SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO
153 PM MDT WED APR 28 1999
CONCERNS INCLUDE THE POTENTIAL FOR HEAVY RAIN...AND SNOW
ACCUMULATIONS OVER THE HIGHER PASSES AND PEAKS. MODELS IN GOOD
AGREEMENT MOVING CLOSED UPPER LOW TO SOUTHERN NV THIS EVENING...
WITH THE LOW MEANDERING AROUND SRN NV/NW AZ/SW UT THROUGH 30/06Z.
THIS SYSTEM IS THEN EXPECTED TO WEAKEN AND BEGIN MOVING ON
SATURDAY.
STRONG SOUTH TO SOUTHEAST WINDS THROUGH A DEEP LAYER...
AND 80+ RH UP TO AROUND 450 MB ARE EXPECTED TONIGHT. WHILE H7
TEMPS REMAIN AROUND +2 DEG C. RUC SHOWS A WEAK SHORTWAVE MOVING
ACROSS THE AREA THIS EVENING AND SHOULD SEE SOME THUNDERSTORMS.
OTHERWISE THERE WILL BE PERIODS OF RAIN TONIGHT OVER THE EASTERN
MOUNTAINS AND ADJACENT PLAINS...WITH SCATTERED TO LIKELY CHANCES
OVER THE FAR EASTERN PLAINS. PW VALUES TONIGHT ARE EXPECTED TO
RANGE FROM ABOUT .8 TO 1 INCH OVER THE SOUTHEST PLAINS. ETA PRECIP
FORECAST FOR THE 12HR PERIOD OVERNIGHT...SHOWS 1 TO 1.5 INCHES OVER
PORTIONS OF THE SOUTHEAST PLAINS. WILL MENTION HEAVY RAIN POSSIBLE
IN ZONES ADJACENT TO THE MOUNTAINS. PLUGGING NUMBERS INTO THE
SNOW MODEL GIVES SOME SIGNIFICANT AMOUNTS TONIGHT...BUT SNOW LEVELS
SHOULD BE HIGH...WITH THE SIGNIFICANT AMOUNTS FALLING ABOVE 10000
FT. WILL ISSUE WINTER STORM WARNING FOR THE SOUTHWEST MOUNTAINS FOR
TONIGHT. FOR THE EASTERN MOUNTAINS WILL ISSUE WINTER STORM WARNING
FOR TONIGHT AND THURSDAY FOR ZONES 65/66/67/70 ABOVE 10000 FEET.
TOMORROW THE MOISTURE LAYER DECREASES WITH 80+ RH UP TO AROUND H6...
BUT SOUTHEAST WINDS AT H7 ARE STILL EXPECTED TO BE 30 TO 35 KTS...
AND THE POTENTIAL FOR PREICP REMAINS HIGH. THURSDAY NIGHT THE
MOISTURE LAYER DEEPENS AGAIN WITH HEAVY RAIN AGAIN POSSIBLE...
ESPECIALLY ALONG AND ADJACENT TO THE EASTERN MOUNTAINS.
ETA FORECAST PRECIP AMOUNTS FOR OVERNIGHT THURSDAY SHOWING
.5 TO 1 INCH OVER PORTIONS OF THE SOUTHEAST PLAINS. SIGNIFICANT
ACCUMULATIONS OF SNOW OVER THE HIGHER ELEVATIONS COULD AGAIN BE A
PROBLEM...BUT NOT TOO SURE AT THIS TIME.
ON FRIDAY THE SYSTEM WILL CONTINUE TO AFFECT THE FORECAST AREA...
BRINGING SCATTERED SHOWERS AND THUNDERSTORMS.
IN THE EXTENDED...ON SATURDAY THE LOW IS EXPECTED TO WEAKEN AND
BECOME AN OPEN WAVE WITH THE MAIN DYNAMICS MOVING ACROSS CENTRAL OR
SOUTHERN NM AND THEN MOVES INTO THE CENTRAL PLAINS SUNDAY.
.PUB...WINTER STORM WARNING TONIGHT ABOVE 10000 FT...ZNS 60/61
WINTER STORM WARNING TONIGHT AND THURSDAY ABOVE 10000 FT...ZNS
65/66/67/70
FXUS65 KGJT 281906 co
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
255 AM EDT WED APR 28 1999
AS HAS BEEN THE CASE FOR MUCH OF THIS WEEK...NGM/ETA/NGM ALL IN
GOOD AGREEMENT WITH DEVELOPMENT OF 500 MB PATTERN NEXT 42 HOURS.
THEY SHOW A CLASSIC OMEGA BLOCK SETTING UP...WITH THE AVN GOING SO
FAR AS TO DROP A CLOSED LOW OFF THE SE COAST IN 72 HOURS.
05 UTC SFC ANALYSIS/RADAR IMAGERY/03 UTC RUC ALL INDICATE A WEAK
QUASI-STATIONARY BOUNDARY ACROSS WESTERN PORTIONS OF OUR FORECAST
AREA. THERE HAS BEEN ENOUGH LOW-LEVEL MOISTURE FLUX CONVERGENCE IN
THIS HIGH THETA-E AIR TO TRIGGER PESKY RENEGADE STORMS. THEY ARE
DIMINISHING SOMEWHAT NOW...BUT SHOULD RE-DEVELOP THIS AFTERNOON AS
THIS BOUNDARY MEANDERS. CURRENT ZONES AND CWF LOOK OKAY FOR TODAY.
LOOKING AHEAD TO THURSDAY...A STRONG BACKDOOR COLD FRONT (CURRENTLY
ACROSS THE CAROLINAS) WILL MOVE INTO THE FORECAST AREA THURSDAY
AFTERNOON. THIS SHOULD BRING AN EVEN BETTER CHANCE FOR MUCH NEEDED
RAIN ON THURSDAY AFTERNOON TO THE BIG BEND AND SOUTH
GEORGIA...DESPITE FWC/FAN NUMBERS. WHILE I AGREE WITH MIA 40
PERCENT POPS FOR BIG BEND ZONES ON THURSDAY...DON'T KNOW ABOUT THE
CLEARING LATE WORDING...AS IT LOOKS LIKE THE BEST CHANCE FOR RAIN
WILL BE LATER IN THE AFTERNOON.
FOURNIER
NNNN
FXUS62 KTBW 280656 fl
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1020 AM EDT WED APR 28 1999
WEDGE ASSOCIATED FRONT ALONG SC BORDER WILL MOVE SLOWLY SOUTHEAST.
WILL REALLY BE WITH US A FEW MORE DAYS. WEAK TROF BOUNDARY FROM
WWEST TENNESSE TO NEAR PNS. SEE SOME REFLECTION OF THIS IN VISIBLE
SATELLITE DATA AND ACTIVITY FIRING IN SOUTHEAST ALABAMA. RUC BEST
DEPICITION OF THIS. 12Z UPPER AIRT ANALYSIS SHOWS OVER MISSISSIPPI
FROM 850+ THAT SHOULD MOVE INTO WESTERN GA BY 18Z. WHILE THIS
ACTIVITTY SHOULD NOT BE SEVERE, WILL MONITOR. IN NORTHWEWST
VORTICITY OVER OHIO VALLEY WILL ROTATE INTO NORTHWEWST GA BY 18Z.
THIS PLUS FRONT WILL FOCUS AVTIVITY THERE. WILL RAISE POPS A LITTLE
WEST. OTHERWISE CURRENT POPS LOOK OK.
TEMPERATURES. CLOUD DEPENDENT. WILL RAISE WEST AND LOWE REAST A
LITTLE.
.ATL....NONE.
FXUS72 KFFC 280816 ga
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
939 AM EST WED APR 28 1999
PER SATELLITE AND RADAR TRENDS THIS AM... WILL NEED TO UPDATE N THIRD
OF IN CWA ALONG W S MI ZONES TO ACCOUNT FOR OBSERVED DRYING TREND.
QUITE A FEW BREAKS HAD DVLPD AS WELL BUT LOCAL CU RULE ALONG
WITH LINGERING LOW LVL MOISTURE AND WET GROUND ACRS N IN WOULD
SUGGEST SOME CU WILL DVLP BY LATE AM. HWVR RUC2 FM BOTH 9 AND 12Z
CONT TO INDICATE SIGNIFICANT DRYING TREND THRU THE COLUMN FM NE TO SW
THRU THIS PM AND WILL INDICATE SUCH IN MORNING UPDATE. XPC TEMPS MAY
RECOVER MORE SO THEN GIVEN IN CURRENT ZONES MORE LIKE GOING FWC
GUIDANCE FM LAST NIGHT.
.IWX...NONE.
TEH
FXUS73 KIND 280817 in
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1130 AM CDT WED APR 28 1999
PESKY MATURE LOW OVER STL...GOING NOWHERE FAST. SHOULD CONTINUE TO
VERY SLOWLY MOVE AWAY FROM CWA...INFLUENCING WX LESS AND LESS. DRY
AIR HAS ADVECTED INTO NRN IA WITH NE WINDS ON BACK SIDE OF LOW.
SATELLITE TRENDS AND 12Z RUC DATA BRING CLEARING TO AROUND HIGHWAY 30
BY LATE THIS AFTERNOON. CURRENT ZONES HAD THAT WELL IN HAND. MADE
ONLY MINOR UPDATES TO REMOVE MORNING WORDING AND TO TIGHTEN UP MAX
TEMPS RANGES.
.DSM...NONE
SEARCY
FXUS63 KDMX 280810 ia
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
340 PM EDT WED APR 28 1999
LOW LEVEL CONVERGENCE CONTINUES TO FEED THE SHOWER ACTIVITY OVER THE
SOUTHWEST PORTION OF THE FORECAST AREA. RUC SHOWS THIS AREA
REMAINING NEAR OR TO THE SOUTHWEST OF THAT PORTION OF THE FORECAST
AREA. AS A RESULT WILL KEEP THE CHANCE OF PRECIPITATION IN THE
SOUTH PORTION OF THE FORECAST AREA TONIGHT. AS THE LOW PASSES TO
THE SOUTH THE CHANCE WILL BE HELD IN THE SOUTHERN PORTION OF THE
FORECAST AREA THURSDAY.
EASTERLY FLOW SHOULD BE STRONG ENOUGH THROUGH THE NEXT SEVERAL
FORECAST PERIODS THAT THE MINIMUM TEMPERATURES WILL NOT BE AS LOW AS
MOS IS TRYING TO TAKE THEM. THIS FAIRLY STRONG EASTERLY FLOW WILL
ALSO KEEP THINGS COOL IN THE SOUTHERN MOUNTAINS.
OTHERWISE KEPT WITH THE GUIDANCE TRANDS.
.CRW...
WV...NONE.
VA...NONE.
KY...NONE.
OH...NONE.
.END / AAR
FXUS63 KJKL 281854 ky
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
955 AM EDT WED APR 28 1999
PRECIPITATION LINES UP WELL WITH LOW LEVEL MOISTURE CONVERGENCE
FIELD. RUC MODEL SHOWS THE LOW LEVEL MOISTURE CONVERGENCE SLIDING TO
THE SOUTHWEST PORTION OF OUR AREA THIS AFTERNOON TO A LINE FROM NEAR
HUNTINGTON TO CHARLESTON THEN SOUTH ALONG THE WESTERN SLOPES INTO
SOUTHWEST VIRGINIA. WITH THIS IN MIND WILL LOWER PROBABILITIES IN
THE NORTH TO 40 PERCENT THIS AFTERNOON AND WILL ADD A CHANCE OF A
THUNDERSTORM IN THE SOUTHWEST PORTION OF THE AREA.
OTHERWISE NO CHANGES TO THE FORECAST.
.CRW...
WV...NONE.
VA...NONE.
KY...NONE.
OH...NONE.
.END / AAR
NNNN
FXUS63 KJKL 281254 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
855 AM EDT WED APR 28 1999
UPDATING TO DROP DENSE FOG ADVISORY. QUICK LOOK AT 09Z RUC AND LAST
NIGHT/S MODEL RUN OF ETA INDICATE A SE FLOW SETTING UP IN THE LOW
LEVELS ARS FAR ERN FA...WHICH MAY HAMPER SHOWERS SOMEWHAT INTO GETTING
FULL BLOWN THIS AFTN. BEST UVM WILL ARRIVE LATE THIS AFTN IN SW CWA.
FOR NOW WILL LEAVE MIDNIGHT SHIFT FORECAST ALONE AND EVALUATE MORE
MODEL DATE...ETC BEFORE MAKING A DECISION FOR THE AFTN PERIOD.
.JKL...NONE.
WHP
NNNN
FXUS63 KJKL 280850 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
1010 AM EDT WED APR 28 1999
MODELS SHOW NRN SYSTEM INFLUENCING FA MORE AND HELPING TO CHG FLOW
TO MORE N ALOFT WHICH HELPS TO PUSH PRECIP AREA JUST A LITTLE
FARTHER S. THIS IS WELL DEPICTED ON RUC AND MESOETA AS THEY BOTH
THIN CLDS ACRS THE N DURG THE DAY. WL LOWER POPS BACK TO CHC OVR THE
SRN PART AREA AND REDUCE CLD COVER O PARTLY SUNNY IN THE N.
LOOKING AT BUFR DATA SHOWS STRATUS DEVELOPING ACRS THE AREA TNGT
ARND MIDN AND WITH E FLOW THAT LOOKS GOOD SO THE MSTLY CLDY FCST FOR
TNGT STILL WORKS.
TEMPS WL ONLY NEED MINOR ADJUSTMENT.
.LWX...NONE.
JAB
FXUS61 KLWX 280637 md
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1125 AM EDT WED APR 28 1999
ONLY SOME MINOR ADJUSTMENTS TO THE PREVIOUS FORECAST. SATELLITE
TRENDS SUGGEST THAT THE MID LEVEL CLOUDINESS ACROSS SW PORTIONS OF
MY AREA WILL CONTINUE TO PUSH SW. LATEST RUC MODEL CONFIRMS THIS.
GUSTY WINDS REPORTED AT ALL LOCATIONS AND WILL LEAVE THIS IN
FORECAST. HIGH TEMPERATURES ON TRACK...WITH STRONG SUNSHINE
EXPECTED AT ALL AREAS THIS AFTERNOON.
ZONES WILL BE OUT BY 1535Z.
.GRR...NONE.
MJS
FXUS63 KAPX 281511 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
400 AM EDT WED APR 28 1999
OMEGA BLOCK WILL DOMINATE NORTH AMERICA THROUGH THE WEEKEND. UPPER
MICHIGAN WILL BE UNDER OR JUST EAST OF UPPER HIGH THROUGH DAY 5...
AND DRY WEATHER WILL CONTINUE.
WATER VAPOR SATELLITE IMAGERY AND 300MB HEIGHT ANALYSIS OF 06Z RUC
SHOW THE REMNANTS OF OLD CUT OFF LOW THAT HAD RESIDED OVER SOUTHWEST
CONUS LAST WEEKEND HAVE PROGRESSED EAST AS A CUT OFF LOW NOW CENTERED
OVER WESTERN ILLINOIS. THE UPPER TROF JUST NORTH OF THIS CUT OFF
YESTERDAY HAS SPED NORTH TO AROUND 60N AND SHEARED AWAY TO NEARLY
NOTHING. THE ILLINOIS CUT OFF WILL SLOWLY DRIFT SOUTHEAST TODAY...
AND THEN STALL OVER SOUTHEAST CONUS. THIS LEAVES THE UPPER HIGH
CENTERED OVER LAKE SUPERIOR REGION IN A POSITION TO BUILD AND DRIFT
SLOWLY WEST THROUGH THURSDAY... ESPECIALLY SINCE AN UPPER TROF NOW
OVER WEST COAST IS PROGGED TO DROP INTO THE SOUTHWEST AND DEVELOP
INTO YET ANOTHER CUT OFF LATER TODAY. THIS CUT OFF WILL HELP BUILD
HEIGHTS OVER CENTRAL NORTH AMERICA INTO THE WEEKEND. BUILDING
HEIGHTS OVER FORECAST AREA WILL PROVIDE CLEAR SKIES.
AT THE SURFACE... BROAD HIGH PRESSURE OVER ONTARIO AND QUEBEC WILL
PERSIST THROUGH FRIDAY. NORTHEAST BOUNDARY LAYER FLOW INTO THE
FORECAST AREA WILL CONTINUE. NGM SURFACE DEWPOINTS ARE DRIER THAN
ETA ONCE AGAIN AND ARE PREFERRED.... BASED ON VERIFICATION AGAINST
06Z METARS AND ON PAST PERFORMANCE DURING WHICH ETA SURFACE
DEWPOINT FIELD HAS SIMPLY BEEN TOO MOIST AND CONSISTENTLY WRONG FOR
A WEEK NOW. NGM SUGGESTS DEWPOINTS IN THE 20S F THROUGH 48 HOURS.
MODELS SHOW 850MB TEMPERATURES AROUND 2-4C OVER UPPER MICHIGAN
TODAY... AND 4-6C THURSDAY. DRY ADIABATIC MIXING OF 850MB
TEMPERATURES TO SURFACE IMPLIES HIGHS TOPPING OUT AT 60-65F TODAY
FOR AREAS INLAND FROM LAKE INFLUENCE. FOR TOMORROW... HIGHS UP TO
65-70F INLAND.
IN THE EXTENDED RANGE... MRF AND ECMF SHOW QUITE GOOD AGREEMENT ALL
THE WAY OUT TO 12Z SUN. AT 500MB BOTH MODELS HAVE THE OMEGA
UNCHANGED UNTIL SUNDAY MORNING WHEN THE SOUTHWEST CONUS LOW BEGINS
TO LIFT NORTHEAST. STILL... THIS CHANGE IS JUST BEGINNING ON SUNDAY
AND THE U.P. WILL BE SUNNY AND WARM THROUGH THE WEEKEND. AT THE
SURFACE... THE MODELS AGREE THAT THE HIGH PRESSURE CENTERED OVER
SOUTHEAST CANADA WILL DROP OVER OHIO VALLEY AS A WEAK LOW DEVELOPS
IN HUDSON BAY. RESULTING SOUTHWEST BOUNDARY LAYER FLOW ON SUNDAY
BRINGS WARM ADVECTION... MRF HAS 850MB TEMPERATURES AROUND 10C OVER
FORECAST AREA SUNDAY WHICH SHOULD BE FOR HIGHS AROUND 75F.
.MQT...NONE.
ES
NNNN
FXUS63 KAPX 280752 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1010 AM CDT WED APR 28 1999
A NICE AFTERNOON IS IN STORE FOR THE CWA AS HIGH PRESSURE
STRENGTHENS OVER THE REGION. MORNING RAOBS SHOWING COOLER LOW LEVEL
AIR SPREADING IN FROM THE EAST. COOLEST HIGHS THIS AFTERNOON
EXPECTED OVER THE WI CWA. TAKING THE 850 MB TEMP DRY ADIABATICALLY
TO THE SURFACE WOULD YIELD HIGHS FROM THE LOWER 60S IN WI TO THE
MIDDLE 60S OVER WEST CENTRAL MN. WILL ADJUST AFTERNOON HIGHS A
LITTLE. WILL ALSO GO SUNNY AS THE CS IS DISSIPATING NICELY. RAOBS
AND PROFILER DATA WOULD SUGGEST A LITTLE STRONGER SURFACE WIND FOR
THIS AFTERNOON WITH THE DRY ADIABATIC LAPSE RATE. WINDS IN THE
BOUNDARY LAYER AND ABOVE MOSTLY IN THE 20 KNOT RANGE. 12Z RUC
1000-850 MB WIND PROG SHOWS MOST LOCATIONS THIS AFTERNOON SEEING 15
TO 20 KNOT SUSTAINED WINDS. HENCE...WILL INDICATE BREEZY AS WELL FOR
THE AFTERNOON.
.MPX...NONE.
HILTBRAND
FXUS63 KDLH 281459 mn
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE WILMINGTON NC
1000 AM EDT WED APR 28 1999
WV IMGRY SHOWS WK VORT MVG INTO CAROLINA MTNS AS DEPICTED BY 03Z
MESO-ETA & 12Z RUC2. AREA RDRS SHOW SCT RW AHD OF VORT MVG E ACRS
ERN CAROLINAS. MOST OF THIS SHUD BE GONE BY NOON.
CSTL 12Z RAOBS SHOWED A MARG UNSTABLE AMS IN PLACE...MORESO OVR SC
CWA. K VALUES RANGED FM UPR 20S TO MID 30S & TT NUMBERS WERE 45-50.
MAIN PROB THIS AFTN WL BE LACK OF HTG TO HELP INIT CONVECTION AS CLD
DECK LOOKS FAIRLY SOLID ALL THE WAY BACK TO ERN AL. WL KEEP THE
GOING CHC POPS FOR THE AFTN.
HI BUSTABILITY W/ TEMPS THIS AFTN...ESPLY IF ANY BINOVC DEVELOP. LCL
SCHEMES GOING BLO CURR FCSTS INL & W/ TEMPS ONLY IN LWR/MID 50S AT
13Z WL FOLLOW. CSTL TEMPS SEEM OKAY.
CWF: HV UPDATED CWF TO UP WINDS ALG NC CST THIS MRNG. MSAS ANALYSES
SHOW LO PRES FRMG OFF THE SC/GA CST. MESO & RUC PTG TWD THE LO MVG
INTO SC WTRS PRODUCING VRB WINDS THIS AFTN. ATTM AM LEANING TWD JUST
BRINGING WINDS ARND TO THE N. WL STAY BLO SCA CRIT BUT MAINTAIN
GUSTY AS THE GRAD SHUD RELAX AS THE LO APRCHS.
***UPON LOOKING AT LATEST BUOY REPS...WILL RAISE SCA FOR NC WTRS***
.ILM...SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET.
LGE
FXUS62 KILM 281402 nc
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1100 AM CDT WED APR 28 1999
LATEST VISIBLE SATELLITE IMAGERY CONTINUING TO SHOW LOW CLOUDS
WRAPPING AROUND LOW PRESSURE SYSTEM TO OUR NORTHEAST. 12Z RUC KEEPS
75 PERCENT OR BETTER RH IN LOWEST LEVELS ACROSS NORTHEAST ZONES ALL
DAY AND LATEST FWC MOS ALSO SUGGESTS CLOUDS WILL LINGER. RUC
SHOWING SURFACE LOW DRIFTING MORE SOUTHEASTERLY INSTEAD OF EAST OVER
TIME WHICH WOULD ALSO LEAD TO MORE OF THE WRAP AROUND CLOUDS
LINGERING TODAY. THEREFORE...HAVE ALREADY UPDATED ZONES TO REFLECT
CURRENT TRENDS AND LOWERED TEMPS IN THE NORTHEAST.
HOWIESON
FCSTID = 44
.TUL...
AR...NONE.
OK...NONE.
FXUS64 KTSA 280904 ok
AREA FORECAST DISCUSSION FOR CENTRAL/NORTH CENTRAL/NORTHEAST SD
AND FOR BIG STONE AND TRAVERSE COUNTIES OF MN
NATIONAL WEATHER SERVICE ABERDEEN SD
940 AM CDT WED APR 28 1999
VIS LOOP SHOWS EXTENSIVE LOW CLOUDS OVER W AND SW COUNTIES...INCL MBG
AND PIR AREAS. EARLIER THOUGHTS THAT FWC TEMPS FOR PIR WERE TOO LOW MAY
NOT BE TOO FAR OFF THE MARK AFTER ALL. FWC HOLDS CLOUDINESS IN AND MAX
TEMP DOWN TO AROUND 60 THERE. STILL FEEL THIS IS TOO COOL FOR PIR
AREA...WHICH JUMPED TO 68 ON TUE. DROPPED HIGHS A FEW DEGREES FROM
EARLIER FCST...TO MID 60S AROUND PIR...AND LOWER 60S AROUND MBG. KEPT
CLOUDS IN THRU THE AM IN WESTERN COUNTIES...BUT STILL XPCT SOME BREAKS
IN CLDS BY AFTN. CHECK OF LATEST RUC STILL SHOWS SLIGHTLY STRONGER
GRADIENT IN WESTERN COUNTIES THIS AFTERNOON...SO NO CHANGE TO WIND FCST
FOR TODAY. NO CHANGES TO EASTERN COUNTIES...FCST APPEARS ON TRACK
THERE.
.ABR...NONE.
LORENS
FXUS63 KUNR 280922 sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
748 PM EDT WED APR 28 1999
SATELITTE SHOWS UPPR LOW OVR IL/MO DRIFTING EVER SO SLOWLY SOUTH.
GOOD DIFLUENT PATTERN ACROSS KY/SO IN/MID-TN (INCLUDING THE PLATEAU).
RUC MODEL SHOWS THIS DIFLUENT PATTERN WEAKENING OVERNIGHT. BEST
CONVECTION OVR THE CWA HAS BEEN SCT AND ACROSS WESTERN HALF OF THE
CWA WHERE INSTABILITY IS BEST.
AT THE SURFACE...A STATIONARY FRONT WAS LOCATED BETWEEN TRI AND
TYS WITH A BACK DOOR COLD FRONT EVIDENT BY KHTX RADAR MOVING WEST
OVER SOUTHEAST TENNESSEE. THESE BOUNDARIES HAVE BEEN AIDING THE
INITIATION OF CONVECTION. HOWEVER...MODELS SHOW LOW LEVEL
STABILIZATION DURING THE NEXT 6 HOURS AND EXPECT CONVECTION TO
DIMINISH. ALSO...COLD AIR DRAINAGE INTO THE SOUTHERN TENNESSEE
VALLEY AND SOUTHWEST NORTH CAROLINA WILL LIMIT CONVECTION.
WOULD RECOMMEND DROPPING POPS TO 50-60 PERCENT FOR TONIGHT. GREATEST
THREAT FOR SEVERE WEATHER WILL BE ACROSS THE PLATEAU WHERE THE
BEST INSTABILITY RESIDES. MAIN THREAT WILL BE LARGE HAIL GIVEN THE
RELATIVELY LOW WBZ.
TEMPERATURE FORECAST LOOKS GOOD. HAVE A GOOD NIGHT.
DH
FXUS74 KMEG 282003 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1033 AM CDT WED APR 28 1999
SATELLITE IMAGERY SHOWING EXTENSIVE CLOUD COVER OVER NM IN ASSOCIATION
WITH THE NEXT STORM SYSTEM OVER NORTHERN CAL. WILL LEAVE PARTLY CLOUDY IN
FORECAST FOR ALL ZONES AS TRIGGER TEMPS FOR CONVECTIVE CU LOOK REACHABLE.
20 PERCENT FOR SHOWERS AND TSTMS STILL IN GOOD SHAPE AS SOUNDINGS SHOWING
REASONABLE CAPES WITH MAX TEMPS APPROACHING CONVECTIVE LEVELS. TEMPS IN
GOOD SHAPE EXCEPT FOR EASTERN BIG COUNTRY WHERE AN UPWARD ADJUSTMENT WILL
BE NEEDED. LATEST RUC MODEL INDICATING STRONGEST WINDS ACROSS EDWARDS
PLATEAU WHICH IS IN LINE WITH THE CURRENT FORECAST. 850 GRADIENT LOOKS
WEAKEST ACROSS THE EASTERN BIG COUNTRY SO WILL REMOVE GUSTS FROM THAT
AREA BUT LEAVE SUSTAINED FORECAST AS IS.
21
FXUS74 KFWD 281528 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
855 PM EDT WED APR 28 1999
BRIEFLY SEVERE CONVECTION OVER NW ZONES HAS RAPIDLY WEAKENED WHILE
MOVING SE OUT OF SURFACE THETA-E RIDGE TOWARD MESOHIGH CENTERED S
OF AQQ...WHICH RESULTED FROM CONVECTION EARLIER TODAY. MORE
PERSISTENT CONVECTION NOTED JUST N OF OUR GA ZONES...WHERE AN
APPROACHING BACK DOOR COLD FRONT AND SURFACE TROUGH INTERSECT. AT
00Z...COLD FRONT STRETCHED FROM THE AL/GA STATE LINE AND ARCED JUST
S OF A MCN-SAV LINE. MUCH COOLER AIR IS NOTED BEHIND THIS FRONT.
DRIER AIR NOTED N OF TROUGH....MEANING AREA OF FAVORABLE SURFACE
MOISTURE IS GETTING PINCHED OFF OVER OUR CWA. 00Z TLH SOUNDING ALSO
MUCH MORE STABLE AND DRY IN THE LOWER LEVELS.
AM NOT ENTIRELY SURE ABOUT WHAT TRIGGERED CONVECTION OVER PANHANDLE
THIS MORNING...SO THEREFORE CAN NOT CONCLUSIVELY SAY THIS WILL NOT
HAPPEN AGAIN. LATEST SURFACE DATA INDICATE STABLE MESOHIGH IS
DISSIPATING...AND 21Z RUC PROGS BACK DOOR FRONT TO MAKE IT WELL
INTO OUR NRN ZONES OVERNIGHT. CHANCE POPS JUSTIFIED AS MOIST
CONVERGENCE ALONG THIS BOUNDARY ALSO SPREADS S. GIVEN STRENGTH OF
SURFACE RIDGE ENTRENCHED OVER CAROLINAS AND CURRENT TRENDS...
BELIEVE RUC MAY BE UNDERFORECASTING PROGRESS OF FRONT...SO ALTHOUGH
BEST POPS BELONG IN GA AT THIS TIME...WILL ALSO KEEP CHANCE POPS
GOING IN FL ZONES.
SATELLITE AND A PEEK OUT THE WINDOW BOTH INDICATE WE MAY SEE SOME
PARTLY CLOUDY SKIES OVERNIGHT. THIS COMBINED WITH WET GROUND FROM
EARLIER RAINS AND EXPECTED LIGHT WINDS S OF FRONT MAY RESULT IN
PATCHY MORNING FOG...SO WILL MENTION THIS IN UPDATES. TEMPERATURES
LOOK ON TRACK. INPUT ALWAYS WELCOME.
TJT
FXUS62 KMLB 282008 fl
AREA FORECAST DISCUSSION...CORRECTED FOR CWF BREAK POINT
NATIONAL WEATHER SERVICE WILMINGTON NC
1000 PM EDT WED APR 28 1999
LIGHT RAIN AND DRIZZLE WILL CONTINUE OVER MOST OF THE CWA OVERNIGHT
AS SFC LOW CONTINUES TO DEVELOP OFF THE SC COAST. MOST OF THE
RAINFALL IS FOCUSED ALONG AN INVERTED SFC TROF WHICH EXTENDS FROM
THE SFC LOW NORTHWARD OVER BRUNSWICK COUNTY AT 01Z. ADDITIONAL
ENHANCEMENT IS BEING PROVIDED BY H8 FRONT WHICH LAYS ACROSS NE SC
PER 00Z ANALYSIS. RADAR TRENDS INDICATE THIS AREA OF PRECIP WILL
SPREAD VERY SLOWLY NORTH OVERNIGHT. CLOUDS WILL KEEP DIURNAL CHANGE
IN TEMPS IN CHECK...ON THE ORDER OF 5 DEGREES OR SO. CURRENT ZFP ON
TRACK ALTHOUGH WILL TWEAK POPS BASED ON CURRENT RADAR SCOPE.
CWF...PRES GRADIENT SET UP OVER ILM WATERS HAS PRODUCED SUSTAINED
30+ KTS AT FPSN7 LAST FEW HOURS. SOME OF THIS CAN BE ATTRIBUTED TO
ONGOING CONVECTION. BIGGEST CONCERN IS THE RATE OF INTENSIFICATION
OF SFC LOW AND EXPECTED ONSET OF GALES. RUCII QUICKER IN DEVELOPING
THE SYSTEM THAN THE ETA OVER NEXT 12 HOURS...ALTHOUGH SAFE TO SAY
THAT MOST DEVELOPMENT WILL OCCUR LATER THU AS H5 WAVE MOVES
OFFSHORE. WILL RAISE WINDS TO 30 KTS AND GUSTY AND RAISE SEAS A FEW
FEET TOWARD NOMOGRAM-LIKE VALUES FROM SURF CITY TO MURRELLS INLET.
WINDS/SEAS A TAD LOWER FROM MURRELLS INLET TO SOUTH SANTEE RIVER. PER
COORDINATION WITH MHX AND MPC...WILL DEFER RAISING GALE WARNING ONE
MORE SHIFT. WILL HOWEVER ADDRESS SHALLOW COASTAL FLOODING AND THE
EXPECTED ONSET OF GALES WITH AN MWS.
.ILM...SMALL CRAFT ADVISORY FROM SURF CITY NC TO SOUTH SANTEE RIVER SC.
MORGAN/PFAFF
FXUS62 KILM 290153 nc
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
805 PM MDT WED APR 28 1999
THE 02Z SURFACE ANALYSIS SHOWED TROUGH FROM CENTRAL MT THROUGH
CENTRAL CO. 00Z UPPER AIR ANALYSIS SHOWED DECENT THERMAL GRADIENT
AND THETA-E RIDGE THROUGH THIS AREA. FORCING AHEAD OF WEAK
SHORTWAVES ROTATING AROUND CA LOW HELPING SCT -SHRA/-TSRA TO DEVELOP
IN AFTERNOON HEATING. 00Z KUNR SOUNDING SHOWS US CAPPED. HEATING
GONE...BUT -SHRA SHOWING UP ON KUDX WSR-88D ACROSS SOUTHWEST WY. LOW
CLOUDS/MOISTURE HEADING UPSLOPE FROM CENTRAL SD PER OBSERVATIONS AND
IR LOOP. CONCERN TONIGHT IS PRECIPITATION AND FOG POTENTIAL.
THE 00Z RUC2 INITIALIZED JUST FINE. THE MAIN FORCING WILL REMAIN
WEST OF THE CWA WITH WEAKER FORCING ALONG FRONT SIDE OF THETA-E
RIDGE ACROSS NORTHEAST WY. THIS COMBINED WITH MILD UPPER SUPPORT
WILL GIVE NORTHEAST WY SCT -SHRA OVERNIGHT. MOISTURE MOVING UPSLOPE
WILL PROVIDE FOR AREAS OF FOG IN THE FOOTHILLS AFTER MIDNIGHT. GIVEN
CLOUDS AND DEW POINTS...TEMPERATURES LOOK PRETTY GOOD. MAY SPREAD
THE RANGE A LITTLE IN SOME SPOTS.
UPDATE ON TAP.
.KUNR...NONE.
HELGESON
FXUS63 KFSD 290203 COR sd
WEST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1005 PM CDT WED APR 28 1999
AIRMASS HAS BEEN WORKED OVER ON THE SOUTH PLAINS WITH LATEST LAPS
DATA SHOWING CAPE TO NEAR 2000 J/KG OVER THE LOW ROLLING PLAINS.
BEST STORMS OF THE EVENING HAVE BEEN OVER DICKENS AND FLOYD
COUNTIES. LOW LEVEL SHEAR/STORM RELATIVE HELICITY BETTER OVER THIS
REGION ALONG AND NORTH OF SURFACE BOUNDARY. LATEST SURFACE ANALYSIS
SHOWS FRONTAL BOUNDARY EXTENDING FROM THE METROPLEX WEST-NORTHWEST
TO KPVW. HEAVY RAIN POTENTIAL WILL CONTINUE TO THE NORTHEAST OF
KLBB AS 00Z UPPER AIR ANALYSIS SHOWS 25H FLOW BECOMING INCREASINGLY
DIFLUENT. 120 KNOT 25H JET ROUNDING BASE OF UPPER TROUGH WITH
LEFT EXIT REGION/ASSOCIATED UPPER DIVERGENCE MOVING INTO THE SOUTH
PLAINS OVERNIGHT. 00Z RUC/ETA MODELS SHOW LOW LEVEL MOISTURE AXIS
SHIFTING BACK TO THE WEST TONIGHT TO ALONG THE TEXAS/NEW MEXICO
BORDER. SOME INDICATIONS THAT THIS IS ALREADY HAPPENING WITH STRONG
CONVECTION OCCURRING OVER GAINES/ANDREWS COUNTIES ATTM. WITH
50H HEIGHT FALLS OCCURRING OVER THE GREAT BASIN AND SOUTHERN
ROCKIES...EXPECT MODELS ARE ON THE RIGHT TRACK SHOWING MOISTURE
SHIFTING BACK TO THE WEST. LATEST SURFACE ANALYSIS SHOWS DRYLINE
WEST OF KINK-KP07 LINE. WILL CONTINUE WITH HIGH POPS FOR SOUTH
PLAINS DOWN TO THE PERMIAN BASIN FOR REDEVELOPMENT OF CONVECTION
LATER TONIGHT.
.LBB...NONE.
TINSLEY
FXUS74 KFWD 290230 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
245 AM MDT THU APR 29 1999
MOST CONVECTION HAS QUIETED DOWN THIS MORNING THOUGH ONE VIGOROUS AREA
MOVING NORTHWEST AT 40 KNOTS OVER STILLWATER COUNTY. CUTOFF UPPER LOW
OVER SOUTHERN GREAT BASIN WILL MOVE LITTLE DURING PERIOD WITH MOIST FLOW
CONTINUING OVER FORECAST AREA. FILLING NATURE OF LOW ALLOWING SOME
WARMING ALOFT TO OCCUR OVER FORECAST AREA WITH MID LEVEL LAPSE RATES NOT
AS STEEP AS WEDNESDAY AFTERNOON...ESPECIALLY OVER EAST. SURFACE FRONT
VERY CLOSE TO BILLINGS AT THIS HOUR WITH SNOW FALLING AT KLWT AND KLVM.
EXPECT TODAYS BEST CHANCE OF STRONG THUNDERSTORMS ALONG KBIL-KGGW WITH
WARMING ALOFT REDUCING INSTABILITY OVER EASTERN ZONES. DIFFERENCES
BETWEEN ETA/AVN MODEL SOUNDINGS WITH AVN SHOWING BETTER SHEAR AND LAPSE
RATES. LOWER CONFINDENCE ON STORM TYPE/POTENTIAL TODAY AND WILL LEAVE
TO DAY SHIFT TO ANALYZE. DESPITE COOL TEMPS FOR WESTERN PORTIONS OF
CWFA...JET MAX AT BASE OF TROUGH THIS MORNING TRACKS ACROSS WESTERN
WYOMING THIS AFTERNOON ...WITH RESULTANT LEFT EXIT APPROACHING REGION.
THUS WILL KEEP MENTION OF THUNDERSTORMS IN ALL ZONES. 03Z RUC INDICATES
COLDER AIR WILL REACH BILLINGS LATER THIS MORNING...BUT EXPECT LACK OF
PRECIPITATION DURING THAT TIME PERIOD WILL PREVENT ANY SNOW FROM BEING
OBSERVED. WESTERN 6 COUNTIES SHOULD SEE SOME SNOW THIS MORNING AND WILL
MENTION LESS THAN AN INCH ACCUMULAITON. LITTLE CHANGE FOR TOMORROW AND
LOW CONFIDENCE.
FOR EXTENDED...WESTERLY FLOW DEVELOPS WITH TROUGHINESS OVER MONTANA.
LIKELY CONTINUED COOL AND POTENTIAL FOR WET. BORSUM
BIL WB 059/045 070/048 065 59663
LVM .. 051/039 063/... ... 59686
HDN .. 060/045 072/... ... 59663
MLS .. 070/050 075/045 ... 59333
4BQ .. 065/049 073/... ... 59333
BHK .. 065/049 072/... ... 59333
SHR WB 057/044 070/044 065 59664
BUR ** 046/032 047/034 048 59664
FXUS65 KTFX 290845 mt
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
245 AM CDT THU APR 29 1999
MODELS CONTINUE IN GOOD AGREEMENT WITH LARGE SCALE UPPER LEVEL
FEATURES. FA UNDER WESTERN EDGE OF EVOLVING OMEGA BLOCK WITH
SOUTHEASTERLY FLOW. DEEP MOISTURE AND SIGNIFICANT INSTABILITIES
REMAIN WEST OF ND/MT BORDER. PROBLEMS TODAY INCLUDE PERSISTENT LOW
CLOUDS SOUTHWESTERN CORNER AND TEMPERATURES. KHEI NEARLY 20 DEGREES
COOLER YTDY UNDER LOW CLOUDS. MODELS.IN POOR AGREEMENT ON LLVL
MOISTURE FIELDS WITH RUC AND ETA KEEPING LOW LVL MOISTURE IN PLACE
TODAY...NGM/AVN MOVE RH WEST DURING DAY AND RETURN IT AGAIN
TONIGHT. BELEIVE LOW CLOUDS WILL PERSIST AT LEAST UNTIL EARLY
AFTERNOON. WILL KEEP THAT ZONE WELL BELOW GUIDANCE...ELSEWHERE
YESTERDAYS COMPROMISE BETWEEN AVN/FWC GUIDANCE WORKED WELL AND WILL
CONTINUE AGAIN TODAY.
.BIS...NONE
HW
FXUS63 KFGF 290117 nd
WEST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
320 AM CDT THU APR 29 1999
BUSY MORNING...LATEST MODEL RUN AGAIN SIMILAR WITH UPPER PATTERN
THROUGH NEXT 48 HOURS AS DEEP 5H UPPER LOW CONTINUES TO BE CUT OFF
OVER SOUTHERN CA...WESTERN AZ WITH OMEGA BLOCK OVER CENTRAL U.S.
DIFFLUENT FLOW ALSO TO CONTINUE ACROSS FA NEXT 48 HOURS. WEAK
FRONTAL SYSTEM ALSO ACROSS THE SOUTH PLAINS AND FAVORED AREA OF
PRECIP TO BE ALONG AND NORTH OF THIS BOUNDARY THIS FORECAST CYCLE.
DRY LINE BACKED UP TO THE MOUNTAINS OF NEW MEXICO...SO PLENTY OF LOW
LEVEL MOISTURE TO ALSO BE IN PLACE ON THIS PACKAGE. DISTURBANCES TO
CONTINUE TO BE EJECTED AROUND THE LOW AND ACROSS WEST TEXAS NEXT 48
HOURS. HEAVY RAIN POTENTIAL WILL CONTINUE FOR ALL OF SOUTH PLAINS.
LATEST SURFACE ANALYSIS SHOWS FRONTAL BOUNDARY EXTENDING FROM JUST
SOUTH OF THE METROPLEX WEST-NORTHWEST TO NEAR PLAINVIEW. HEAVY RAIN
POTENTIAL WILL CONTINUE FROM LUBBOCK NORTHEAST AS 00Z UPPER AIR
ANALYSIS INDICATES 25H FLOW TO BECOME INCREASINGLY DIFLUENT. A 120+
KT 25H JET ROUNDING THE BASE OF THE UPPER TROUGH WITH LEFT EXIT
REGION AND ASSOCIATED UPPER DIVERGENCE TO MOVE ACROSS THE SOUTH
PLAINS EARLY THIS MORNING. 06Z RUC/ETA MODEL DATA SHOWS LOW LEVEL
MOISTURE AXIS SHIFTING WEST TO ALONG THE TX/NM BORDER...SO WILL KEEP
HIGH POPS THIS FORECAST CYCLE AS ALL INGRIDENTS IN PLACE FOR PRECIP
TO CONTINUE. WILL ALSO MENTION LOCALLY HEAVY RAIN FOR ALL OF SOUTH
PLAINS. WILL KEEP MENTION OF A FEW SEVERE STORMS POSSIBLE AS DRYLINE
HAS BACKED INTO NM. WILL BE SOME SLOSH EASTWARD TODAY...SO A FEW
STORMS TO BE SEVERE WITH HAIL PRIMARY THREAT. HOWEVER BELIEVE MAIN
THREAT THROUGH THIS FORECAST PERIOD TO BE HEAVY RAIN. HAVE DECIDED
TO GO WITH FLASH FLOOD WATCH SOUTH PLAINS DUE TO STORMS TRAINING
OVER AREA. NO CHANGES TO EXTENDED AT WET PATTERN TO CONTINUE.
LBB 069/053/069/052 687
.LBB...FLASH FLOOD WATCH TODAY TXZ 021>044.
XI
FXUS74 KLUB 290823 tx
DEEP SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
310 AM CDT WED APR 28 1999
NGM APPEARS TO BE ERRONEOUSLY GENERATING A STRONG VORT MAX EVOLVING
OUT OF CONVECTIVE COMPLEX THAT IS NOW WEAKENING RAPIDLY IN S CENTRAL
TX. AS RESULT IT PLACES 50 PCT POP IN FOR BRO/MFE FOR TODAY AS IT
BRINGS THIS PHANTOM DISTURBANCE RIGHT OVER VALLEY. ETA AND AVN AS
WELL AS RUC SWING A MUCH WEAKER VORT MAX NEWD WELL N OF HERE INTO
CENTRAL AND E TX THROUGH THE DAY WHICH APPEARS MORE REASONABLE. THOSE
AREAS SHOULD RECEIVE BRUNT OF TSTM POTENTIAL ON THIS THURSDAY IN
ADDITION TO POINTS FURTHER W IN W CENTRAL TX. CONVECTIVE OUTLOOK
CHARTS EVEN KEEP GENERAL TSTM POTENTIAL JUST TO W AND N OF DEEP S
TX FOR TODAY...THEN PLACE OUR AREA IN GENERAL AREA FRI AS FRONT
COMING DOWN FROM NNE PROVIDES A LITTLE MORE OF FOCUSING MECHANISM
FOR US. THIS SCENARIO FOLLOWS LAST FEW LOCAL FORECASTS AND WILL STAY
WITH THIS THINKING...NOT MENTIONING POPS TODAY BUT BRINGING IN SLIGHT
CHANCE FOR FRI THROUGH WEEKEND. LOW LEVEL WIND FLOW HERE IN 30-40 KT
RANGE CURRENTLY WHICH WILL ALSO ACT AGAINST ANY CONVECTIVE BUILDUPS.
WINDS ALOFT NOT FAVORABLE TO GUIDE TSTMS THAT MAY BUILD UP IN DRT
AREA AGAIN IN OUR DIRECTION...SWLY IN MID LEVELS ABOVE THE SLY LOWER
LEVEL FLOW. CLOUDS TODAY SHOULD FOLLOW PATTERN OF MOCLDY IN MORNING
GIVING WAY TO PC IN AFTERNOON THEN CLOUDING UP AGAIN BY EVENING. CLOUDS
TO BECOME MORE DOMINANT FRI INTO WEEKEND AS LOW LEVEL WINDS BACK TO E
ADDING MORE GULF MOISTURE. MAX TEMPS WILL RESPOND DOWNWARD FEW DEGREES.
FAN GUIDANCE SHOWS THIS COOLING MUCH MORE THAN FWC. WILL BLEND THE
TWO AND GO CLOSER TO FAN POPS. NOT MUCH HELP FROM APPROACHING FRONT
TO SEND MIN TEMPS A WHOLE LOT LOWER THAN THEY HAVE BEEN. GULF WINDS
SHOULD BE ON INCREASE AS HIGH PUSHES DOWN FROM NE AND MAY REACH SCA
CRITERIA LATE FRI AND SAT AS THAY BACK TOWARD E.
BRO BE 087/074 085/072 083 10/10/20/20
MFE BE 090/074 087/072 085 10/10/20/20
RGC BE 092/073 089/071 087 10/10/20/20
SPI BE 083/075 082/074 081 10/10/20/20
57-SYN/58-MESO
.BRO...NONE.
FXUS64 KMAF 290801 tx
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
1045 AM EDT THU APR 29 1999
EXAMINATION OF 12Z RAOBS FROM JAX/TBW (XMR WAS NOT AVBL) SHOWS
MOISTURE STILL SUFFICENT (1.3 - 1.5") AND MODERATE TO HIGH
INSTABILITY PARAMS - MODIFIED SBCAPE >2000 J/KG; LI'S TO -7; 500MB
TEMP -13C WITH MPRESSIVE 850-500MB LAPSE RATES.
COUPLE OF QUESTIONS FOR TODAY ARE WHETHER THE EAST COAST SEA BREEZE
WILL DEVELOP AND THE TIMING OF THE 500MB NEG VORTMAX (VORTMIN IF YOU
WILL) MOVING ACROSS THE AREA. LATEST RUC SHOWED ESSENTIALLY NEUTRAL
VV CONDS AFTER 18Z NORTH/21Z SOUTH. ADDTIONALLY...BACK DOOR FRONT
ACROSS NORTH FL WILL WEAKEN LOW LEVEL WESTERLIES...ESP THE FARTHER
NORTH ONE TRAVELS IN THE CWA.
FEELING IS THAT A SEA BREEZE WILL FORM MOST ALL AREAS TODAY AND
MAKE MORE INLAND PROGRESS DAB AREA. RESIDUAL SUBSIDENCE SOUTH MAY
DELAY THINGS NEAR LAKE OKEE. WILL UPDATE ZFP TO NUDGE POPS UP AND TO
TWEAK WINDS FOR EXPECTED SEA BREEZE DEVELOPMENT. STRONG STORMS WILL
BE MENTIONED IN THE ZFP AS WELL. THANKS FOR AT LENGTH COORD CALL
TPA.
MARINE...NO CHANGES TO WINDS/SEAS.
.MLB...NONE.
CRISTALDI
FXUS62 KJAX 291416 fl
AREA FORECAST DISCUSSION FOR EASTERN UPPER/NORTHERN LOWER MI
NATIONAL WEATHER SERVICE GAYLORD MI
1130 AM EDT THU APR 29 1999
HIGH AND DRY CONDITIONS PERSIST ACROSS THE REGION TODAY...WITH HIGH
TEMPS AGAIN BEING THE MAIN FORECAST CHALLENGE. WILL UPDATE ZONE
FORECASTS TO BUMP UP TEMPS A LITTLE IN MOST AREAS.
CURRENT (15Z) TEMPS ALREADY AROUND 60. 850 MB TEMPS WILL MODERATE A
COUPLE DEGREES THIS AFTERNOON (TO 4-5C)...WITH THE WARM ADVECTION
ACTUALLY TAKING PLACE FROM NORTH TO SOUTH IN THIS HIGHLY-AMPLIFIED
OMEGA BLOCK. AMPLIFIED UPPER LEVEL RIDGE/TROUGH PATTERN WITH
FORECAST AREA BETWEEN BOTH AXES WILL CONTINUE THE STRONG CONVERGENCE
ALOFT AND SUBSIDENCE AGAIN TODAY...THUS THE SUNNY SKIES.
OBSERVED KAPX 12Z SOUNDING AND RUC FORECAST SOUNDINGS SUGGEST MIXING
THROUGH 825 MB TODAY...ABOUT 25 OR SO MB HIGHER THAN YESTERDAY. IN
ADDITION...850-800 MB HEIGHTS TODAY ARE QUITE HIGH TO BEGIN WITH
(1610 M AT 850 MB AND 2100 M AT 800 MB). DRY-ADIABATIC MIXING
THROUGH 850 MB WOULD SUGGEST HIGHS IN THE MID 60S OVER LOWER
ELEVATIONS...LOWER 60S OVER THE HIGHER TERRAIN. HOWEVER...FACTORING
A LITTLE DEEPER MIXING AND ANOTHER DEGREE OR SO FOR A SUPERADIABATIC
LAPSE RATE NEAR THE SFC WOULD SUGGEST TEMPS NEAR 70 ACROSS SOME
AREAS. READINGS AGAIN WILL BE COOLER NEAR THE LAKE HURON SHORELINE
WITH THE NE WIND.
HURLEY
FXUS63 KMQT 291405 mi
NORTHEAST MONTANA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
919 AM MDT THU APR 29 1999
A QUASI-STATIONARY FRONT STRETCHED N-S ACROSS WRN VALLEY COUNTY THRU
JDN TO BETWEEN BIL AND MLS. TEMPS ONLY IN THE 30S WEST OF THE FRONT
AND 50S TO THE EAST.
WITH BLOCKING HIGH OVER GREAT LAKES AND CLOSED LOW IN SW US...FRONT
WILL MAKE LITTLE OR NO PROGESS EAST BEFORE RETREAT WEST THIS AFTERNOON.
12Z RUC GENERALLY IN AGREEMENT WITH 00Z ETA/AVN. WILL UPDATE FOR LOWER
TEMPS IN WRN ZONES WHERE FRONT WON'T BACK THRU UNTIL LATE AFTERNOON OR
EARLY EVENING. FORECAST IN ERN ZONES LOOKS GOOD.
GGW 432 068/048/073
GDV 322 067/047/071
FORRESTER
FXUS65 KBYZ 291513 mt
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
912 AM MDT THU APR 29 1999
SNOW ADVISORY FOR PARK AND SWEET GRASS WILL REMAIN IN EFFECT TODAY AS
WILL THE WINTER STORM WARNING ABOVE 4000 FEET FOR CARBON AND STILLWATER
COUNTIES.
AM PLANNING UPDATES ESPECIALLY FOR TEMPERATURE VARIATIONS.
PRECIPITATION ADVANCING NORTHWEST ACROSS AREA MAINLY FROM SHERIDAN
COUNTY THROUGH SOUTHWEST YELLOWSTONE ON ACROSS GOLDEN VALLEY COUNTY AND
WEST. LESS MOISTURE ACCORDING TO SATELLITE DEPICTION EAST. DRYING IS
WORKING ITS WAY NORTH INTO SOUTHERN WYOMING. FARTHER SOUTH OVER NEW
MEXICO...A VORT MAX IS MOVING NORTH RAPIDLY.
UPPER LEVEL LOW OVER NEVADA IS VIRTUALLY STACKED ACCORDING TO THE UPPER
AIR ANALYSIS. A SORT OF OMEGA BLOCK EAST WILL KEEP THIS FEATURE FROM
MOVING IN THE FORESEEABLE FUTURE. THUS...THE DREARY WEATHER WILL
CONTINUE. MOST PRECIPITATION LOOKS LIKE WILL OCCUR OVER THE WESTERN
PART OF THE COUNTY WARNING AREA WITH LESSER POSSIBILITIES EAST.
WITH THE DRYING MOVING NORTH...WILL HAVE TO WATCH THE EAST AND ALSO
SHERIDAN COUNTY. RUC MODEL INDICATES RATHER IMPRESSIVE CAPE THERE LATE
THIS AFTERNOON AND EARLY TONIGHT. CAPES NOT THAT IMPRESSIVE OVER
EASTERN MONTANA. BUT STILL BEARS WATCHING.
HAVE REGROUPED ZONES A BIT DUE TO TEMPERATURE VARIATIONS. EVEN
SO...TEMPERATURES WILL BE QUITE TRICKY. BREAKS IN THE CLOUDS WILL CAUSE
READINGS TO SHOOT UP RAPIDLY. WHERE TEMPS HAVE BEEN LOWERED...BELIEVE
CLOUD COVER WILL BE A MAJOR PLAYER. CHB
BIL WB 053/045 070/048 065 52963
LVM .. 040/032 063/... ... 52986
HDN .. 056/045 072/... ... 52963
MLS .. 070/050 075/045 ... 52333
4BQ .. 068/049 073/... ... 52333
BHK .. 065/049 072/... ... 52333
SHR WB 057/044 070/044 065 52664
FXUS65 KMSO 291438 mt
WESTERN NEVADA AND EASTERN CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
840 AM PDT THU APR 29 1999
UPPER LEVEL LOW STILL OVER SOUTHERN NEVADA THIS MORNING BRINGING WRAP
AROUND MOISTURE AND NORTHERLY WINDS INTO THE CWA. RADAR SHOWS AREA OF
INCREASING REFLECTIVITIES TO THE NE OF RENO OVER TO LOVELOCK AND DOWN
TO FALLON. NO SHOWERS REPORTED YET BUT LOWERING CLOUDS. CURRENT
FORECAST OF MOSTLY CLOUDY WITH SHOWERS APPEARS OK. LOOKING AT THE RUC
AND NGM FEEL THAT MENTION OF THUNDERSTORMS STILL GOOD. NGM STILL
INDICATING AREA OF INSTABILITY IN THE NW QUADRANT OF THE LOW...WITH
NEGATIVE LIS AND HIGH K VALUES BY 00Z THIS AFTERNOON. DID A COUPLE OF
MODEL SOUNDINGS ON AWIPS AT VARIOUS LOCATIONS IN ZONES 1 AND 4 WHICH
SHOWED INCREASING INSTABILITIES. MODEL SOUNDINGS DRIED OUT THE
BOUNDARY LAYER WHICH PROBABLY WONT HAPPEN TODAY SO WOULD EXPECT VALUES
OF LI AND K TO BE LOWER/HIGHER THAN MODELS INDICATE. TEMPERATURES
SHOULD CLIMB A FEW DEGREES OVER YESTERDAY WITH WARMING ALOFT...THOUGH
CLOUDS MAY CUT OFF SOME OF THE HEATING. BOTTOM LINE IS NO CHANGES TO
CURRENT FORECAST. CHALLENGE FOR THIS AFTERNOON WILL BE FIGURING OUT
THE POSSIBILITIES OF CONVECTION FOR TOMORROW. CAIRNS
.REV...EASTERN CALIFORNIA...NONE.
WESTERN NEVADA...NONE.
FXUS65 KREV 291111 nv
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
940 AM EDT THU APR 29 1999
12Z SFC ANALYSIS SHOWS A 1008/09MB LO PRES CNTR E OF CHS. AWIPS MSAS
ANALYSES SHOW THE LO NRLY STATIONARY THIS MRNG. THE 09Z RUC2 CONTS
THIS TREND WHILE THE 03Z MESO-ETA TRAKS THE LO EWD THIS AFTN.
MEANWHILE THE STG WEDGE CONTS IN PLACE TO OUR W. THE RUC BREAKS DN
THE WEDGE THIS AFTN WHILE THE MESO KEEPS IT IN TACT. FEEL THAT BOTH
FEATURES WILL STAY PAT 1ST PD KEEPING US IN THE LO CLDS. WV IMGRY
SHOWS THE UPR LO OVR THE TN VLY DRIFTING SWD. BOTH MDLS FCST THIS LO
TO OPEN UP DURING THE AFTN...SPREADING GOOD OMEGA OVR THE CWA. AREA
RADARS BEGINNING TO SHOW ADDL PRECIP W OF CAE/CLT WHICH SHUD MV THIS
WAY LTR. AWIPS LAMP PROGS CONT LIKELY POPS SO NO CHGS THERE.
ALTHO I/M NOT A BIG FAN OF LAMP TEMPS...THEY DO LOOK REASONABLE TDY
& WL MAKE SOME ADJUSTMENTS TO THE ZONES TO ACCT FOR THEM.
CWF...RUC/MESO BOTH HOLDING ONTO 30-35 KT WINDS OFF THE CST THIS
AFTN. WINDS AT/NEAR GALE FORCE ATTM ARND 20 NM & THEY SHOULD SUSTAIN
THERE THIS AFTN. NO BIG CHGS PLANNED.
.ILM...GALE WARNING FROM SURF CITY NC TO SOUTH SANTEE RIVER SC.
LGE
FXUS62 KMHX 290736 COR nc
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
900 PM EDT WED APR 28 1999
CURRENT SFC ANALYSIS INDICATES WEAKENING LOW OVR CENT TN WITH
FRONT/TROUGH SOUTHWARD. BACKDOOR FRONTAL BOUNDARY INTO N
GA STRETCHING SE INTO SE GA THEN EAST OFFSHORE. RADAR INDICATING AREAS
-RA OVER THE EASTERN HALF OF NC INTO NE SC...AND CONVECTIVE ACTIVITY
FROM KY/TN DOWN INTO GA WITH CONVERGING BOUNDARIES IN THE WARM SECTOR.
ETA MODEL APPEARS TO HAVE GOOD HANDLE ON SITUATION...AND CONFINES PCPN
TO THESE AFOREMENTIONED AREAS OF LOW LEVEL MOISTURE FLUX CONVERGENCE.
WILL LOWER POPS TON AND WORD AS PATCHY -RA/DZ FOR OUR CWA. SHOULDN'T SEE
SIGNIFICANT FOG WITH NEARLY STEADY TEMPS...SOME WIND...AND LITTLE PCPN
COVERAGE. ETA DOESNT SHOW ANY SIGNIFCANT ISEN LIFT OR UVV FOR US
OVERNIGHT. NOTHING MUCH GOING ON ALOFT...EXCEPT LATEST RUC II DOES
INDICATE VORT APPRCHG S CST LATE TON. THX CHS FOR COORD. WILL UPDATE SFP
AFTER GSP/CHS/ILM ZFPS.
.CAE...NONE.
MILLER
FXUS62 KCHS 290058 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
1000 AM EDT THU APR 29 1999
INVERTED AND STATIONARY SURFACE TROUGH OBSERVED THIS MORNING WITH LOW
PRESSURE CIRCULATION POSITIONED IN THE SOUTHERN CUMBERLAND PLATEAU.
THESE FEATURES HAVE SUPPORTED SOME LOCALLY HEAVY RAINFALL IN THIS
REGION. ON THE LARGER SCALE...TROUGH AMPLIFICATION IS EXPECTED EAST
OF THE MID-CONUS OMEGA BLOCK. EVENTUALLY...DRIER AIR IS PROGGED IN
ACROSS THE NORTHERN CWA THIS AFTERNOON. HOWEVER...CONSIDERING THE
29/12Z RUC PROGNOSIS FOR VORTICITY CENTERS NEARBY...WILL ONLY TRIM
BACK POPS IN THE NORTHERN CWA WITH MORE PATCHY PRECIPITATION COVERAGE
AND LIGHTER AMOUNTS. ALSO...WILL INCLUDE SOME WIND ADJUSTMENT.
TEMPERATURES LOOK O.K.
DM
FXUS64 KMRX 290816 tn