INTERIOR CENTRAL CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
835 PM PDT MON APR 26 1999
IR SATELLITE LOOP CONTINUING TO SHOW MID/HI CLOUDS ALONG FRONTAL
BOUNDARY ACROSS CNTRL CA. THE CLOUDS ARE THICKENING OVER THE
INTERIOR DUE TO ENHANCEMENT OVER THE MTNS. THE MOISTURE FLOW APPEARS
TO BREAK WEST OF THE COAST WHICH MAY ALLOW THE HIGH CLOUDS TO
DECREASE IN OPACITY LATER TONIGHT. 00Z RUC SHOWS A VORT LOBE
APPROACHING THE CNTRL COAST LATER TONIGHT WHILE KEEPING RH VALUES
UP. WILL MAKE SOME CHANGES TO THE CLOUD COVER FORECAST FOR TONIGHT
BUT AM HESITANT TO CHANGE MINIMUMS AS CLOUD COVER MAY THIN ENOUGH TO
ALLOW TEMPS TO FALL TO PROJECTED VALUES. SR
.HNX...NONE.
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
235 AM EDT TUE APR 27 1999
NGM/ETA IN EXCELLENT AGREEMENT WITH 500 MB PATTERN DURING NEXT 42
HOURS. BOTH MODELS BRING WEAKENING CLOSED LOW EASTWARD AND MERGE IT
WITH A NE-SW ORIENTED TROFF ALONG NE U.S. COAST. YET ANOTHER IN AN
ENDLESS SERIES OF DEEP TROFFS DEVELOPS OUT WEST AS A CORRESPONDING
RIDGE BUILD ACROSS MIDWEST. A WEAK SOUTHERN STREAM IS FORECAST
ALONG THE GULF COAST THROUGH THE PERIOD.
BESIDES ANNOYING FOG/CIG PROBLEMS HERE AT TLH...IMMEDIATE CONCERN
IS APPROACHING MCS NEAR NEW. 03 UTC RUC SHOWS THIS TO BE AN AREA OF
LOW-LEVEL MOISTURE FLUX CONVERGENCE AND A DEVELOPING THETA-E RIDGE
WELL AHEAD OF APPROACHING COLD FRONT. NGM/ETA INDICATE THAT AT
LEAST A PORTION OF THIS RAIN WILL REACH OUR CWA THIS AFTERNOON.
BOTH MODELS SHOW THE FRONT QUASI STALLING ACROSS CWA ON WED WITH
ANOTHER CHANCE FOR RAIN THEN. CURRENT ZONES AND CWF LOOK FINE.
FOURNIER
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STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1010 AM EDT TUE APR 27 1999
LITTLE OVERALL CHANGE. USEING RUC...SATELLITE AND RADAR AS GUIDE,
APPEARS WEAK SQUALL LINE LEFT OVER FROM LAST NIGHTS COMPLES MOVING
EAST, SHOULD ENTER GA AROUND 17-18Z AND MOVE EAST. WON'T BE SEVERE
BUT WILL BEAR WATCHING. PARTLY LCOUDY BECOMING MOATLY LCOUDY SOUTH
AND EAST LOOKS GOOD AS SKY CONDITION. TEMPS LOOK OK BUT WILL MONIOR.
.ATL....NONE.
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
940 AM EST TUE APR 27 1999
UPR LVL DIV TO EAST OF VERT STACKED LOW OVR NRN MO SUPPORTING BAND OF
SHOWERS FM NW-EC IND ATTM. UPR RDG AND DRIER AIR OVR NERN PORTION OF
CWA SHD CAUSE SHWR ACTVTY TO DIMINISH AS IT MOVES INTO NE/NC IND THIS
AFTN. WATER VAPOR LOOPS SUPPORT LATEST ETA/RUC WRT H5 TROF LIFTG NE
FM MO/ARK INTO SRN IND/KY BY EVE. WDSPD SHOWER ACTVTY EXPECTED TO
REACH INTO SRN PORTION OF CWA AHD OF THIS TROF BY EVE. SLGT MID LVL
INSTABILITY INDICATED BY MORNING AND FCST SOUNDINGS ALONG WITH >30K
FT ECHO TOPS MOVG INTO SWRN IND ATTM SUGGESTS MENTIONING CHC OF
THUNDER IN SRN ZONES. WL BE UPDATING IN/MI ZONES TO REFLECT PRECIP
TRENDS AND TO DROP MORNING MENTIONS.
.IWX...NONE.
JT
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
343 AM CDT MON APR 26 1999
LOW NOW OVR NCEN/NW MO MOVING VERY SLOWLY E. MDLS FAIRLY SIMILAR IN
THEIR SOLUTION WITH PUSHING THE LOW EAST. DRY AIR OVR ERN PTN OF THE
STATE WL PROLONG THE START OF PRECIP THERE BUT WE WILL BE IN GOOD
WRAP AROUND FLOW SO MOST EVERYONE SHOULD SEE AT LEAST SOME PRECIP.
THE RUC IS REALLY CLOSE WITH REALITY IN INITIALIZATION AND REASONABLE
THROUGH 18 HOURS. IT IS THE BEST OF THE 3 I THINK THEREFORE I WILL
TREND MORE TOWARDS THIS MDL. IF YOU BELIEVE THE RUC WE WILL SEE SOME
RAIN THIS MORNING FOLLOWED BY A CLOUDY AFTERNOON WITH AREAS OF
DRIZZLE OR SOME LIGHT RAIN. DRY PUNCH COMES IN THIS AFTERNOON AND
PRECIP WILL HAVE A HARD TIME FIGHTING THE DRY AIR...MUCH LIKE WHAT
ERN IA WL HAVE TO DEAL WITH TODAY. BOTTOM LINE IS WE WILL GET A GOOD
RAIN (ONE TO THREE QUARTERS OF AN INCH) THIS MORNING WITH LIGHTER
PRECIP THIS AFTN. WARM FRONT WITH THE LOW EXTENDS SE BUT IS EXPECTED
TO PUSH NORTH...PROBABLY INTO SE IA. RISK OF A LARGE OUTBREAK OF
THUNDER IS MINIMAL AS FRONT NEVER REALLY GETS HERE IN TIME.
TEMPS IN THE BALLPARK SO I WENT SLIGHTLY COOLER THAN PERSISTENCE DUE
TO THE RAIN AND CLOSE TO GUIDANCE.
.DSM...NONE
FAB
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
309 AM CDT TUE APR 27 1999
...GLOBALLY...
THE MID CONTINENT NORTH AMERICAN RIDGE CONTINUES TO BUILD WITH THE
TROFS OFF EACH COAST BECOMING MORE ESTABLISHED. THE TREND IN THE
LONGWAVE PATTERN POINTS TO THE DEVELOPMENT OF A BLOCKING RIDGE OVER
NORTH AMERICA WITH THE NORTHERN STREAM BEING THE DOMINANT STREAM.
THIS RESULTANT BLOCKING PATTERN MEANS VERY SLOW MOVEMENT OF SYSTEMS
ACROSS NORTH AMERICA FOR THE NEXT SEVERAL DAYS.
...LOCALLY...
WATER VAPOR AND PROFILER DATA HAVE STACKED SYSTEM MOVING INTO
WESTERN MISSOURI WITH PLENTY OF ENHANCED CLOUDS ACROSS IOWA. 06Z
SURFACE ANALYSIS HAS SURFACE LOW JUST NORTHEAST OF KMCI METRO AREA
WITH THE WARM FRONT ACROSS NORTHERN MISSOURI INTO CENTRAL ILLLINOIS.
MOISTURE ANALYSIS SHOWS A VERY SHARP GRADIENT FROM NORTH TO SOUTH
ACROSS THE FORECAST AREA WITH UPPER 20 DEW POINTS AROUND DBQ TO THE
50S AROUND EOK. KDVN 88D HAS A BAND OF RA RUNNING FROM THE TNU/MIW
AREA TO NORTH OF PIA. SURFACE OBS SWEEP INDICATE PRECIP REACHING THE
GROUND AT IOW AND MUT AND POINTS SOUTH. THIS PRECIP IS A RESULT OF
PLENTY OF QG FORCING IN THE 850-500 MB LEVEL.
PROBLEMS THIS PACKAGE ARE RAIN CHANCES AND CLOUDS/TEMPS.
MAJOR NCEP PROBLEMS WITH THE CRAYS HAVE MADE THIS A MORE CHALLENGING
FORECAST. WHAT PARTIAL GUIDANCE I HAVE INDICATES THE RUC IS DOING
BETTER THAN THE ETA/NGM IN THE NEAR TERM IN HANDLING THE OVERALL
FEATURES MORE CORRECTLY. ANOTHER FEATURE OF IMPORTANCE IS THE
STRATOSPHERIC INTRUSION INTO THE 425-450 MB AREA ON THE RUC WHICH
THROWS SEVERAL OTHER VARIABLES INTO THE EQUATION (YESTERDAY THIS
SAME INTRUSION APPEARS TO BE RESPONSIBLE FOR THE SEVERE WEATHER
DEVELOPMENT IN THE SOUTHERN PLAINS). THUS WILL GO CATEGORICAL
WORDING FOR THOSE AREAS THAT IT IS ALREADY RAINING WITH THUNDER
MENTIONED IN THE SOUTH AND GO WITH CHANCE POPS UP NORTH FOR TODAY.
WARM FRONTS USUALLY MANAGE TO EDGE INTO FAR SOUTHEAST IOWA WHEN
COMING UP FROM THE SOUTH AND THE RUC DOES SHOW THIS OCCURING DURING
THE DAY.
ETA TURNS OUT TO BE THE SLOWEST OF THE TWO MODELS AVAILABLE WHICH
WOULD BE CORRECT GIVEN THE DEVELOPMENT OF A BLOCKING PATTERN ALOFT.
EITHER WAY BOTH THE ETA AND NGM KEEP RAIN CHANCES GOING INTO TONIGHT
WITH A SHARP CUTOFF BY 12Z WEDNESDAY. THIS APPEARS TO BE IN RESPONSE
TO AN ABRUPT END TO THE QG FORCING IN THE 850-500 LEVELS AT 12Z
WEDNESDAY. THUS WILL KEEP RAIN CHANCES GOING TONIGHT AND GO DRY FOR
MOST OF THE AREA ON WEDNESDAY. FAR SOUTH MAY SEE SOME LINGERING
RA/DZ EARLY WEDNESDAY AND WILL WORD AS SUCH.
HPC RAINFALL FORECAST (REF 94Q/QPFPFD) GIVES MODERATE TO HEAVY
RAINFALL ACROSS THE AREA THROUGH 12Z WEDNESDAY WHICH WOULD NOT HELP
THE OVERALL HYDRO PROBLEMS. IF THIS COMES TO PASS AT LEAST THE
HEAVIEST RAINFALL WOULD BE ACROSS THE SOUTH WHERE THE GROUND/RIVERS
CAN AT LEAST HANDLE IT BETTER.
...EXTENDED...
WILL NOT TOUCH THE EXTENDED AS NO NEW GUIDANCE TO LOOK AT.
COORDINATED WITH DSM...LSE...CHI...SPI.
.DVN...NONE.
NC
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON
1000 AM EDT TUE APR 27 1999
CD FNT HAS MOVED S OF FA WITH HI PRES NOSING DOWN ACRS THE FA. STILL
PLENTY OF CI TO SW AHEAD OF SW MOVG INTO THE OHIO VALLEY. LOOKING AT
SATL AND RUC SHOWS MOST OF THIS CI STAYING ONLY OVR THE SRN PART FA
THRU THE DAY SO WL CHG NRN PART FA TO MSTLY SUNNY. WL MAKE ONLY
MINOR ADJUSTMENTS TO TEMPS AS CURRENT FCST MATCHES WELL WITH MRNG
SOUNDING.
.LWX...NONE.
JAB
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
328 PM EDT TUE APR 27 1999
MID AFTERNOON VISIBLE LOOP SHOW NICE DEFORMATION AXIS LYING NORTHWEST-
SOUTHEAST ACROSS LOWER MICHIGAN...WITH HIGH CLOUDS THINNING OUT AS THEY
RUN INTO NARROW HIGH AMPLITUDE UPPER RIDGE AXIS OVER THE REGION. NOT A
LOT OF CHANGE IN THE PATTERN WILL EXACERBATE DRY CONDITIONS ACROSS THE
AREA...AS WELL AS INCREASED FIRE DANGER ESPECIALLY AS TEMPERATURES WARM
UP TOWARD THE END OF THE WEEK.
MODELS CONTINUE TO ADVERTISE RATHER BLOCKY PATTERN THROUGH THE WEEKEND.
COMPACT SHORT WAVE OVER MO WILL UNDERCUT RIDGE AXIS...FORMING A
TEMPORARY REX BLOCK OVER THE AREA FOR WEDNESDAY...WHILE REDEVELOPMENT
OF A SOUTHWESTERN CUTOFF LOW WILL LEAD TO AN OMEGA BLOCK FOR LATTER
PORTIONS OF THE PERIOD AND INTO THE EXTENDED. RIDGING PARKED JUST TO
THE WEST OF THE GREAT LAKES WILL KEEP THINGS DRY ACROSS THE AREA
THROUGH THE SHORT TERM. NOT EXPECTING MUCH CI TO REACH INTO NORTHERN
LOWER TONIGHT AS DEFORMATION AXIS RE-ALIGNS ITSELF...WITH HIGH LEVEL
ISENTROPIC SURFACES ON THE ETA/RUC SHOWING CONTINUED DOWNSLOPING
MOTION. LOW LEVEL CAA IN EASTERLY FLOW WILL KEEP TEMPERATURES IN CHECK
DESPITE ABUNDANT APRIL SUNSHINE. WITH PROGGED 850MB TEMPERATURES A
DEGREE OR TWO COOLER WEDNESDAY WILL LEAN TOWARD PERSISTENCE FOR HIGHS
TOMORROW...MODIFIED DOWNWARD SLIGHTLY. A LITTLE WARMER FOR THURSDAY
WITH CONTINUED SUNNY SKIES.
.EXTENDED...NOT MUCH TO SAY HERE EXCEPT CONTINUED WARM AND DRY
CONDITIONS RIGHT ON INTO THE WEEKEND AS UPPER OMEGA BLOCK HOLDS FIRM
AND SURFACE HIGH PRESSURE REMAINS INTACT. LONGER RANGE MODELS SHOW
SOME DIFFERENCES IN EVENTUAL EVOLUTION OF SOUTHWESTERN U.S. CLOSED
LOW...BUT EFFECTS FROM THESE DIFFERENCES WON'T IMPACT THE GREAT LAKES
THROUGH THIS FORECAST PERIOD. TEMPERATURES SHOULD GRADUALLY WARM UP
WITH MID 60S-AROUND 70 DEGREE READINGS EXPECTED SATURDAY...AND LOWER-
MID 70S ACROSS NORTHERN MICHIGAN AWAY FROM THE LAKES BY SUNDAY.
.APX...NONE.
JPB
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FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
359 AM CDT TUE APR 27 1999
...UPDATE...
INVERTED TROF HAS DEEPENED OVER SRN RRV PAST FEW HOURS...AND IS
ENHANCING SHOWER ACTIVITY THIS AREA PER KABR 88D DATA. WHILE NONE OF THE
MODELS CAUGHT THIS FEATURE...NEW RUC AND ETA DID SHOW AREA OF WEAK
FRONTOGENETIC FORCING IN THIS GENERAL AREA. THIS FORCING TO DISSIPATE
DURING THE MORNING HOURS...THUS SHOWER ACTIVITY SHOULD END DURING THE
AM HOURS. HAVE ADJUSTED WRKFGF TO REFLECT CURRENT PCPN TRENDS FOR THIS
REASON.
NEW ZFPFGF TO BE SENT SHORTLY.
.FGF...NONE.
MEE/RJT
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1025 AM CDT TUE APR 27 1999
WILL MAKE ONLY MINOR CHANGES TO ZONES. TEMPS LOOK OKAY BUT WILL
TREND WINDS IN THE WEST TO LIGHT AND VARIABLE THIS AFTERNOON AS RUC
INDICATES SURFACE RIDGE TO MOVE INTO WESTERN ZONES. ONLY CLOUDS
WORTH NOTING ARE ACROSS NORTH CENTRAL AND WILL ADJUST WORDING
ACCORDINGLY. CU SHOULD START DEVELOPING BY NOON SO MOSTLY SUNNY
WORDING LOOKS GOOD ATTM.
FCSTID = 33 / DLF
.OUN...
OK...NONE.
TX...NONE.
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AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
545 PM MDT TUE APR 27 1999
LATEST LDS/WSR-88D LOOP INDICATES WEAK LINE OF -TSRA ENTERING
NORTHEAST WY/EXTREME SOUTHWEST SD/BLACK HILLS. 21Z RUC DEPICTS THIS
WELL WITH FORCING AHEAD OF WEAK SHORTWAVE SEEN ON WATER VAPOUR LOOP.
AFTER DISCUSSION WITH COWORKER...IT LOOKS LIKE MOST OF THE
PRECIPITATION WILL BE DIURNAL...SO DON/T EXPECT IT TO MAKE IT INTO
THE PLAINS.
FORECAST UPDATED.
.KUNR...NONE.
HELGESON
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AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
245 AM MDT TUE APR 27 1999
LATEST SFC ANALYS SHOWS LEE TROF FM ERN MT TO NE PANHANDLE...
EXTENDING INTO LOW OVR NW MO. A WEAK COLD FRONT ACROSS CENTRAL MT
REPRESENTS A DRYER AND SLIGHTLY COOLER AIR. PRESS FALL TRENDS AND
RUC SUPPORT THINKING THIS WILL NOT MOVE MUCH TODAY.
MODELS INITIATE WELL AND SHOW SOME FAIR AGREEMENT. MODELS PROG UPPER
JET TO MOVE ON BACK SIDE OF DEVLPNG UPR LVL TROF AS IT MOVES ONTO NW
U.S. SHORE BY 24HR. WHAT THE MODELS DONT SEE IS SRONGLY POS TILTED
TROF WELL OFF THE CA COAST VISIBLE IN WV IMAGES...WHICH WILL AFFECT
THE UPER TROF MOVING ON SHORE IN THIS FCST. BELIEVE NET EFFECT WILL
BE FOR UPPER LOW TO GET CUT OFF FURTHER SOUTH AND WEST THAN CURRENT
MODELS SUGGEST. ETA AND AVN HAVE BEEN TRENDING TO THIS SOLN EACH
SUCCESSIVE RUN. S/WV ENERGY WILL BE EJECTED FM THIS SYSTEM THROUGH
FCST PDS INTERACTING WITH RESIDUAL MOISTR...RESULT BEING CHC SHOWERS
OVR WRN PORTIONS OF CWA AND FURTHER WEST. WL LOOK FOR WK WAA TO SET
UP TONIGHT THRU WED AS 850MB AND SFC LOW ORGANIZE OVR SRN NV/CA. AN
ACCELERATION OF 850MB WINDS TONIGHT AND WED WILL BE ABLE TO MIX TO
SFC DURING DAY WED. LI VALUES OF -2 TO -4 OVR NE WY AND INTO WRN SD
AND MODEST CAPE WILL BRING MENTION OF TSTM THIS AFTN.
MOISTR WILL BE THE REAL QUESTION THIS FCST. MODELS PROG THIS CWA TO
BE ON EDGE OF MOISTR...AND PER ABOVE DISCUSSION I WILL TAKE THE MORE
OPTIMISTIC APPROACH THAT MOST MOISTR WILL REMAIN JUST WEST OF CWA.
JUST RECIEVED AVN NUMBERS AND ARE SIGNIFICANTLY WARMER THAN NGM OR
ME. HAVE GONE CLOSE TO NGM. AVN AND NGM POPS AGREE WELL.
.KUNR...NONE.
MUPRHY
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1235 PM CDT TUE APR 27 1999
LATEST KOHX SHOWING BULK OF SHOWERS/TSTMS WORKING ACROSS EASTERN
AREAS OF MIDDLE TENNESSEE AND ALONG PLATEAU. INDIVIDUAL CELLS HAVE
BEEN MOVING NORTHEAST AT 35KTS LAST COUPLE OF HOURS. WATER VAPOR
LOOP SHOWING BACK EDGE OF MID LEVEL MOISTURE ALONG TENNESSEE RIVER
WITH DRY PUNCH WORKING INTO WESTERN TENNESSEE. LATEST RUC IS SWINGING
A VORT LOBE OUT OF NORTHERN MISSOURI DOWN THROUGH WESTERN TENNESSEE
AT 18Z. RAINFALL HAS BEEN EAST OF THIS FEATURE LAST FEW HOURS.
17Z HAND ANALYZED SURFACE CHART HAS THE COLD FRONT NEAR THE
MISSISSIPPI RIVER IN EASTERN ARKANSAS.
VISIBLE SATELLITE IS SHOWING A NARROW BAND OF CUMULUS STARTING TO FORM
DOWN INTO NORTH CENTRAL ARKANSAS IN ASSOCIATION WITH COLD POOL ALOFT.
MODELS ARE SIMILAR IN SINKING COLD MISSOURI UPPER LOW DOWN INTO
MIDDLE TENNESSEE NEXT 48 HRS. WILL KEEP MENTION OF POPS GOING IN
FORECAST FOR ALL PERIODS THIS GO-AROUND.
PRELIMINARY NUMBERS:
NASHVILLE 58 73 53 70 4454
CROSSVILLE 54 68 50 63 6575
BOYD
01
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WYOMING STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
946 AM MDT TUE APR 27 1999
PREV FCST LOOKS TO BE IN FINE SHAPE AND ONLY MINOR CHGS WILL BE MADE AT
THE LT MRNG UPDATE. SHRTWV TROF NOW FROM SE ID TO W CNTRL UT AND HAS
SPRD SHWRS AS FAR E AS THE RKS AREA. EVN HAS BEEN SNOWING FOR AWHILE.
THE 00Z AND AVBL 12Z MDL RUNS INDICATE THAT THE FTR WILL HEAD NE AS
HGTS ALFT RISE. HWVR THE 12Z RUC INDICATES THAT THE FTR WILL HEAD MOR
E...INTO SE WY BY MID AFTN. FOR NOW WILL BUMP UP POPS ON THE W AND N
PRTS OF OUR CWA AND LEAVE WDLY SCT AFTN SHWRS AND TSTMS IN SE WY AND
MUCH OF THE WRN NEB PNHNDL. MAY BUMP UP TEMPS A BIT AS WELL FOR THE
AFTN AS SOME LCTNS ARE ALRDY IN THE MID 50S.
.CYS...NONE.
WEILAND
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EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
845 PM EDT TUE APR 27 1999
TONIGHT...WATER VAPOR LOOP AND RUC MODEL SHOWING A VORT LOBE VICINITY
SOUTHERN PENINSULA WHICH AIDED THE BOUNDARY INITIATED STORMS THIS
AFTERNOON AND EVENING. CONVECTION WHICH HAS BEEN DIMINISHING IN
AREAL COVERAGE SHOULD CONTINUE FOR ANOTHER HOUR OR TWO. WILL UPDATE
CURRENT PACKAGE TO REMOVE RAIN CHANCES ONCE THE CONVECTION FINALLY
DIES. ALSO PLAN TO ADD MENTION OF SOME PATCHY FOG/STRATUS IN AREAS
THAT HAD RAINFALL.
WEDNESDAY...DEEP MOISTURE DOES NOT LOOK QUITE HIGH ENOUGH FOR
ANYTHING MORE THAN SCATTERED COVERAGE OF AFTERNOON AND EVENING
STORMS. DEEP LAYER WEST TO SOUTHWEST FLOW WITH EMBEDDED DISTURBANCES
SHOULD RESULT IN THE BEST COVERAGE OVER EASTERN SIDE OF PENINSULA
AND WOULD NOT BE SURPRISED FOR A FEW SEVERE STORMS ONCE AGAIN.
MARINE...SURFACE RIDGE SOUTH OF THE AREA WITH 10 TO 15 KT SOUTH TO
SOUTHWEST GRADIENT. DO NOT SEE ANYTHING IN CURRENT FORECAST THAT
WOULD NEED UPDATING.
.MLB...NONE.
LASCODY
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
920 PM CDT MON APR 26 1999
LOOKS LIKE THINGS STARTING TO WIND DOWN. RADAR CONTINUES TO SHOW
SHOWERS MOVING WEST AND WEAKENING AS THEY MOVE INTO MORE SUBSIDENT
FLOW. OLD RUC HAD SOME ISENTROPIC LIFT OVER SE IA AT 00Z BUT THIS WAS
SHOWN TO WEAKEN BY 06Z AS UPPER AND SFC LOW OVER NE MO SLOWLY MOVES
EAST. A FEW SHOWERS MAY MAKE IT WEST OF I35 BUT MOST ACTIVITY SHOULD
REMAIN TO THE EAST OF THERE. MOST PCPN SHOULD BE OVER BY MORNING
ACROSS ALL BUT THE EXTREME SE. IN ZONES WILL KEEP OCCASIONAL SHOWERS
OR LIGHT RAIN CONTINUING WITH PCPN ENDING LATE TONIGHT ACROSS THE
NORTH AND WEST. MINS TONIGHT WILL BE IN THE LOW TO MID 40S NORTH AND
WEST AND UPPER 40S TO LOWER 50S SOUTHEAST.
.DSM...NONE
JAW
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
941 PM EDT TUE APR 27 1999
LINE OF STRONG TO MARGINALLY SEVERE CONVECTION LINED UP ACROSS
EASTERN PART OF CWA IN ASSOCIATION WITH MID-LEVEL VORT MAX AND HIGH
SFC BASED INSTABILITY. WILL BE OUT OF CWA IN NEXT HOUR OR TWO. 18Z
ETA AND 21Z RUC SHOW MID AND UPPER SUPPORT MOVING NORTHEAST OF AREA
WITH ONLY WEAK PATCHES OF LIFT AFTER MIDNIGHT. SFC BOUNDARY APPEARS
TO BE STRETCHED FROM JUST SOUTH OF GSO TO ILM. LITTLE MOVEMENT OVER
PAST COUPLE HOURS AND CURRENT SFC ANALYSIS DOES NOT SHOW A STRONG
PUSH BEHIND IT. SFC DWPTS STILL VERY HIGH ACROSS MOST OF CWA WITH
UPPER 60S TO NEAR 70 JUST TO OUR SOUTHWEST. BOUNDARY MAY SLIDE A
LITTLE SOUTHWEST OVERNIGHT AND ALLOW COOLER...DRIER AIR TO FILTER
INTO NORTHEAST SECTIONS OF CWA...BUT PLAN TO RAISE LOW TEMPS SOUTH
OF BOUNDARY. WILL CARRY LIKELY POPS UNTIL MIDNIGHT FOR EXTREME EAST.
WEAK IMPULSES...HIGH MOIST CONTENT AND BOUNDARY IN CWA IS REASON TO
KEEP POPS IN FORECAST OVERNIGHT. ALTHOUGH WILL LOWER TO CHC.
.GSP...NONE
MOYER
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AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
845 PM MDT TUE APR 27 1999
02Z SURFACE ANALYSIS SHOWED WEAK TROUGH ACROSS MT TO NE/S PANHANDLE.
WEAK SURFACE MOISTURE CONVERGENCE IS NOTED ALONG WITH 100-300J/KG
AVAILABLE PER ADAS. 00Z UPPER AIR ANALYSIS SHOWED 850-700MB THETA-E
AXIS ALONG WY/SD NE/CO BORDER. WATER VAPOUR LOOP INDICATED WEAK
SHORTWAVE NEAR THE AXIS WITH A BROKEN LINE OF -TSRA FROM NORTHEAST
WY TO EXTREME SOUTHWEST SD PER KUDX WSR-88D. CONCERN TONIGHT IS
EXTENT OF PRECIPITATION AND WIND DIRECTION.
THE 00Z RUC2 INITIALIZED ALRIGHT AND NEAR 03Z IT REPRESENTED
REALITY. WEAK DISTURBANCES WILL CONTINUE TO SUPPORT WEAK
PRECIPITATION ALONG THETA-E AXIS THROUGH 09Z. RUC2 QPF
SUPPORTS...BUT AS THE LEFT EXIT REGION OF A 70KT UPPER LEVEL JET
PASSES...ACTIVITY SHOULD DECREASE. HENCE...WILL KEEP SCATTERED POPS
SOUTHWEST OF A LINE FROM THE CENTRAL HILLS TO KIEN OR SO.
WIND DIRECTION WILL BE TWEAKED PER DISCUSSION WITH COWORKER. LOOKS
LIKE THINGS WILL BE MORE NORTHEASTERLY MOST AREAS EXCEPT VARIABLE IN
THE HILLS/FOOTHILLS.
UPDATE ON TAP.
.KUNR...NONE.
HELGESON
NNNN sd
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
910 PM CDT TUE APR 27 1999
SHWRS HAVE ENDED BUT PSBLTY OF A FEW MAKNG IT INTO SERN PART OF AREA
LATE TNGT...HINTED AT BY 00Z RUC...SEEMS ENUF TO LEAVE A LTL 20 PCT
POP ALONE. FCST THEREFORE LOOKS GOOD FOR NOW INCLUDG TEMPS WHICH
SHUD ONLY COOL VRY SLWLY. NO UPDATES FOR NOW.
.FSD...NONE
WILLIAMS
NNNN sd
WEST TEXAS FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE LUBBOCK TX
930 PM CDT TUE APR 27 1999
NO MAJOR CHANGES EXPECTED FOR THE FIRST PERIOD OTHER THAN MINOR
TWEEKING OF TEMPERATURES UP A CATEGORY FOR NORTHERN SECTIONS.
WAS ALL SET TO BUMP PRECIP CHANCES UP FOR WEDNESDAY AFTERNOON
INTO THE EVENING AFTER LOOKING AT 12Z MODEL RUNS...ESPECIALLY THE
ETA. AFTER LOOKING AT 00Z SOUNDINGS ACROSS SOUTH TEXAS...APPEARS
THE ETA IS OVERLY ZEALOUS BRINGING MOISTURE BACK INTO THE REGION
WEDNESDAY. 00Z CRP/BRO SOUNDINGS SHOWED MOIST LAYER ONLY UP TO
975/950 MB RESPECTIVELY. 00Z RUC SHOWS 85H MOIST AXIS MOVING NORTHWEST
ALONG THE RIO GRANDE INTO SOUTHERN PORTIONS OF THE FORECAST AREA BY
12Z WEDNESDAY. ALL SHORT RANGE MODELS SHOWED A SHORT WAVE TROUGH
MOVING OUT OF THE SOUTHERN ROCKIES INTO WEST TEXAS WEDNESDAY
AFTERNOON. IF WE CAN GET THE MOISTURE BACK INTO THE AREA...WIND
PROFILES ARE SUCH THAT ROTATING STORMS WOULD BE POSSIBLE. THIS
WOULD BE MORE LIKELY TO OCCUR AFTER 00Z AS LOW LEVEL FLOW BACKS
IN RESPONSE TO UPPER HEIGHT FALLS TO THE WEST THUS INCREASING THE
LOW LEVEL SHEAR AND STORM RELATIVE HELICITY OVER THE REGION. MODELS
STRONGLY SUGGEST UPPER LEVEL FLOW OVER THE REGION WILL BE VERY
DIFLUENT WITH DIVERGENCE ASSOCIATED WITH LEFT EXIT REGION OF 100
KNOT 30H JET MOVING ACROSS THE SOUTH PLAINS WEDNESDAY NIGHT. FEEL
THE NEED TO INCREASE POPS TO AT LEAST CHANCE CATEGORY FOR THE SOUTH
PLAINS AND LOW ROLLING PLAINS FOR WEDNESDAY NIGHT. IF THE ETA IS
RIGHT WITH THE UPPER LEVEL WIND FIELDS AND POSITION OF THE LOW LEVEL
THETA-E RIDGE AXIS...COULD SEE BACK BUILDING STORMS AND HEAVY RAINFALL
POTENTIAL ACROSS THIS AREA WEDNESDAY NIGHT.
THE HEAVY RAIN POTENTIAL WILL LINGER INTO SATURDAY AS UPPER LOW
STAGNATES OVER THE SOUTHWEST UNITED STATES IN RESPONSE TO OMEGA
BLOCK PATTERN OVER SOUTHERN CANADA AND NORTH CENTRAL UNITED STATES.
PATTERN MAY FINALLY BE SETTING UP TO RECEIVE BENEFICIAL RAINFALL
ACROSS THE WEST TEXAS AREA THROUGH THE LATTER HALF OF THE WEEK.
.LBB...NONE.
TINSLEY
NNNN tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
825 PM CDT TUE APR 27 1999
ONLY MINOR ADJUSTMENTS TO THE ONGOING FORECAST ARE RECOMMENDED.
SURFACE ANALYSES INDICATE A CHAOTIC WIND PATTERN RIGHT NOW...BUT
WINDS SHOULD GRADUALLY COME AROUND TO THE SOUTHEAST PER THE LATEST
RUC MODEL GUIDANCE. FOR TX...WE RECOMMEND ADJUSTING THE WINDS TO
REFLECT THIS THINKING. WE'VE ALSO MADE SOME MINOR TWEAKS HERE AND
THERE FOR TEMPERATURES TONIGHT. NM ZONES LOOK FINE AT THIS END
AND WE RECOMMEND NO CHANGES THERE. WZIS SHORTLY...70.
NNNN tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
855 PM EDT TUE APR 27 1999
MAIN FCST QUESTS OVERNIGHT WITH COVERAGE OF SHRA AND HOW FAR NE TO
CARRY HIGHER POPS LATER ON. SFC ANALYS SHOWS LARGE DEWPT DIFFS CONTG
OVER THE REGION WITH WEDGE OF DRIER AIR TRYING TO HOLD EAST OF THE
MTNS AND BULGE OF MORE INSTAB ALONG THE WRN SLOPES SWD INTO NC. RADAR
INDICATES SHRA A BIT MORE WDSPRD THAN EARLIER BUT INTENSITY ON
THE DECRS WITH BEST JUICE TO THE SOUTH AND DRY AIR OUT EAST. LATEST
MESO-ETA/RUC AND MM5 SUGGEST RA TO INCREASE AGAIN ESPCLY ALONG AND
WEST OF THE BLUE RDG LATER WITH DVLPG STRONGER EASTERLY UPSLOPE AND
OVERRUNNING PER WEAK VORT/FRONT SOUTH. THUS PLAN TO CONT BEST POPS
ACROSS THE MTNS ALTHOUGH EXPECT GIVEN DMNSHG ECHOES OFF MRX 88D AND
DEEP CONVECTION WELL SOUTH INTO NC THAT FAR WRN ZONES MAY CUTOFF TO
ONLY SCT SHRA AFTR MIDNGT. ALSO THINK POPS ERN/NE ZONES A BIT HIGH
GIVEN SLOW TO EXIT SFC RIDGING AND DRY AIR SO WILL BACK OFF A CAT OR
SO THERE. FCST TEMPS APR A BIT LOW IN SPOTS MOST ZONES WITH COOL
POOL LKLY NOT TO DEEPEN UNTIL EARLY WED. WILL BUMP LOWS CLOSER TO
PROGGED LAMP NUMBERS SIMILAR TO EARLIER FAN OTRW OK.
.RNK...
VA...NONE.
NC...NONE.
WV...NONE.
JH
NNNN va
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 fl
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 mi
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
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
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
845 PM EDT TUE APR 27 1999
TONIGHT...WATER VAPOR LOOP AND RUC MODEL SHOWING A VORT LOBE VICINITY
SOUTHERN PENINSULA WHICH AIDED THE BOUNDARY INITIATED STORMS THIS
AFTERNOON AND EVENING. CONVECTION WHICH HAS BEEN DIMINISHING IN
AREAL COVERAGE SHOULD CONTINUE FOR ANOTHER HOUR OR TWO. WILL UPDATE
CURRENT PACKAGE TO REMOVE RAIN CHANCES ONCE THE CONVECTION FINALLY
DIES. ALSO PLAN TO ADD MENTION OF SOME PATCHY FOG/STRATUS IN AREAS
THAT HAD RAINFALL.
WEDNESDAY...DEEP MOISTURE DOES NOT LOOK QUITE HIGH ENOUGH FOR
ANYTHING MORE THAN SCATTERED COVERAGE OF AFTERNOON AND EVENING
STORMS. DEEP LAYER WEST TO SOUTHWEST FLOW WITH EMBEDDED DISTURBANCES
SHOULD RESULT IN THE BEST COVERAGE OVER EASTERN SIDE OF PENINSULA
AND WOULD NOT BE SURPRISED FOR A FEW SEVERE STORMS ONCE AGAIN.
MARINE...SURFACE RIDGE SOUTH OF THE AREA WITH 10 TO 15 KT SOUTH TO
SOUTHWEST GRADIENT. DO NOT SEE ANYTHING IN CURRENT FORECAST THAT
WOULD NEED UPDATING.
.MLB...NONE.
LASCODY
NNNN
FXUS62 KTBW 280046
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
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
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
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
920 PM CDT MON APR 26 1999
LOOKS LIKE THINGS STARTING TO WIND DOWN. RADAR CONTINUES TO SHOW
SHOWERS MOVING WEST AND WEAKENING AS THEY MOVE INTO MORE SUBSIDENT
FLOW. OLD RUC HAD SOME ISENTROPIC LIFT OVER SE IA AT 00Z BUT THIS WAS
SHOWN TO WEAKEN BY 06Z AS UPPER AND SFC LOW OVER NE MO SLOWLY MOVES
EAST. A FEW SHOWERS MAY MAKE IT WEST OF I35 BUT MOST ACTIVITY SHOULD
REMAIN TO THE EAST OF THERE. MOST PCPN SHOULD BE OVER BY MORNING
ACROSS ALL BUT THE EXTREME SE. IN ZONES WILL KEEP OCCASIONAL SHOWERS
OR LIGHT RAIN CONTINUING WITH PCPN ENDING LATE TONIGHT ACROSS THE
NORTH AND WEST. MINS TONIGHT WILL BE IN THE LOW TO MID 40S NORTH AND
WEST AND UPPER 40S TO LOWER 50S SOUTHEAST.
.DSM...NONE
JAW
NNNN
This data is from the
FXUS74 KFWD 281528
WEST TEXAS FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE LUBBOCK TX
930 PM CDT TUE APR 27 1999
NO MAJOR CHANGES EXPECTED FOR THE FIRST PERIOD OTHER THAN MINOR
TWEEKING OF TEMPERATURES UP A CATEGORY FOR NORTHERN SECTIONS.
WAS ALL SET TO BUMP PRECIP CHANCES UP FOR WEDNESDAY AFTERNOON
INTO THE EVENING AFTER LOOKING AT 12Z MODEL RUNS...ESPECIALLY THE
ETA. AFTER LOOKING AT 00Z SOUNDINGS ACROSS SOUTH TEXAS...APPEARS
THE ETA IS OVERLY ZEALOUS BRINGING MOISTURE BACK INTO THE REGION
WEDNESDAY. 00Z CRP/BRO SOUNDINGS SHOWED MOIST LAYER ONLY UP TO
975/950 MB RESPECTIVELY. 00Z RUC SHOWS 85H MOIST AXIS MOVING NORTHWEST
ALONG THE RIO GRANDE INTO SOUTHERN PORTIONS OF THE FORECAST AREA BY
12Z WEDNESDAY. ALL SHORT RANGE MODELS SHOWED A SHORT WAVE TROUGH
MOVING OUT OF THE SOUTHERN ROCKIES INTO WEST TEXAS WEDNESDAY
AFTERNOON. IF WE CAN GET THE MOISTURE BACK INTO THE AREA...WIND
PROFILES ARE SUCH THAT ROTATING STORMS WOULD BE POSSIBLE. THIS
WOULD BE MORE LIKELY TO OCCUR AFTER 00Z AS LOW LEVEL FLOW BACKS
IN RESPONSE TO UPPER HEIGHT FALLS TO THE WEST THUS INCREASING THE
LOW LEVEL SHEAR AND STORM RELATIVE HELICITY OVER THE REGION. MODELS
STRONGLY SUGGEST UPPER LEVEL FLOW OVER THE REGION WILL BE VERY
DIFLUENT WITH DIVERGENCE ASSOCIATED WITH LEFT EXIT REGION OF 100
KNOT 30H JET MOVING ACROSS THE SOUTH PLAINS WEDNESDAY NIGHT. FEEL
THE NEED TO INCREASE POPS TO AT LEAST CHANCE CATEGORY FOR THE SOUTH
PLAINS AND LOW ROLLING PLAINS FOR WEDNESDAY NIGHT. IF THE ETA IS
RIGHT WITH THE UPPER LEVEL WIND FIELDS AND POSITION OF THE LOW LEVEL
THETA-E RIDGE AXIS...COULD SEE BACK BUILDING STORMS AND HEAVY RAINFALL
POTENTIAL ACROSS THIS AREA WEDNESDAY NIGHT.
THE HEAVY RAIN POTENTIAL WILL LINGER INTO SATURDAY AS UPPER LOW
STAGNATES OVER THE SOUTHWEST UNITED STATES IN RESPONSE TO OMEGA
BLOCK PATTERN OVER SOUTHERN CANADA AND NORTH CENTRAL UNITED STATES.
PATTERN MAY FINALLY BE SETTING UP TO RECEIVE BENEFICIAL RAINFALL
ACROSS THE WEST TEXAS AREA THROUGH THE LATTER HALF OF THE WEEK.
.LBB...NONE.
TINSLEY
NNNN
FXUS64 KMAF 280214 AMD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
825 PM CDT TUE APR 27 1999
ONLY MINOR ADJUSTMENTS TO THE ONGOING FORECAST ARE RECOMMENDED.
SURFACE ANALYSES INDICATE A CHAOTIC WIND PATTERN RIGHT NOW...BUT
WINDS SHOULD GRADUALLY COME AROUND TO THE SOUTHEAST PER THE LATEST
RUC MODEL GUIDANCE. FOR TX...WE RECOMMEND ADJUSTING THE WINDS TO
REFLECT THIS THINKING. WE'VE ALSO MADE SOME MINOR TWEAKS HERE AND
THERE FOR TEMPERATURES TONIGHT. NM ZONES LOOK FINE AT THIS END
AND WE RECOMMEND NO CHANGES THERE. WZIS SHORTLY...70.
NNNN
FXUS74 KFWD 280126 AMD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
855 PM EDT TUE APR 27 1999
MAIN FCST QUESTS OVERNIGHT WITH COVERAGE OF SHRA AND HOW FAR NE TO
CARRY HIGHER POPS LATER ON. SFC ANALYS SHOWS LARGE DEWPT DIFFS CONTG
OVER THE REGION WITH WEDGE OF DRIER AIR TRYING TO HOLD EAST OF THE
MTNS AND BULGE OF MORE INSTAB ALONG THE WRN SLOPES SWD INTO NC. RADAR
INDICATES SHRA A BIT MORE WDSPRD THAN EARLIER BUT INTENSITY ON
THE DECRS WITH BEST JUICE TO THE SOUTH AND DRY AIR OUT EAST. LATEST
MESO-ETA/RUC AND MM5 SUGGEST RA TO INCREASE AGAIN ESPCLY ALONG AND
WEST OF THE BLUE RDG LATER WITH DVLPG STRONGER EASTERLY UPSLOPE AND
OVERRUNNING PER WEAK VORT/FRONT SOUTH. THUS PLAN TO CONT BEST POPS
ACROSS THE MTNS ALTHOUGH EXPECT GIVEN DMNSHG ECHOES OFF MRX 88D AND
DEEP CONVECTION WELL SOUTH INTO NC THAT FAR WRN ZONES MAY CUTOFF TO
ONLY SCT SHRA AFTR MIDNGT. ALSO THINK POPS ERN/NE ZONES A BIT HIGH
GIVEN SLOW TO EXIT SFC RIDGING AND DRY AIR SO WILL BACK OFF A CAT OR
SO THERE. FCST TEMPS APR A BIT LOW IN SPOTS MOST ZONES WITH COOL
POOL LKLY NOT TO DEEPEN UNTIL EARLY WED. WILL BUMP LOWS CLOSER TO
PROGGED LAMP NUMBERS SIMILAR TO EARLIER FAN OTRW OK.
.RNK...
VA...NONE.
NC...NONE.
WV...NONE.
JH
NNNN
FXUS71 KRLX 280054
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