Severe Thunderstorm Warning 13, NWS Little Rock, AR

AREA FORECAST DISCUSSION...UPDATE FOR AVIATION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
540 PM CST THU FEB 26 2009

.AVIATION...
OVERALL VFR CEILINGS TO START THE PERIOD. A COLD FRONT WILL
GRADUALLY MOVE INTO AR OVER THE NEXT 12 HRS...BRING OVERALL MVFR
CEILINGS WITH ISOLATED IFR CEILINGS WITH SHOWERS AND THUNDERSTORMS.
THE STORMS WILL REACH NW AR AREAS AROUND 01Z TO 03Z...CENTRAL AREAS
AROUND 04Z TO 08Z...THEN SOUTHERN AREAS 08Z TO 13Z. ISOLATED STRONG
TO SEVERE STORMS WILL BE POSSIBLE. ELEVATED SURFACE SOUTHWEST WINDS
10 TO 20 MPH AND GUSTY AHEAD OF THE COLD FRONT...THEN NORTHWEST TO
NORTH WINDS 10 TO 15 MPH BEHIND THE FRONT. WIND SHEAR EXPECTED ALONG
THE FRONT. (59)

&&
.PREV DISCUSSION... /ISSUED 250 PM CST THU FEB 26 2009/

.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
SURFACE ANALYSIS INDICATES COLD FRONT OVER CENTRAL OKLAHOMA.
GRADIENT BETWEEN THE FRONT AND HIGH PRESSURE OVER THE SOUTHEAST
CONUS HAS ALLOWED FOR GUSTY WINDS OVER THE ENTIRE AREA...WITH SOME
GUSTS APPROACHING 40 MPH. WARMUP HAS BEEN WELL INTO THE 70S IN
ARKANSAS OUT AHEAD OF THE FRONT. THE ONLY THING SAVING US FROM
HIGHER TEMPS HAS BEEN THE THICK CLOUD COVER.

ANALYSIS OF MORNING UPPER AIR DATA REVEALS A VERY STRONG CAPPING
INVERSION. THIS HAS KEPT CONVECTION FROM GETTING STARTED OUT AHEAD
OF THE FRONT...EVEN WITH CLEARING AREAS AND TEMPERATURES NEAR 90
DEGREES IN SOUTHERN OKLAHOMA.

GRADUAL DESTABILIZATION EXPECTED TO OCCUR THIS EVENING AS UPPER
LEVEL IMPULSES MOVE THROUGH IN THE UPPER FLOW AND INTERACT WITH
THE FRONT...AND LOW LEVEL JET DYNAMICS KICK IN. SHOWERS/STORMS
WILL DEVELOP ALONG THE FRONT...AS IT MOVES INTO THE MID SOUTH
REGION. MODELS SHOWING THE FRONT MOVING INTO THE FORECAST AREA
SOME TIME BETWEEN 03 AND 06Z.

SEVERE STORMS COULD OCCUR...WITH HAIL AND WIND BEING THE PRIMARY
THREATS. FRONT WILL HANG UP NEAR SOUTHERN ARKANSAS BY FRIDAY
MORNING...A CONSEQUENCE OF NEARLY PARALLEL UPPER FLOW. SEVERAL WAVES
WILL MOVE ALONG THE FRONT...INTERACTING WITH IT AND CONTINUING THE
CHANCE OF SHOWERS AND THUNDERSTORMS. SEVERE STORMS A POSSIBILITY ON
FRIDAY. THIS WOULD LIKELY BE ALONG AND NORTH OF THE FRONT
/ELEVATED HAILERS/. WITH THIS SETUP...LOCALLY HEAVY RAIN IS NOT
OUT OF THE QUESTION...WITH SOME ONE TO TWO INCH AMOUNTS POSSIBLE.

LOW PRESSURE DEVELOPING ALONG THE FRONT...ALONG WITH A DEEPENING
UPPER LOW MOVING DOWN FROM THE NORTHERN PLAINS WILL PUSH THE FRONT
OUT OF THE AREA FRIDAY NIGHT AND SATURDAY. HOWEVER...MOISTURE
ASSOCIATED WITH THE UPPER LOW WILL REMAIN OVER THE AREA...AND
DEEPENING COLD AIR COLUMN WILL ALLOW FOR A RAIN/SNOW MIX ACROSS
THE NORTH DURING THIS PERIOD. ANY SNOW WILL BE LIGHT AND LITTLE
IF ANY ACCUMULATIONS ARE EXPECTED.

UPPER LOW WILL DIVE SOUTHEAST AND OUT OF THE AREA LATE SATURDAY
INTO SUNDAY...WITH COLDER AIR FOLLOWING THE SYSTEM. PERIOD WILL
END WITH BELOW NORMAL TEMPERATURES AND DRY WEATHER.
&&

.LONG TERM...MONDAY THROUGH THURSDAY
HIGH PRESSURE WILL BE OVER THE REGION TO BEGIN THE LONG
TERM...BRINGING DRY WEATHER AND MILD CONDITIONS. NORTHWEST FLOW
ALOFT WILL BRING WEAK DISTURBANCES THROUGH THE FLOW...BUT WILL ONLY
NOTICE AN INCREASE IN CLOUD COVER. A WARM FRONT WILL MOVE THROUGH
THE STATE ON THURSDAY...BUT WITH LIMITED MOISTURE...HAVE NOT
INCLUDED ANY POPS AT THIS TIME.
&&

.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR     44  52  35  42 /  50  40  30  40
CAMDEN AR         60  61  42  53 /  70  80  60  20
HARRISON AR       38  51  30  37 /  50  20  30  30
HOT SPRINGS AR    55  58  39  51 /  70  70  50  20
LITTLE ROCK   AR  54  56  39  47 /  70  70  50  30
MONTICELLO AR     60  63  43  46 /  80  80  70  20
MOUNT IDA AR      55  57  37  49 /  70  60  50  10
MOUNTAIN HOME AR  38  51  34  38 /  50  30  30  40
NEWPORT AR        45  53  35  42 /  50  40  40  40
PINE BLUFF AR     56  60  42  47 /  80  80  60  20
RUSSELLVILLE AR   49  56  39  48 /  60  40  30  20
SEARCY AR         52  55  41  44 /  60  60  40  30
STUTTGART AR      54  57  40  44 /  80  80  60  30
&&

.LZK WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR 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.
&&

SHORT TERM...57 / LONG TERM...58

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LITTLE ROCK AR
545 PM CST THU FEB 26 2009

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-271100-
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-
545 PM CST THU FEB 26 2009

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

.DAY ONE...TONIGHT

A SLIGHT RISK OF STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS THE
AREA TONIGHT. A STORM SYSTEM WILL MOVE ACROSS THE CENTRAL PLAINS...
AND SAG A COLD FRONT INTO ARKANSAS THURSDAY EVENING AND INTO THE
OVERNIGHT HOURS. WITH INCREASED MOISTURE AND INSTABILITY...SHOWERS
AND THUNDERSTORMS WILL DEVELOP. ISOLATED STRONG TO SEVERE STORMS
WILL BE POSSIBLE AHEAD AND ALONG THE COLD FRONT. THE MAIN RISK WILL
BE DAMAGING WINDS AND LARGE HAIL. THE TORNADO RISK IS LOW AT THIS
TIME BUT AN ISOLATED ONE WILL BE POSSIBLE. WINDS WILL ALSO BE
ELEVATED ACROSS THE ENTIRE AREA. ISOLATED AREAS OF HEAVY RAIN WILL
ALSO BE A CONCERN LATE TONIGHT IN THE CENTRAL AND SOUTHERN SECTIONS
OF ARKANSAS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

AS THE FRONT SLOWLY MOVES SOUTH...THE SEVERE THREAT WILL MOVE INTO
THE SOUTH PART OF THE STATE FOR FRIDAY. HEAVY RAIN WILL ALSO BE
POSSIBLE IN THE CENTRAL AND SOUTH SECTIONS EARLY FRIDAY. A COUPLE OF
LIMITING FACTORS WILL BE THE TIME OF DAY THE FRONT WILL MOVE
THROUGH...AND THE STRONGEST DYNAMICS WILL BE NORTH OF ARKANSAS.
SHOWERS AND THUNDERSTORMS WILL BE LIKELY FRIDAY. MAINLY DRY AND
COOLER AIR IS EXPECTED OVER THE WEEKEND...AS HIGH PRESSURE WILL MOVE
INTO THE AREA. THESE CONDITIONS WILL CONTINUE INTO EARLY NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT AND FRIDAY.

&&

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

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