINS FAIRLY WEAK UNTIL LATE
TONIGHT WHEN THE MESOETA PROGS A SHORT WAVE TO TOP THE FLAT RIDGE INTO
NRN NEBR BY 12Z SAT. SFC FRONT WILL LIKELY STALL IN CENTRAL KS BUT
WINDS TO THE N WILL HAVE UPSLOPE COMPONENT AND SHOULD FOCUS CONVECTION
IN THE LATE AFTERNOON TO THE FAR WRN PART OF THE STATE. SO WILL INCLUDE
SLIGHT POPS FOR TONIGHT THERE AND NC FOR THIS AFTERNOON AND TONIGHT.
SCT/WDLY WORDING WILL LIKELY BE NEED MOST AREAS THIS MORNIG TO DEAL
WITH ONGOING STUFF.
FOR SAT...DONT HAVE A GOOD FEEL FOR WHERE CONVECTION WILL FIRE. BEST
FORCING WILL BE IN THE W/NRN ZONES WHERE MID LEVEL SHORT WAVE COMBINES
WITH S/SERLY FLOW AT THE SFC. HOWEVER...WITH SOME REMNANTS OF THE FRONT
MOVING BACK N AND WINDS INCREASING FROM THE S...AND HIGH PWS...WILL
INCLUDE POPS ALL AREAS FOR LATE AFTERNOON WHICH GOES ALONG WITH
GUIDANCE.
GUIDANCE HAS BEEN HARD TO BEAT LATELY AND WILL GO ALONG WITH IT FOR THE
MOST PART FOR THIS CAST.
.LBF...NONE.
JWS
ne
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
930 PM EDT FRI JUL 16 1999
AN AREA OF CIRRUS WILL MOVE ACROSS THE SOUTHERN CWA EARLY TONIGHT
FROM EARLIER THUNDERSTORMS ACROSS SC. THERE IS ALSO A SMALL AREA OF
LOW CLOUDS ALONG THE SOUTHERN COAST. SKIES SHOULD STILL CLEAR
TONIGHT...BUT IT MAY TAKE A WHILE...THEREFORE WILL START SKIES
PARTLY CLOUDY AND HAVE THEM BECOMING MOSTLY CLEAR IN SRN ZONES.
BECAUSE DEWPOINTS STILL IN THE LOW 70S ACROSS THE SRN CWA AND NOT
FCST TO DROP MUCH...WILL KEEP LOWS NEAR 70 TONIGHT. WITH VERY LIGHT
WINDS AND MOIST LOW LEVEL...THINK PATCHY FOG IS POSSIBLE...
ESPECIALLY ACROSS NRN INLAND AREAS...WHERE THERE ARE FEWER CLOUDS
ALONG WITH CALM WINDS.
CWF...HIGH PRES WILL DOMINATE TONIGHT WITH LIGHT WINDS. 00Z MHX
SOUNDING SHOWS VERY LIGHT WINDS THROUGH 400 MB. BUOY REPORTS SHOW
VERY LIGHT WINDS AND LATEST RUC AND MESO HAVE WINDS NO HIGHER THAN
10 KT...SO WILL LOWER WINDS TO 10 KT FOR TONIGHT. DIRECTION IS STILL
TRICKY. DSLN7 HAS SHIFTED TO S...WHILE CLOSER TO THE COAST IT IS
MORE FROM THE EAST...OR EVEN NE NEAR DUCK. SO WILL LEAVE CURRENT
FSCT DIRECTION AS IS WITH WINDS E TO NE BECOMING SE.
.MHX...NONE.
BANDY
FXUS62 KILM 170128 nc
AREA FORECAST DISCUSSION.
NATIONAL WEATHER SERVICE WILMINGTON NC
958 AM EDT FRI JUL 16 1999
LATEST MSAS SHOWING SFC RIDGE TO THE NORTH SUPPORTING CONTINUED
LIGHT NE FLOW OVER ALL OF CWA. LITTLE EVIDENCE OF OLD BNDRY EXCEPT
PERHAPS SOME WEAK CONVERGENCE WELL OFF SHORE ASSOCD WITH CONVECTION.
WV IMAGERY IMPLYING COMPLEX MID LVL FLOW PATTERN CNTRL APPLCNS LOWER
OH VLY. IMAGERY ALSO SHOWING CLEARLY DEFINED SHRTWV RIDGE AND ASSOCD
MSTR PLUME LIFTING OVER CWA. ISOLATED SHWRS/CNVTN INLAND WITH MORE
WIDESPREAD ACTIVITY OFF COAST. GSO/MHX MORNING SOUNDINGS MUCH DRYER
WHILE CHS STILL SOUPED UP. UNFORTUNATELY CWA IN AMS TRANSITION ZONE.
MODELS GENERALLY NOT MUCH HELP IN DEFINING FOCUS MECHANISM THUS
STILL THINK LOW POPS BEST. HOWEVER..HAVE NOTED NEW RUC DOES DEPICT
WEAK VORT LOBE/MAX ACROSS SC NEXT 12HRS. WILL CONTINUE SUGG OF
BETTER PCPN CHANCES AND CLD COVER FOR SC ZONE AND TRANSITION TO
SLGTLY BETTER CONDITIONS FOR NC ZONES.
CWF:MAY SPLIT UP ZONES BASED ON POTENTIAL FOR ISOLATED SHWR/CNVTV
ACTIVITY. OTRWS LOOKS OKAY.
.ILM...NONE.
RWA
FXUS62 KMHX 161346 nc
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
958 AM CDT FRI JUL 16 1999
...AFTERNOON FORECAST CHALLENGE IS CLOUDS/-SHRA IN NORTH...
LINE OF IFR/MVFR CIGS MOVING THRU NRN RRV INTO NW MN ATTM IN
ASSOCIATION WITH TD DISCONTINUITY WITH 40S BEHIND IT AND 60S AHEAD.
STILL DEALING WITH CLOUD IN EASTERN CWA BEHIND INITIAL COLD FRONT
WITH W/SW FLO ALOFT SLOWING ITS PROGRESS. MSAS SHOWING RUSH OF CAA
APPROACHING RRV WITH TEMPS DOWN INTO LOWER 50S IN NW CWA.
WV LOOP SHOWS U/L LO SPINNING JUST EAST OF SASK/MB BORDER...QUITE
CLOSE TO 12Z RUC FCSTD POSITION FOR 15Z. SFC ANLYSIS YIELDS E/W
ORIENTATED COLD FRONT JUST NORTH OF YBR AT 13Z. MOISTURE WITH SCT
-SHRA JUST BEHIND FRONT IN SASK/MB SINKING SLOWLY SE. TRACK OF U/L
SKIMS IT ACROSS INTL BORDER IN QUICK W FLO AND THEN DIPS IT BIT SE
THRU NW MN BY 21Z-00Z. AMPLE 925-850MB MOIST DROPPING SE SHOULD
CLOUD OVER NRN CWA THRU AM HOURS EVEN THO MAIN SFC FRONT SHOULD NOT
MAKE TOO MUCH PROGRESS SWRD THRU CWA. TAIL OF PVA SWEEPING ACROSS
NRN CWA ALSO IN AFTN WITH LI/S 0 TO +2 EXTREME NORTH SO ISOLD -SHRA
STILL POSSIBLE IN PEAK DAYTIME HEATING HOURS. THINK SUBSIDENCE FROM
APPROACHING HI PRES WILL SPREAD ACROSS ND LATER IN AFTN AND SHIFT
BETTER CHANCE INTO NW MN WHERE MODEL INDICATES SOME WEAK UVM WITH
HELP FROM EXITING U/L JET. FURTHER SOUTH APPEARS LACK OF PUSH OF
COOLER AIR ALOFT AND NVA SHOULD ALLOW FOR MORE SUN AND MINIMAL
SHRA CHANCE.
WILL UPDATE NRN ZONES TO READ BCMNG MCLDY AS PER SAT TRENDS AND
NUDGE FEW TEMPS DOWNWARD ALSO IN NORTH. WILL LEAVE SHRA CHANCE IN
WHERE CURRENT ZONES INDICATE. NO CHANGE TO WINDS AS BREEZY
CONDITIONS HAVE ALREADY DEVELOPED.
UPDATE OUT BY 1015 AM.
.FGF...NONE.
SOROKA
nd
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1045 AM CDT FRI JUL 16 1999
CURRENT FORECAST LOOKS TO BE ON TRACK FOR THE MOST PART. LATEST RUC
KEEPS MOISTURE PLUME TO THE WEST OF FA...AND SFC FRONT DRAPED ACROSS
KS IS PROGGED TO MOVE LITTLE. 12Z RAOBS INDICATE 40KT H85 JET TO THE
WEST OF FA WHICH HAS LIKELY AIDED THE ONGOING CONVECTION OVER NC OK
ANS SRN KS THIS MORNING. LOW POPS OVER ALL OF FA LOOK GOOD FOR THIS
AFTERNOON. ONLY CHANGE WAS TO TWEAK TEMPERATURES OVER FAR NW AR
ZONES. NO CHANGES TO LATER PDS.
UPDATED ZONES ALREADY SENT.
FCSTID = 23
.TUL...
AR...NONE.
OK...NONE.
FXUS64 KOUN 160919 ok
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
400 AM CDT FRI JUL 16 1999
PROBLEM(S) OF THE DAY:
TEMPERATURES
WILL THERE BE CONVECTION?
STORMS IN CENTRAL KANSAS ARE DIMINISHING AND MOVING MORE EAST.
SHOWERS HAVE DEVELOPED ALONG WESTERN EDGES OF FORECAST AREA IN THE
LAST COUPLE OF HOURS. THESE APPEAR TO BE ASSOCIATED WITH A WEAK UPPER
VORT MOVING NORTH THROUGH THE AREA. 03Z RUC ONLY MODEL TO HINT AT
THIS DEVELOPMENT...AS VORT MOVES TO THE NORTH SHOWERS WILL DISSIPATE
BY LATE MORNING.
BEST CHANCE OF SHOWERS AND THUNDERSTORMS TODAY STILL REMAINS WITH
REDEVELOPMENT OF STORMS ALONG FRONT IN SOUTHEASTERN KANSAS THIS
AFTERNOON AND EVENING. BIG QUESTION IS WHETHER OR NOT ANY STORMS WILL
MAKE INTO FORECAST AREA. MODELS INDICATE THAT H700 AND H500 MOISTURE
PLUME WILL REMAIN ORIENTED ALONG THE FRONT JUST NORTH OF COUNTIES
ALONG KANSAS BORDER. HAVE HIGHEST POPS IN FOR THIS ARE...BUT JUST
SLIGHT CHANCE.
MODELS ARE IN FAIRLY GOOD AGREEMENT ON LOWS...STAYED CLOSER TO COOLER
FAN FOR HIGHS.
AS FRONT WASHES OUT...MAINLY AFTERNOON AND EARLY EVENING STORMS WILL
DEVELOP THROUGH EXTENDED PERIODS.
FCSTID = 33
TUL 93 74 94 73 / 20 20 20 10
FSM 92 74 93 71 / 10 10 20 10
MLC 91 74 93 74 / 10 10 20 10
BVO 92 73 93 72 / 20 20 20 10
FYV 89 69 90 68 / 20 10 20 10
BYV 89 69 90 68 / 20 10 20 10
MIO 91 70 91 69 / 20 20 20 10
MKO 93 74 94 73 / 10 10 20 10
F10 92 74 93 74 / 10 10 20 10
HHW 94 72 96 72 / 10 10 20 10
.TUL...
AR...NONE.
OK...NONE.
--------------------
EXPERIMENTAL OUTPUT:
HAZARDOUS WEATHER EXPECTED NEXT 24 HOURS: NONE
NGM CONFIDENCE: 8 ON A SCALE OF 0 TO 10
ETA CONFIDENCE: 8 ON A SCALE OF 0 TO 10
AVN CONFIDENCE: 8 ON A SCALE OF 0 TO 10
FCST CONFIDENCE: 8 ON A SCALE OF 0 TO 10
ok
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
912 PM EDT FRI JUL 16 1999
KGSP SHOWING TSRA DIMINISHING ATTM. THIS TREND SHOULD CONTINUE WITH
THE LOSS OF DAYTIME HEATING. HOWEVER LATEST RUC AND 18Z ETA KEEP
WEAKNESS IN RIDGE AND GOOD MOISTURE ACROSS MTNS SO SOME ADDITIONAL
DEVELOPMENT POSSIBLE. WILL REMOVE POPS UNLESS ADDITIONAL DEVELOPMENT
OCCURS BEFORE ISSUANCE. DENSE VALLEY FOG THIS MORNING IN NC MTNS SO
FOG WORDING TO REMAIN. TEMPS THIS MORNING WERE A LITTLE COOLER THAN
FCST OUTSIDE OF THE MTNS. WILL CHECK LATEST READINGS TO SEE IF
ADJUSTMENTS ARE NECESSARY.
.GSP...NONE.
RWH
FXUS62 KCHS 170100 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1030 AM EDT FRI JUL 16 1999
SURFACE/UPPER RIDGING IS KEEPING THE WEATHER QUIET ACROSS THE WESTERN
CAROLINAS THIS MORNING. MODIFIED MORNING RAOBS SHOW CAPE OF AROUND 2200
J/KG AT FFC...AND AROUND 1700 J/KG AT GSO WHERE WARM MID LEVEL TEMPS ARE
LIMITING CAPE TO A GREATER EXTENT. HOWEVER...THERE DOES NOT APPEAR TO
BE MUCH FORCING TO ACT UPON THIS INSTABILITY. OF MINOR CONCERN IS POOL
OF COOLER AIR AT 500 MB (TEMPS AROUND MINUS 10 C) TO OUR IMMEDIATE
NW...BUT MODELS KEEP THIS COOL POOL OUT OF THE FCST AREA TODAY. 12Z RUC
AND 03Z ETA SHOW SOME LOW LEVEL MOISTURE CONVERGENCE OVER THE MOUNTAINS
THIS AFTERNOON...WHERE ONE MIGHT EXPECT A SLIGHTLY BETTER CHANCE OF DEEP
CONVECTION ANYWAY. FORTUNATELY...THE CURRENT SET OF ZONES HAS THIS
COVERED. ONE MINOR CHANGE WILL BE TO SPLIT OUT THE NORTHERN FOOTHILL
ZONES TO ADD A SLIGHT CHANCE OF TSRA THIS AFTERNOON...MAINLY FOR THE
POTENTIAL FOR DEVELOPMENT CLOSE TO THE BLUE RIDGE ESCARPMENT SIMILAR TO
YESTERDAY. TEMPS LOOK FINE AND ONLY CHANGES MIGHT BE MINOR TWEAKS.
.GSP...NONE.
MOORE
FXUS62 KCHS 161401 sc
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
900 PM MDT FRI JUL 16 1999
AT 02Z SFC MAP SHOWS HI PRES RIDGE EXTENDING FM CENT CANADA SE THRU
NE MT AND THE DAKOTA'S. 00Z RUC SHOWS STG S/W FM 500-700 MB IN SW
WYOMING. THIS S/W IS PROGD TO MV NE SLWLY AND BE NR CPR BY 12Z.
LKS LIKE BEST PVA WITH THIS WL BE LATER TONIGHT ACRS NE WY AND BLACK
HILLS.
SCT SHWS SHOWING UP IN ERN WY ON 88D...ACROSS CAMPBELL CTY AND PTS
SOUTH. WL UPDATE ZONES TO TAKE POPS OUT OF NE WYM AND JUST GO SCT
SHWS/TSTMS. WILL MAKE SOME MINOR ADJUSTMTS TO WINDS BUT WL LEAVE
REST OF FCST ALONE AS IT LKS GD.
.UNR...NONE.
LJC
FXUS63 KABR 170158 sd
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1040 AM CDT SAT JUL 17 1999
WELL DEFINED VORT MAX ON VISIBLE STLY MOVING NE THROUGH NW IA AND PICKED
UP WELL BY 12Z RUC. ALTHOUGH CAA TAKING PLACE IN CWA...PVA
CONTRIBUTIONS AND LO LVL CONVERGENGE PROVIDING ENOUGH LIFT TO BRING
TSTMS WITH HVY RAIN TO PARTS OF NW IA THIS MRNG WHICH WAS HANDLED
WELL THROUGH A 920 AM NOWCAST. WL UPDATE ZONES BEFORE NOON TO WIND
DOWN MRNG PCPN ALONG WITH PSBL TWEAKS IN TEMPS AND WNDS. ALTHOUGH HI
PRES MOVNG INTO THE NRN PLAINS...PRES GRADIENT REMAINS QUITE
STRONG TDY WITH RUC INDICATING 20KT WNDS AROUND 18Z THEN DECREASING
LATER IN THE AFTN. DRY AIR ADVECTING INTO THE AREA HELPING TO
STABILIZE ATMOSPHERE TDY...THOUGH SOME ISOLATED SHOWERS MAY STILL BE
POSSIBLE IN THE CWA DURING THE LATE AFTN.
.FSD...NONE
BR
FXUS63 KUNR 161446 sd
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
900 AM MDT FRI JUL 16 1999
CURRENT SURFACE MAP SHOWS HIGH PRESSURE OVER CENTRAL MONTANA...WITH
COLD AIR ENTRENCHED OVER WESTERN SOUTH DAKOTA. 12Z UPPER AIR MAPS
SHOWS PLENTY OF COLD ADVECTION AT 850MB THIS MORNING WITH KRAP AT
+10C AND KGGW AT +1C. A DIFFERENT STORY AT 700MB WITH WARM AIR
ADVECTION OCCURING WITH SOUTHWEST WINDS. THIS HAS RESULTED IN DECK
OF ALTOCUMULUS OVER NORTHEAST WYOMING/WESTERN SOUTH DAKOTA.
12Z RUC INITIALIZED WELL WITH THE CLOUDS AND TEMPERATURES. THE RUC
SLOWLY DISSIPATES CLOUDS AND MOVES THE EAST DURING THE DAY...AND
BRINGS IN SOME WARMER 850 MB TEMPERATURES. CURRENT FORECAST HAS A
GOOD HANDLE ON THE SITUATION...AND UPDATE WILL MAINLY BE TO REMOVE
MORNING SHOWERS.
.UNR...NONE.
KRC
FXUS63 KABR 160917 COR sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1010 AM EDT FRI JUL 16 1999
HIGH PRESSURE CENTERED OVER THE REGIONAL WILL CONTROL OUR WEATHER
INTO THE WEEKEND. MORNING LOW CLOUDS AND FOG WILL LIFT QUICKLY THIS
MORNING. THIS MORNINGS SOUNDINGS SUPPORTED HIGH TEMPS FROM THE MID 80S
TO AROUND 90. MODIFIED RNK 12Z SOUNDING INDICATED THAT WE COULD
BREAK OUR CAP AROUND 2 DEGREES WITH AN LI 0F MINUS 5. SOME LOW LEVEL
CONVEREGENCE COMBINED WITH ORGRAPHIC LIFT SHOULD CREATED A FEW
THUNDERSTORMS IN THE MOUNTAINS. THE MEAN WIND FLOW SUGGEST SLOW
MOVERS WITH RAIN AROUND AN INCH PER RAOBS PCP WATER VALUES. THIS
MORNINGS RUC AND MM5 SE RUNS ALSO SUPPORT THE MENTION OF A CHC OF
A SHOWER OR THUNDERSTORM. EARLIER RUNS OF ETA/NGM ALSO INDICATED
THAT THE BEST INSTABILITY WILL BE IN THE WEST. ONLY MINOR CHANGES
FOR AFTERNOON ZONE PACKAGE. HAVE A GUD AFTERNOON.
.RNK...
VA...NONE.
NC...NONE.
WV...NONE.
KK
FXUS61 KAKQ 161414 va
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
945 PM CDT FRI JUL 16 1999
WILL BE UPDATING ZFP ONCE AGAIN TO ACCOUNT FOR THE LATEST STLT AND RADAR
TRENDS. IR STLT LOOP SHOWS CLD SHIELD SHIFTING STEADILY EAST. RADAR
SHOWS ONE AREA OF RAIN OVER E-C WI SHIFTING E OVER LK MICHIGAN. NEXT
AREA TO THE WEST IS PROGRESSING STEADILY EAST...BUT DIMINISHING. 00Z RUC
SUGGESTS MID-CLDS WILL CLEAR THE NW 2/3 OF MY FCST AREA BY 12Z. CLEARING
SKIES...LGT WINDS...AND PLENTY OF MOISTURE FROM THE RAINS SHOULD LEAD TO
SOME DENSE FOG FORMATION. WILL ADD CLEARING SKIES AND MENTION OF AREAS
OF DENSE FOG IN THE N-C...C...AND NE WI. LINGERING MID-CLDS SHOULD HELP
PREVENT DENSE FOG IN E-C WI...BUT WILL STILL MENTION SOME FOG THERE.
.GRB...NONE.
SKOWRONSKI
WWW.CRH.NOAA.GOV/GRB
FXUS63 KARX 170217 wi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
830 PM CDT FRI JUL 16 1999
FCST FOCUS CENTERS ON IA VORT CNTR AND INCOMING CDFNT.
SATL WATER VAPOR IMAGRY SHOWS WEAK SHRTWV ENTERING WI. HWVR WINDS IN
MID/UPR LEVELS WEAK...SO UPR DYNAMICS ARE LACKING. MDT SW WNDS AHD
OF CDFNT BELOW 700 MB...BUT CONVERGENCE ALONG FRONT IS WEAK.
THEREFORE MAIN INGREDIANT WITH TSTMS IS FAVORABLE THERMODYNAMICS.
00Z RUC SOUNDING OVR MSN SHOWS CAP GONE WITH FREE RIDE UP TO 43 THSD
FT. HWVR MOST TSTM TOPS ARND 40 THSD FT...WITH NONE EXCEEDING
EQUILIBRIUM LEVEL. THEREFORE MAIN THREAT WITH THESE STORMS SHLD BE
BRIEF HEAVY RAIN. PRECIP WATER ARND 1.75 WITH CAPES NEAR 2000. OUR
FCST AREA SHUD BE ABLE TO HANDLE QUITE A BIT OF RAIN WITH HIGH
FFG VALUES. WITH LACK OF STRONG CONVERGENCE MOST HEAVY RAIN HAS
BEEN BRIEF...AND AFFECTING SMALL AREAS AT ONE TIME.
WET BULB ZERO ARND 12000 FT SO HAIL THREAT IS LOW THIS EVE.
.UW-NMS...NOT AVAILABLE.
.MKX...NONE.
HENTZ
FXUS63 KGRB 170021 wi
SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO
300 AM MDT SAT JUL 17 1999
...FLASH FLOOD THREAT INCREASING ACROSS SE CO INCLUDING I-25
CORRIDOR AREA...
CURRENTLY...IMPRESSIVE MCS OVER THE REGION. SAT IDATA AND ANALYSIS
OF 00Z UPPER LEVEL WIND FIELDS NDICATING EXCELLENT ANTICYCLONIC
OUTFLOW AT UPPER LEVELS. LOCALLY...TRAINING OF STORMS OCCURRING IN
LHX AREA AND QUITE A BIT OF RAIN HAS FALLEN LOCALLY IN THIS AREA.
LAPS ANALYSIS PARAMETERS INDICATING MOST UNSTABLE AIR AND CONVG IN
THIS REGION. MID 60 DWPTS FEEDING INTO SYSTEM.
SHORT TERM WILL OBVIOUSLY BE FLOOD THREAT IN LHX AREA. RUC INDICATES
EASTERLY MOIST FLOW WILL CONTINUE TO FEED INTO THIS REGION. WILL
CONTINUE TO MONITOR AREA FOR UPGRADE IF PRECIP CONTINUES.
...BASED ON REPORTS OF RESCUES OF MOTORISTS...FFW ISSUED AT 200 AM...
FORECAST...PLENTY OF JUICE TO REMAIN IN AREA AS LEE TROUGH TO BACK
WEST ALONG THE MOUNTAINS. PWATS VALUES TO CHANGE VERY LITTLE WITH
TIME. ALSO CONVECTION HAS PUSHED OUTFLOW BOUNDARY UP ALONG MTNS.
DWPTS IN THE 60S EVERYWHERE IN FA (PLAINS). I AM OBVIOUSLY GOING TO
MENTION HVY RAINS IN THE ZONES. FCST TEAM HERE AT PUB CONTEMPLATED A
FLASH FLOOD WATCH FOR AREA. DECIDED AGAINST THIS ATTM FOR THE
FOLLOWING REASONS.
1. ANTICPATE LOCAL HVY THUNDERSTORM RAINS TO DEVELOP DURING
AFTERNOON TIME PD...WHICH IS 18 HOURS OFF.
2. LET DAY SHIFT GET A BETTER FEEL FOR MORNING SOUNDINGS/WAT VAP
SHOTS TO GET FEEL FOR SHORT WAVES OF THE DAY AND MOISTURE PROFLIES
ACROSS REGION. ALSO THEY WILL HAVE BETTER FEEL FOR BOUNDARIES ACROSS
AREA.
3. SYNOPTICALLY...CLASSIC FLOOD THREAT NOT OBVIOUS IN FCST DATA (NO
DOSWELL PATTERNS EVIDENT).
STRONGLY ENCOURAGE MEDIA TO MENTION LOCAL HVY RAIN THREAT THIS
AFTERNOON/EVENING IN TV/RADIO PRODUCTS THIS MORNING FOR ALL OF SE
COLORADO INCLUDING I-25 CORRIDOR AREA...FLASH FLOOD WATCH MIGHT BE
ISSUED BY DAY SHIFT AT ANY TIME IF CONDITIONS WARRANT.
SIG WEATHER OUTLOOK WILL BE WORDED HARD FOR FLOOD THREAT.
SUNDAY...MODELS HINTING AT SLIGHT DRYING. DO NOT BELIEVE IT AS LEE
TROUGH STILL BANKED UP AGAINST MTNS. WILL KEEP THUNDER CHANCES HIGH
THROUGH WEEKEND.
AS FOR EXTD...NOT TOO CONFIDENT ABOUT DRY IN FCST...AS IMPRESSIVE
SHORT WAVE TOMOVE ACROSS UTAH IN EXTD PD WHICH SHOULD KEEP TROUGH
BANKED UP ALONG ROCKIES...KEEPING AREA IN THREAT FOR PRECIP. WILL
ALLOW DAY SHIFT TO MAKE UPDATES WITH LATER AVN RUNS.
HODANISH
.PUB...NONE.
FXUS65 KBOU 162101 co
SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO
249 PM MDT FRI JUL 16 1999
TNGT/SAT: 19Z/16 SURFACE ANALYSIS HAD SHALLOW FRONTAL BOUNDARY FROM
KGCK-KSPD-KCOS-KCAG WITH "TRUE" COLD FRONT ACROSS THE DAKOTAS
THROUGH SOUTHERN WY INTO ID. KPUB 88D VAD WIND PROFILE SHOWING
ABOUT 8000 KT DEEP NORTHEAST-EAST FLOW. TWO MAIN CONCERNS TONIGHT
WILL BE MINOR SHORTWAVE PRESENTLY MOVING THROUGH WESTERN CO AND
UPSLOPE THREAT ACROSS SOUTHEASTERN CO MOUNTAINS AND ADJACENT
PLAINS. LATEST RUC/ETA HAVING A TOUGH TIME HANDLING WESTERN CO
SHORTWAVE BY TAKING IT TOO FAR NORTH AND WEST. CURRENT MANUAL
PROJECTION TAKE IT THROUGH CENTRAL AND EASTERN CO TONIGHT. LATEST
REGIONAL 88D/LIGHTNING DETECTION IMAGERY SHOWED WIDELY
SCATTERED/SCATTERED SHRA/TSRA BREAKING OUT IN THE CENTRAL AND
SOUTHEAST MOUNTAINS. GREATEST COVERAGE...SO FAR...IS IN UPPER
HUERFANO AND UPPER PURGATOIRE RIVER BASINS(74/75). MOISTURE
CERTAINLY NOT A PROBLEM. SURFACE DEW POINTS HAVE CLIMBED INTO THE
MID 50S/MID 60S ALONG AND EAST OF I-25 THIS AFTERNOON. WITH
COMBINATION OF MID-LEVEL SHORTWAVE AND EVENING UPSLOPE EASTERLY...
PLAN TO CARRY "LIKELY" WORDING FOR SANGRE DE CRISTO/WET MOUNTAINS
INCLUDING ZONES 74/75 TONIGHT. WILL GO WITH WIDELY SCATTERED/
SCATTERED COVERAGE IN THE PLAINS. WILL NOT CARRY A "TIMER" ON
PRECIPITATION WORDING FROM SOUTHEAST MOUNTAINS INTO THE PLAINS.
SHRA/TSRA MAY HANG ON A LITTLE LONGER WITH EXPECTED SHORTWAVE...
ALBEIT WEAK...MIGRATING THROUGH CWA. IN THE SOUTHWEST MOUNTAINS...
UPPER AR RIVER VALLEY...AND SAN LUIS VALLEY...SHRA/TSRA SHOULD BE OF
DIURNAL CHARACTERISTICS. WOULDN'T BE SUPRISED TO SEE STRATUS
POSSIBLY FORM IN THE PLAINS TONIGHT. NOT EXPECTED SIGNIFICANT
WIDESPREAD FOG...SO WILL NOT MENTION. LOWER TROP FLOW EXPECTED TO
GO MORE SOUTHERLY ON SAT WITH PLENTY OF RELATIVELY DEEP MOISTURE IN
PLACE. 500MB HEIGHTS START TO RISE WITH THE POTENTIAL FOR LOW LEVEL
SOUTHEASTERLY UPSLOPE FLOW DRIVEN SHRA/TSRA. PLAN TO MAINTAIN LOW
"CHANCE" POPS AND WORDING IN CURRENT ZFP. DAY 2 QPF HAS .25-.50"
PRECIPITATION DRAWN GENERALLY ALONG THE EASTERN MOUNTAINS.
SAT NGT/SUN: 500MB HEIGHT EXPECTED TO CONTINUE RISING AS A SERIES OF
MID-LEVEL SHORTWAVES EJECT ACROSS PACIFIC NORTHWEST FROM DEEPENING
LONGWAVE ALONG WEST COAST. SHRA/TSRA THREAT WILL LIKELY BE LESS AND
LESS WITH THE QUALITY OF DEPTH OF MOISTURE DECREASING AND MID-LEVEL
TEMPERATURES ON THE RISE. SHOULD SEE MORE OF A DIURNAL WIDELY
SCATTERED/SCATTERED SHRA/TSRA ACTIVITY ON SUN. SURFACE TEMPERATURES
TO INCREASE BACK INTO SUMMERTIME READINGS.
EXTENDED(MON-WED): LONGWAVE TROUGH WILL CONTINUE TO DEEPEN ALONG THE
WEST COAST ON MON WITH ANTICYCLONE TAKING SHAPE IN THE HEARTLAND OF
U.S. STILL SUFFICIENT AMOUNT OF MOISTURE TO GENERATE MAINLY
AFTERNOON AND EVENING SHRA/TSRA...ESPECIALLY IN MOUNTAINS. PLAN TO
LEAVE GENERIC "CHANCE" WORDING IN FOR MON. MRF CONTINUES TO HAVE
GOOD RUN-TO-RUN CONTINUITY ON BUILDING LARGE UPPER ANTICYCLONE INTO
CO/KS ON TUE-WED. 700MB TEMPERATURES STILL PROGD TO BE +16-20 C.
MRF IN PAST CASE SEEM TO BE OVERDONE ON THE 700-300MB MEAN RH AND
MAY BE CONTINUING THIS PRACTICE. BELOW 500MB...MEAN RH EXPECTED TO
RANGE FROM 10-20%. FEEL THREAT IS SO LOW ITS TOO EARLY TO MENTION AND
WILL WAIT UNTIL TUE-WED FORECAST GETS INTO THE SHORT RANGE TO FINE
TUNE. STILL COULDN'T RULE OUT AN ISOLATED TSRA IN MOUNTAINS...BUT TOO
FAR TO MENTION. MAIN WEATHER FEATURE TUE-WED SHOULD BE SUMMERTIME
HEAT AND A RETURN TO NEAR 100 DEG READINGS IN FAVORED AREAS
THROUGHOUT THE PLAINS.
.PUB...NONE.
METZE
FXUS65 KGJT 161831 co
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1115 AM CDT FRI JUL 16 1999
COLD FRONT CURRENTLY MOVING THROUGH NORTHWEST WISCONSIN. SHOWERS
ALONG THIS LINE AND WITH UPPER LVL SHORTWAVE...BOTH OF WHICH
CONTINUED TO WEAKEN. MSAS STILL SHOWING LI'S TO -5 AHEAD OF FRONT...
AND BOTH RUC AND ETA INDICATING CONDITIONS TO REMAIN SOMEWHAT
UNSTABLE THERE. HOWEVER BEST LIFT AND INSTABILITY WILL BE SOUTH OF
WISCONSIN CWA. ADDITIONAL LIFT FROM IOWA VORT LOOKS LIKE IT WILL ALSO
PASS TO THE SOUTH AS WELL. SO WILL KEEP THE MENTION OF THUNDERSTORMS
ALONG AND AHEAD OF FRONT...BUT AM NOT CONCERNED ABOUT SEVERE WEATHER
FOR ONCE.
FURTHER WEST...ANOTHER TROUGH PUSHING INTO WESTERN MINNESOTA WITH
MUCH DRIER AIR BEHIND IT. THIS WILL BRING INCREASING SUNSHINE TO
MUCH OF NORTHEAST MINNESOTA. HOWEVER...VORT SCOOTING ACROSS SOUTHERN
MANITOBA TO BRING MORE CLOUDS AND PERHAPS A FEW SHOWERS TO PORTIONS
OF NORTH CENTRAL MINNESOTA THIS AFTERNOON. CONDITIONS SHOULD REMAIN
STABLE ENOUGH TO PREVENT THUNDERSTORM DEVELOPMENT HERE.
PREVIOUS FCST TEMPS STILL LOOKING GOOD. WESTERLY WINDS WILL CAUSE
COMPRESSIONAL WARMING ALONG NORTH SHORE TO SUW.
.DLH...NONE.
TAP
FXUS63 KMPX 161601 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
240 AM CDT SAT JUL 17 1999
SHOWERS AND THUNDERSTORMS WITH POTENTIAL FOR HEAVY RAIN MAIN FCST
CONCERN AS FNTL BNDRY STALLING ACROSS NRN MO AND EXTRM NRN KS LIFTS NWD
AS WMFNT TDAY THRU TNGT.
SHOWERS AND A FEW TSTMS ALREADY STARTING TO REDEVELOP IN SE NEB AS
START OF LWR LVL WAA AND LIFTING OVER BNDRY ENSUES. CLOUDINESS ALSO
BEGINNING TO DEVELOP AGAIN NWD INTO PTNS E CNTRL NEB AND SW IA. BASED
ON STLT TRENDS AND MODEL RH AS ETA AND RUC...PROCESS LIKELY TO CONTINUE
WITH CLOUDINESS THICKENING ACROSS REST OF CWFA FM SW TO NE TDAY WITH
INCREASING CHC FOR SHOWERS AND TSTMS. EXCEPT FOR SE NEB HIGHEST
LIKLIHOOD FOR SHWRS/TSTMS APPEARS TO BE LATER THIS AFTN THRU TNGT AS
STRENGTHENING LWR LVL WINDS MAXIMIZE STRONG POSITIVE THETA ADVECTION
AND MOISTURE CONVERGENCE INTO BNDRY. WITH ARND 15C H85 DEWPOINTS AND
70-75F SFC DEWPOINTS INTO BNDRY ALNG WITH SUBTROPICAL MOISTURE FEED
EVIDENT ON STLT LOOP INCREASING INTO AREA...THE HIGH PWS WITH RISK OF
MCC AND HEAVY RAINFALL REASONABLE. ETA AND NGM APPEAR TO HAVE BETTER
HANDLE ON THIS EVOLUTION. WILL NOT ISSUE FFA ATTM...HOWEVER ONE MAY BE
REQUIRED LATER IN DAY AS SITUATION UNFOLDS.
APPEARS MAIN RISK FOR SHOWERS AND THUNDERSTORMS WILL END SUNDAY MRNG AS
BNDRY LIFTS NWD AND UPPER RIDGE BLDS MORE OVER AREA. GUID MX TEMPS
RSNBL. HOWEVER BASED TEMPS VICINIITY AND S OF FNT WILL LIKLELY RAISE
MIN TEMPS FCST ARND 5 DEGREES OR SO OVER MIN TEMP GUIDANCE.
.OMA...NONE
WIESE
FXUS63 KOAX 161952 ne
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
930 PM EDT FRI JUL 16 1999
AN AREA OF CIRRUS WILL MOVE ACROSS THE SOUTHERN CWA EARLY TONIGHT
FROM EARLIER THUNDERSTORMS ACROSS SC. THERE IS ALSO A SMALL AREA OF
LOW CLOUDS ALONG THE SOUTHERN COAST. SKIES SHOULD STILL CLEAR
TONIGHT...BUT IT MAY TAKE A WHILE...THEREFORE WILL START SKIES
PARTLY CLOUDY AND HAVE THEM BECOMING MOSTLY CLEAR IN SRN ZONES.
BECAUSE DEWPOINTS STILL IN THE LOW 70S ACROSS THE SRN CWA AND NOT
FCST TO DROP MUCH...WILL KEEP LOWS NEAR 70 TONIGHT. WITH VERY LIGHT
WINDS AND MOIST LOW LEVEL...THINK PATCHY FOG IS POSSIBLE...
ESPECIALLY ACROSS NRN INLAND AREAS...WHERE THERE ARE FEWER CLOUDS
ALONG WITH CALM WINDS.
CWF...HIGH PRES WILL DOMINATE TONIGHT WITH LIGHT WINDS. 00Z MHX
SOUNDING SHOWS VERY LIGHT WINDS THROUGH 400 MB. BUOY REPORTS SHOW
VERY LIGHT WINDS AND LATEST RUC AND MESO HAVE WINDS NO HIGHER THAN
10 KT...SO WILL LOWER WINDS TO 10 KT FOR TONIGHT. DIRECTION IS STILL
TRICKY. DSLN7 HAS SHIFTED TO S...WHILE CLOSER TO THE COAST IT IS
MORE FROM THE EAST...OR EVEN NE NEAR DUCK. SO WILL LEAVE CURRENT
FSCT DIRECTION AS IS WITH WINDS E TO NE BECOMING SE.
.MHX...NONE.
BANDY
FXUS62 KILM 170128 nc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
912 PM EDT FRI JUL 16 1999
KGSP SHOWING TSRA DIMINISHING ATTM. THIS TREND SHOULD CONTINUE WITH
THE LOSS OF DAYTIME HEATING. HOWEVER LATEST RUC AND 18Z ETA KEEP
WEAKNESS IN RIDGE AND GOOD MOISTURE ACROSS MTNS SO SOME ADDITIONAL
DEVELOPMENT POSSIBLE. WILL REMOVE POPS UNLESS ADDITIONAL DEVELOPMENT
OCCURS BEFORE ISSUANCE. DENSE VALLEY FOG THIS MORNING IN NC MTNS SO
FOG WORDING TO REMAIN. TEMPS THIS MORNING WERE A LITTLE COOLER THAN
FCST OUTSIDE OF THE MTNS. WILL CHECK LATEST READINGS TO SEE IF
ADJUSTMENTS ARE NECESSARY.
.GSP...NONE.
RWH
FXUS62 KCHS 170100 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1004 AM EDT SAT JUL 17 1999
CURRENTLY...AT 9 AM SATELLITE...SURFACE...AND RADAR SHOWED A VORT MAX
OVER NORTHEASTERN GEORGIA MOVING NORTHEAST. A LOW WAS NORTH OF CUBA
MOVING NORTHWEST. THE E/W SURFACE RIDGE AXIS WAS ACROSS NORTHERN
GEORGIA/NORT CAROLINA AREA. THE RUC/ETA SHOWED SOME WEAK VORTICITY
OVER NORTHWESTERN GEORGIA WHICH COULD ENHANCE THUNDERSTORM ACTIVITY
OVER THE NORTHWESTERN PORTION OF THE NORTHEAST FLORIDA/SOUTHWEST
GEORGIA THIS AFTERNOON...OTHERWISE SEABREEZE INTERACTION WILL
DICTATE SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA TODAY.
STORM MOTION INDICATE NEARLY STATIONARY STORMS SO MAIN THREAT THIS
AFTERNOON APPEAR TO BE FLOODING. MORNING ZONES LOOKS GOOD.
BLS
FXUS72 KMFL 171345 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
554 AM MDT SAT JUL 17 1999
DRIZZLE HAD DEVELOPED ACROSS MOST OF THE CWA THIS EARLY MORNING. ALSO
THE LATEST RUC INDICATED MID LVL MOISTURE PERSISTING THROUGH MIDDAY
THEREFORE...HAVE UPDATED MOST OF THIS MORNINGS ZONES TO REFLECT THIS.
.GLD...FLASH FLOOD WATCH TODAY FOR A PORTION OF THE EASTERN COUNTY
WARNING AREA THAT INCLUDES THE FOLLOWING KANSAS ZONES KSZ004-015-016-
029.
VPAPOL
FXUS63 KGLD 170914 AMD ks
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1140 AM EDT SAT JUL 17 1999
MAIN FCST CONCERNS THIS AFTERNOON INCLUDE CLOUDS/TEMPS.
MID/UPR LVL ZONAL PATTERN DOMINATES WESTERN GREAT LAKES. SFC HI PRES
WAS BUILDING TOWARD THE AREA AS SFC HI OVER SRN MANITOBA EDGES
TOWARD LAKE SUPERIOR. UPR MI WL BE UNDER SYNOPTIC SCALE SUBSIDECNE
THIS AFTERNOON WITH 250 MB CONVERGENCE AND 305-310K ISENTROPIC
DESCENT. VIS LOOP INDICATED EXTENSIVE CU FIELD NW OF LAKE SUPERIOR
WHERE CAA HAS BROUGHT 850 TEMPS BLO 10C AND SFC DEWPOINTS LINGERED
IN THE 50S F. CU...MOST PREVALENT OVER INLAND AREAS OF CNTRL UPR MI
AT 15Z SUPPORTED BY SFC DEWPOINTS ALSO IN MID TO UPPER 50S F IN WAKE
OF RECENT RAINFALL AND MOIST GROUND. FCST 850 TEMPS FROM 10-13C PER
12Z RUC/ETA SUPPORTS GOING TEMP FCST. NW TO N 950 GRADIENT WIND
AROUND 10 KNOTS WEAK ENOUGH WITH LAND/LK DLT/T NEAR 10C TO ALLOW LGT
LK BREEZE OFF OF LK MI AND BOOST NRLY FLOW INTO NORTH CNTRL UPR MI.
.MQT...NONE.
JLB
FXUS63 KAPX 171529 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1125 AM EDT SAT JUL 17 1999
RATHER WIDE LINE OF SHRA/EMBEDDED TSRA CONTINUES TO MOVE THROUGH
MOST OF NRN AND CENTRAL LOWER MI ALONG THE AHEAD OF A COLD FRONT.
PRECIP IS ALSO RECEIVING SUPPORT FROM THE RRQ OF AN UPPER LEVEL JET
MAX OVER ONTARIO AND DPVA ASSOCIATED WITH A VORT MAX MOVING TOWARD
SRN LOWER MI. MAIN CONCERN FOR THE AFTERNOON IS TIMING ENDING OF
PRECIP ACROSS MOST OF NRN LOWER AND THEN TIMING DECREASING CLOUDS
FAIRLY QUICKLY BEHIND THE FRONT.
STRENGTH OF THE ETA WITH RESPECT TO THE VORT MAX PANNED OUT WELL...
BUT TRACK DEPICTED BY THE NGM ACTUALLY VERIFIED BETTER THAN THE ETA.
RUC SUGGESTS A DECREASE IN UPPER SUPPORT ACROSS SW CWA LATE THIS
AFTERNOON AS THE VORT MAX MOVES THROUGH SRN LOWER MI. THETA E RIDGE
FOLLOWS SUITE...WITH THE AXIS OF HIGHEST THETA E MOVING TO SE LOWER
MI BY 21Z PER LATEST RUC RUN. AHEAD OF THE FRONT...INSTABILITY WILL
REMAIN HIGH...WITH CAPES FROM APX MODIFIED SOUNDING AROUND 2700 J/KG
AND LI'S OF -7. HOWEVER...SVR WX WILL LIKELY NOT BE A PROBLEM FOR
THE AFTERNOON FOR SE CWA WITH LITTLE IF ANY SUN TO WORK WITH AND A
NEAR TOTALLY SATURATED COLUMN TO INHIBIT NEGATIVE BUOYANCE AND
THUS...DOWNBURST POTENTIAL. FREEZING LEVEL WILL REMAIN HIGH AS
WELL...SO LITTLE THREAT FOR LARGE HAIL REACHING THE GROUND.
WILL UPDATE ALL ZONES FOR VARIOUS REASONS. ERN UPR HAS GONE MOSTLY
SUNNY AND WILL REMAIN SO THROUGH THE AFTERNOON AS DRIER MORE STABLE
AIR FILTERS INTO THE REGION BEHIND THE FRONT. WILL DECREASE CLOUDS
OVER FAR NRN LOWER MI WERE PRECIP HAS STOPPED AND CLOUDS ARE
BEGINNING TO BREAK UP. AREAS FROM GLR TO TVC TO MBL WILL SEE PRECIP
END DURING EARLY AFTERNOON...APN TO HTL BY MID AFTERNOON AND THEN
FINALLY ACROSS SE SECTIONS OF THE CWA BY LATE AFTERNOON. CLOUDS WILL
RAPIDLY DECREASE ONCE PRECIP ENDS...WITH GOOD DRYING AT LOW/MID
LEVELS TAKING PLACE DIRECTLY BEHIND THE FRONT.
.APX...NONE.
EME
FXUS63 KDTX 171345 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1005 AM EDT SAT JUL 17 1999
12Z RUC SHOWS SHORT WAVE OVER CENTRAL GA WITH RIDGE EXTENDING ACROSS THE
MIDLANDS TO CENTRAL NC. CONVECTION OVER CENTRAL/SRN GA WEAKENING WHILE
MAKING VERY LITTLE PROGRESS EASTWARD. DEBRIS CLOUDS OVER CSRA WILL TEND
TO HOLD TEMPS DOWN.
SHORT WAVE FORECAST TO SLOWLY MOVE EASTWARD THIS AFTERNOON. PLAN TO
INCREASE CLOUD COVER ACROSS THE CSRA AND LOWER TEMPS ONE CATEGORY.
POPS LOOK OKAY. REST OF FORECAST ON TRACK.
.CAE...NONE.
LM
FXUS62 KCHS 171357 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
243 AM EDT SAT JUL 17 1999
RUC INDICATES WEAKNESS IN H5 RIDGE OVR CWA. VORT ALONG GA/SC BORDER OVR
CSRA ATTM IS FCST TO MOVE TO THE CST TDY. ETA FCSTS NVA TO MOVE INTO
MOST OF THE UPSTATE AND NRN COUNTIES OF CWA TDY. DON'T THINK TOO MUCH IN
THE WAY OF CONV WIL DEV. ETA SHOWS DECENT VORT MOVING THRU THE AREA ON
SUN...COULD BE ENUF TO TRIGGER SCT CONVECTION WITH LI'S -3 TO -5 OVR CWA
TDY AND SUN. H5 CLOSED LOW MOVING INTO FL IS PUSHING THE RIDGE A LITTLE
FURTHER N OVR THE AREA BUT MODELS ARE TRENDING TOWARDS RE-ESTABLISHING
RIDGE OVR MS VLY WITH WEAKNESS OVER THE AREA FOR THE NEXT COUPLE OF
DAYS. BERMUDA HIGH TRYING TO GET HEAT PUMP STARTED, BUT WITH SO MANY
WEAKNESES IN THE RIDGE WE CANT ESTABLISH DECENT SW FLOW. WILL CONT TO
UNDERCUT GUIDANCE BY A DEGREE OR TWO WITH HIGHER POPS IN SRN PORTIONS OF
THE FCST AREA. A LOT OF CONV DEBRIS ATTM BUT THINK CLOUDS WILL THIN OVR
NRN PORTION OF THE CWA.
PRELIM CCF
CAE BB 90/71/91/71 102
AGS BB 89/69/91/70 323
.CAE...NONE.
BARLOW
FXUS62 KCHS 170626 sc
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1015 AM MDT SAT JUL 17 1999
THE 16Z SURFACE ANALYSIS HAD BROAD LOW PRESSURE OVER WY WITH A WARM
FRONT INTO THE NORTHERN PORTIONS OF NE. WATER VAPOUR SHOWED
SHORTWAVE OF INTEREST OVER THE BLACK HILLS. THIS FORCING IN
CONJUNCTION WITH THETA-E ADVECTION OVER THE WARM FRONT IS SUPPORTING
SHRA/TSRA OVER NORTHWEST SD. 1KM VISIBLE LOOP SHOWS CLEARING EDGING
NORTHEAST AS PRESSURE FALLS SUGGEST FRONT LIFTING INTO SOUTHWEST SD
TODAY. CONCERNS THIS MORNING ARE TEMPERATURES AND PRECIPITATION.
THE 12Z RUC/ETA INITIALIZED ALRIGHT. THEY BOTH BRING THE WARM FRONT
INTO SOUTHWEST SD IN RESPONSE TO BROAD SOUTHWEST FLOW AHEAD OF
STRONG UPPER SYSTEM OVER THE PACIFIC NORTHWEST. DRY PUNCH ALOFT
QUITE PRONOUNCED. THE BIG QUESTION IS WILL WE BE ABLE TO MIX OUT THE
LOW LEVEL MOISTURE TO GET SOME SUN. CURRENT SATELLITE IMAGERY
SUPPORTS THIS ALONG AND SOUTH OF THE FRONT. HENCE...I/D EXPECT SOME
SUN ALONG I-90 ON SOUTH TODAY. LOTS OF CLOUDS WILL PERSIST IN THE
NORTH AS PRECIPITATION ENDS. THIS WILL OCCUR BY MID-AFTERNOON AS
BEST QG-FORCING MOVES INTO KABR CWA. 850-700MB THETA-E RIDGE WILL
POINT INTO THE HILLS THIS AFTERNOON. HENCE...ANOTHER CHANCE OF
PRECIPITATION WARRANTED AS FRONT LIFTS NORTH.
WILL BASE UPDATE FOR TEMPERATURES ON EXPECTED FRONTAL POSITION.
.UNR...NONE.
HELGESON
FXUS63 KFSD 171504 sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
305 PM CDT SAT JUL 17 1999
FORECAST CHALLENGES -- POPS AND POSSIBLE HEAVY RAINFALL TONIGHT.
SYNOPSIS -- LATEST KOAX 88D REFLECTIVITY LOOP SHOWED SHOWERS
INCREASING IN AREAL COVERAGE ACROSS ERN NEB WITH THE KOAX VWP AND
FBY WIND PROFILER SHOWING INCREASING WARM ADVECTION IN THE 850-750MB
LAYER. MEANWHILE...18Z SURFACE ANALYSIS SHOWED A WARM FRONT
EXTENDING FROM N OF HLC EWD TO N OF TOP AND THRU THE MKC METRO WITH
+70 DEGREE DEWPOINTS POOLED ALONG AND TO THE N OF THIS BOUNDARY.
FORECAST -- LOW-LEVEL MOIST/THERMAL ADVECTION PROGGED BY ETA/NGM TO
RAPIDLY INCREASE ACROSS ERN NEB TONIGHT AS SURFACE WARM FRONT PULLS
N. CONVECTIVE DEVELOPMENT WILL BE AIDED BY 35KT LOW-LEVEL JET WITH A
FAIRLY HIGH PRECIPITATION EFFICIENCY EXPECTED AS PWS ARE FORECAST TO
INCREASE TO AROUND 2 INCHES WITH ETA/RUC FORECAST SOUNDING WARM
CLOUD DEPTHS OF 3KM. THEREFORE...WE WILL ISSUE A FLASH FLOOD WATCH
TONIGHT FOR NORTHEAST AND PARTS OF EAST CENTRAL NEBRASKA...AS WELL
AS SOME WRN IA COUNTIES. ALTHOUGH MOST COUNTIES IN THE WATCH AREA
HAVE FFG VALUES OF AROUND 2 INCHES...EXCESSIVE RAINFALL POTENTIAL IS
THERE. OTHERWISE...SHOULD BE A MILD NIGHT WITH TEMPERATURES AROUND
70 OR THE LOWER 70S.
CONVECTION WILL LIKELY BE LINGERING IN ERN ZONES TOMORROW MORNING
WITH CONSIDERABLE CLOUDS. SURFACE FRONT IS FORECAST TO BE NEAR
THE NEB-SD BORDER WITH SOME UNCERTAINTY AS TO HOW MUCH FARTHER N IT
WILL LIFT DURING THE DAY. THE ETA IS FORECASTING SBCAPES OF
2500-3500 J/KG ACROSS NWRN ZONES BY LATE AFTERNOON WITH ONLY MINIMAL
CIN. THEREFORE...DUE TO UNCERTAINTY OF FRONTAL AND/OR OUTFLOW
BOUNDARY LOCATIONS...WE WILL INSERT CHANCE POPS IN THESE AREAS.
SUNDAY NIGHT...ETA TRIES TO DEVELOP AN MCS OVER SD WITH SRN EXTENT
OF PRECIP POSSIBLY AFFECTING FAR NWRN ZONES. AGAIN...SLIGHT CHANCE
POPS NW. ON MONDAY...WE AGREE WITH MORE OF THE AVN FRONTAL POSITION
AND WILL NOT MENTION ANY POPS. GUIDANCE TEMPERATURES GENERALLY
ACCEPTED.
.OMA...FLASH FLOOD WATCH THROUGH TONIGHT NEZ011-012-015>018-030>034-
042>045-051>053 AND IAZ043-055-056-069
MEAD
FXUS63 KGID 171939 ne
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
131 PM EDT SAT JUL 17 1999
MID AND UPPER LEVEL MOISTURE MOVING OVER FORECAST AREA TODAY. MOST
SFC DEWPOINTS AROUND 70. NEARBY MODIFIED MORNING SOUNDINGS SHOW LI
VCNTY -5 WITH CAPE ABOUT 2000 GSO AND 2640 FFC. RUC OLD. ETA SHOWS
WEAK UPPER LEVEL DIVERGENCE AND POSITIVE VORTICITY(LITTLE IF ANY
ADVECTION) WITH A VERY WEAK SHORTWAVE TROF MOVING SLOWLY IN WEAK
FLOW. THIS IS CAUSING SOME LIFT AND ETA SHOWS UVV AND WEAK Q-
FORCING. SHWRS DEVELOPING ACROSS CWA AND UNTIL SFC COOLS LATER THIS
EVE WILL KEEP SHOWERS AND TSTMS IN ZONES. EXPECT DECREASING
SHOWERS/CLOUDS BY LATE EVENING WITH COOLING. MOISTURE AND WEAK
DYNAMICS WILL ALSO BE SLIDING SLOWLY EAST.
EXPECT SUNDAY AND MONDAY WILL BE MORE STABLE...DRYER AND LESS CLOUDY
AFTER PATCHY MORNING FOG WITH HI TEMPS AROUND GUIDANCE VALUES. ETA
DOES SHOW A WEAK UPPER LEVEL JET (40 KTS) OVER MTNS MON BUT WILL NOT
MENTION POPS DUE TO THIS FEATURE ATTM.
AVL 65/86/66/89 311
CLT 72/91/73/92 111
GSP 68/91/71/92 111
.GSP...NONE.
RB
FXUS62 KCAE 171405 sc