Flooding in Arkansas, March 24 to 31, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
659 PM CDT WED MAR 24 2010

.AVIATION...
VFR CONDS THIS EVENING WL SLOLY DETERIORATE LATER TNGT AS
SHRA/TSRA INCRS FM THE WEST. CIGS WL SLOLY LOWER TO MVFR CAT OVR
WRN AR LATER THIS EVENING AND DURG THE EARLY MRNG HRS ON THU FURTHER
EWD. ASSOCD CDFNT WL ENTER WRN AR TOWARD 25/06Z AND SHIFT EWD THRU
CNTRL AND ERN AR THU MRNG. MODELS INDC SOME DRIER AIR WL WORK
INTO CNTRL AND SRN AR THU AFTN...WITH PERSISTENT WRAPAROUND
MOISTURE/SCTD LGT RAIN OVR NRN AR. A FEW STORMS COULD REFORM OVR
CNTRL AND SRN AR THU AFTN...WITH VCTS MENTIONED. SLY WINDS AT 5
TO 10 KTS TNGT...WITH SHIFT TO THE W/SW AT 10 TO 20 KTS THU MRNG...
BCMG NWLY OVR NRN SECTIONS THU AFTN. /44/
&&

.PREV DISCUSSION... /ISSUED 304 PM CDT WED MAR 24 2010/

SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
A STRONG SYSTEM ALOFT WILL HEAD FROM THE SOUTHERN ROCKIES INTO THE
SOUTHERN PLAINS TONIGHT. A FEW SHOWERS WILL POP UP IN WESTERN
ARKANSAS BY THIS EVENING...WITH SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS DEVELOPING OVERNIGHT.

AS FAR AS SEVERE WEATHER...INSTABILITY WILL BE AN ISSUE TONIGHT.
GIVEN THE LOSS OF DAYTIME HEATING...AND WITH HIGHER DEWPOINTS
REMAINING ALONG THE GULF COAST...THERE WILL NOT BE ENOUGH FUEL FOR
ANY MORE THAN ISOLATED SEVERE STORMS.

THERE WILL BE LOCALLY HEAVY RAINFALL. AMOUNTS WILL AVERAGE ONE
QUARTER TO THREE QUARTERS OF AN INCH...WITH LOCALLY MORE THAN AN
INCH IN THE WEST.

THE SYSTEM WILL ARRIVE ON THURSDAY...WITH DRY AIR BUILDING INTO
SOUTHERN AND EASTERN SECTIONS OF THE STATE. RAIN WILL CONTINUE
FOR MUCH OF THE DAY ACROSS THE NORTH...WITH ANOTHER QUARTER TO
THREE QUARTERS OF AN INCH. A COLD FRONT WILL PUSH THROUGH THE
REGION BY AFTERNOON...WITH PRECIPITATION ENDING.

HIGH PRESSURE WILL FOLLOW WITH DRY CONDITIONS ON FRIDAY.
HOWEVER...ANOTHER FAST MOVING SYSTEM WILL APPROACH FROM THE WEST
TO BRING A CHANCE OF PRECIPITATION TO BEGIN THE WEEKEND.

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE IN THE
FORECAST IN WESTERN ARKANSAS ON SATURDAY...WITH SHOWERS/THUNDERSTORMS
LIKELY WEDNESDAY NIGHT. QPF DOES NOT APPEAR AS MUCH WITH THIS
SYSTEM AS WITH ITS PREDECESSOR. THERE WILL ALSO BE A LACK OF
INSTABILITY...WITH ANY SEVERE WEATHER REMAINING MINIMAL.

TEMPERATURES WILL DROP TO MORE NORMAL LEVELS IN THE NEAR TERM
AFTER WARM WEATHER RECENTLY.

LONG TERM...SUNDAY THROUGH WEDNESDAY
MODELS IN FAIRLY GOOD AGREEMENT AT THE START OF THE EXTENDED
TERM...WITH SOLUTIONS DIVERGING TOWARD THE END OF THE PERIOD.
EXTENDED TERM BEGINS WITH A FRONT PUSHING THROUGH THE STATE ON
SUNDAY...WITH AN ASSOCIATED UPPER LOW OVER THE MID MISSISSIPPI
VALLEY. SHOWERS AND THUNDERSTORMS WILL LIKELY OCCUR ALONG THE FRONT
ON SUNDAY AND I EXPECT PRECIPITATION WILL TAPER OFF SUNDAY NIGHT AS
THE FRONT PUSHES THROUGH AND THE UPPER LOW TRANSITIONS EASTWARD.

AIRMASS BEHIND THE FRONT WILL BRING DRIER AND JUST A BIT COOLER
TEMPS TO THE FORECAST AREA DURING THE EARLY PART OF THE WORK WEEK.

NWLY FLOW WILL DEVELOP ALOFT IN THE WAKE OF THE UPPER LEVEL
LOW...AND THEN THE MODELS START TO DIVERGE ON THEIR SOLUTIONS TOWARD
THE END OF THE PERIOD. GFS WANTS TO BRING A RETURN FLOW BACK THE
AREA FASTER THAN THE ECMWF. WILL GO WITH A BLEND BETWEEN THE ECMWF
AND GFS AT THE END OF THE FORECAST TERM AND WILL BRING TEMPS AND
DEWPOINTS GRADUALLY IN THE TUE-WED TIME FRAME. HOWEVER...TEMPS COULD
GET WARMER FASTER THAN ANTICIPATED IF THE RETURN FLOW SETS IN SOONER
THAN ANTICIPATED.
&&

.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1110 AM CDT WED MAR 24 2010

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-251000-
ARKANSAS-BAXTER-BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-CLEVELAND-
CONWAY-DALLAS-DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-HOT SPRING-
INDEPENDENCE-IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-LOGAN-LONOKE-
MARION-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-POPE-
PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-WHITE-
WOODRUFF-YELL-
1110 AM CDT WED MAR 24 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A LARGE PART OF ARKANSAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

A STORM SYSTEM IN THE SOUTHERN ROCKIES WILL HEAD INTO THE SOUTHERN
PLAINS TONIGHT. AHEAD OF THE SYSTEM...SHOWERS AND THUNDERSTORMS WILL
BECOME WIDESPREAD ACROSS ARKANSAS.

THERE COULD BE A FEW SHOWERS IN WESTERN SECTIONS OF THE STATE THIS
AFTERNOON...BUT THE BULK OF THE PRECIPITATION WILL DEVELOP DURING
THE OVERNIGHT HOURS. RAINFALL AMOUNTS WILL GENERALLY RANGE FROM A
QUARTER TO THREE QUARTERS OF AN INCH BY DAWN THURSDAY. LOCALLY OVER
AN INCH OF RAIN IS POSSIBLE IN THE WESTERN COUNTIES.

THERE COULD BE SOME SEVERE WEATHER IN PORTIONS OF SOUTHERN OKLAHOMA
AND NORTHERN TEXAS THROUGH THIS EVENING. BY THE TIME STORMS DEVELOP
IN ARKANSAS...THERE WILL BE A LOSS OF DAYTIME HEATING...AND HIGHER
MOISTURE LEVELS WILL BE TO THE SOUTH OF THE STATE. GIVEN THIS...
THERE WILL BE A LACK OF INSTABILITY...AND STORMS WILL HAVE
DIFFICULTY BECOMING SEVERE.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE STORM SYSTEM ARRIVE IN ARKANSAS ON THURSDAY...AND WILL DRAG A
COLD FRONT THROUGH THE STATE. DRIER AIR WILL SURGE INTO THE
REGION...WITH PRECIPITATION ENDING QUICKLY ACROSS SOUTHERN AND
EASTERN SECTIONS OF THE STATE. MOISTURE WILL WRAP AROUND THE
SYSTEM...AND RAIN IS EXPECTED TO CONTINUE FOR MUCH OF THE DAY IN THE
NORTHERN COUNTIES.

AS DRIER AIR ARRIVES...SOME HEATING WILL OCCUR IN AREAS ALONG THE
MISSISSIPPI RIVER. THE HEATING WILL TAKE PLACE JUST AHEAD OF THE
COLD FRONT...AND THIS COULD TRIGGER A SECOND ROUND OF STORMS EAST OF
LITTLE ROCK DURING THE AFTERNOON.

IT APPEARS MORE LIKELY THAT THESE NEW STORMS MAY NOT DEVELOP UNTIL
THE FRONT REACHES THE TENNESSEE VALLEY...WITH SEVERE WEATHER
POSSIBLE IN WESTERN TENNESSEE...MUCH OF MISSISSIPPI AND INTO
ALABAMA. IF STORM INITIATION TAKES PLACE EARLIER IN THE DAY...A FEW
SEVERE STORMS COULD AFFECT EASTERN ARKANSAS. THIS WILL BE MONITORED
CLOSELY.

ALL PRECIPITATION SHOULD END BY THURSDAY EVENING. DAYTIME RAINFALL
TOTALS COULD BE AS HIGH AS A HALF INCH TO AN INCH ACROSS THE NORTH.

HIGH PRESSURE WILL BRING DRY CONDITIONS ON FRIDAY...WITH A NEW FAST
MOVING STORM SYSTEM APPROACHING FROM THE WEST TO BEGIN THE WEEKEND.
THERE ARE CHANCES FOR SHOWERS AND THUNDERSTORMS SATURDAY AND
SATURDAY NIGHT. THE SYSTEM WILL EXIT TO THE EAST ON SUNDAY...AND
PRECIPITATION WILL TAPER OFF.

IT APPEARS THE SYSTEM WILL BE INTENSE INITIALLY...BUT WILL WEAKEN AS
IT NEARS THE STATE. THIS COMBINED WITH A LACK OF WARMTH AND MOISTURE
WILL KEEP CHANCES FOR SEVERE WEATHER MINIMAL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT...BUT MAY BE
NEEDED IN EASTERN ARKANSAS THURSDAY AFTERNOON.

&&

VISIT NWS LITTLE ROCK ON THE WEB. GO TO HTTP://WEATHER.GOV AND
CLICK ON CENTRAL ARKANSAS.

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