Flash Flooding and Hail in Arkansas, May 8 to 10, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
646 AM CDT FRI MAY 8 2009

.AVIATION...
A SLOW MOVING COLD FRONT IN OKLHAOMA WILL CONTINUE TO WORK ITS WAY
TOWARD ARKANSAS. THUNDERSTORM CHANCES WILL INCREASE TODAY FROM
NORTHWEST TO CENTRAL ARKANSAS. WILL HOLD OFF ON RAIN CHANCES AT
LLQ TIL 05Z. THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS
ACROSS THE AREA TODAY AND TONIGHT. SOME OF THE THUNDERSTORMS WILL
PRODUCE HEAVY RAINFALL. RAIN CHANCES WILL CONTINUE THROUGH THE
WEEKEND. VFR TO MVFR CONDITIONS WILL PERSIST TODAY AND TONIGHT.

&&

.PREV DISCUSSION... /ISSUED 335 AM CDT FRI MAY 8 2009/

DISCUSSION...
MAIN CONCERNS THIS FORECAST CYCLE ARE CHANCES OF RAIN ALMOST EVERY
DAY. WHICH DAYS WILL HAVE GREATEST CHANCE AND ANY SEVERE WEATHER
AND FLASH FLOODING POTENTIAL. DENSE FOG AND ELEVATED WINDS TODAY A
MINOR ISSUED.

STATIONARY BOUNDARY OVER NORTHERN MO...WITH MCS MOVING SE OVER
SOUTHEAST MO. ALSO OUT WEST...ANOTHER SHORTWAVE PUSHING ACROSS
WESTERN KS AND DEVELOPING CONVECTION. ATMOSPHERE OVER AR REMAINS
QUITE WARM...MOIST AND UNSTABLE...WITH SURFACE TEMPS IN THE UPPER
60S TO MID 70S...WHILE DEW POINT TEMPS FROM THE MID 60S TO MID
70S. HAVE SEEN PATCHY FOG FORMING...BUT AT THIS TIME DO NOT EXPECT
ADVISORY CONDITIONS. PRECIP WATER VALUES FROM ONE TO AROUND 1.5
INCHES OVER THE STATE...AND ANY CONVECTION WILL PRODUCE HEAVY RAIN.
WILL ISSUE FLASH FLOOD WATCH FOR NORTH AND CENTRAL AR TODAY THROUGH
SATURDAY EVENING.

MCS PUSHING ACROSS WESTERN KS WILL MOVE EAST TO SOUTHEAST...AND
NOT SURE HOW FAR SOUTH IT WILL GO. DO HAVE POPS THIS MORNING...
BUT MAY HAVE TO FINE TUNE POPS EARLY THIS MORNING BASED ON TRENDS.

SHORT TERM...TODAY THROUGH MONDAY NIGHT
MODELS ARE FORECASTING MCS ACTIVITY TODAY TO THIS EVENING...THEN
THE COLD FRONT TO SAG INTO AR FOR SATURDAY. THERE ARE DIFFERENCES
IN THE DETAILS IN WHERE THE MAIN SURGE OF ENERGY WILL GO...AND THE
POTENTIAL FOR ISOLATED STRONG TO SEVERE STORMS. MODELS TAKE TODAYS
ENERGY SURGE MAINLY OVER MO TO FAR NORTHERN AR...WITH SOME LOW
LEVEL JET ENHANCEMENT INTO NORTHERN AR. DID ADD HEAVY RAIN AND
ISOLATED STRONG TO SEVERE STORMS POSSIBLE. SPC SLIGHT RISK COVERS
ALL OF AR. FRIDAY NIGHT TO SATURDAY...FRONT SAGS OVER NORTHERN TO
CENTRAL...WITH MAIN FOCUS OF CONVECTION OVER NORTH AND CENTRAL.
LOW LEVEL JET WEAKENS OVER AR ON SATURDAY...BUT PRECIP WATER
VALUES REMAIN AROUND 1 TO 1.5 INCHES. HEAVY RAIN STILL EXPECTED TO
LOCALIZED FLASH FLOODING. SATURDAY NIGHT TO SUNDAY...THE BOUNDARY
STALLS OVER CENTRAL AR...AS THE UPPER FLOW REMAINS ZONAL. MODELS
SHOW SOME SHORTWAVE ENERGY MOVING ACROSS THE AREA. ECMWF KEEPS
MOST OF ENERGY NORTH OF AR...SO GFS AND NAM SOLUTIONS USED. SUNDAY
CONTINUES THE THREAT OF RAIN OVER THE NATURAL STATE...WITH AREAS
OF HEAVY RAIN. MODELS SAG THE COLD FRONT TO NORTHERN LA TO
SOUTHERN AR...SO EXPECT HIGH POPS TO FOCUS OVER THOSE AREAS ON
MONDAY. OTHERWISE...TEMPS REMAIN AT OR ABOVE NORMAL VALUES TODAY.
COOLER SATURDAY TO MONDAY AS THE BOUNDARY SAGS THROUGH AR.

LONG TERM...TUESDAY THROUGH THURSDAY
NORTHWEST FLOW WILL BE OVER THE AREA TO BEGIN THE PERIOD WITH AN
UPPER RIDGE APPROACHING FROM THE WEST. THIS RIDGE WILL DRIFT INTO
THE APPALACHIANS WEDNESDAY AND SOUTHWEST FLOW WILL RETURN TO
ARKANSAS. AN UPPER TROUGH WILL THEN MOVE THROUGH THE AREA
THURSDAY.

LATEST MODELS ARE IN GOOD AGREEMENT IN THE EXTENDED PERIOD. SURFACE
HIGH PRESSURE WILL BE OVER THE OHIO RIVER VALLEY TO BEGIN THE
PERIOD. WILL KEEP SLIGHT CHANCE POPS OVER THE SOUTHWEST WHERE MORE
MOISTURE WILL BE PRESENT. A STATIONARY FRONT WILL BE OVER THE AREA
WEDNESDAY. LOW PRESSURE WILL BRING A COLD FRONT ACROSS THE AREA
THURSDAY. WILL BRING AN INCREASE IN RAIN CHANCES IN FOR THURSDAY
ACROSS THE AREA. HIGHEST QPF WILL BE ON THURSDAY AND THURSDAY NIGHT.
NEAR NORMAL TEMPERATURES ARE EXPECTED THROUGH THE PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR     81  63  69  54 /  60  70  60  50
CAMDEN AR         91  68  77  60 /  20  40  50  50
HARRISON AR       76  59  67  47 /  70  70  50  40
HOT SPRINGS AR    86  67  76  59 /  30  50  60  60
LITTLE ROCK   AR  86  67  74  57 /  30  50  60  60
MONTICELLO AR     89  69  79  62 /  20  30  40  50
MOUNT IDA AR      85  65  72  55 /  30  60  60  60
MOUNTAIN HOME AR  77  59  67  50 /  70  70  50  40
NEWPORT AR        82  64  70  54 /  60  70  60  50
PINE BLUFF AR     88  67  80  58 /  30  40  50  50
RUSSELLVILLE AR   81  64  69  55 /  50  70  60  50
SEARCY AR         85  64  71  58 /  40  60  60  60
STUTTGART AR      86  67  74  57 /  30  50  60  60
&&

.LZK WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR BAXTER-BOONE-
CLEBURNE-CONWAY-FAULKNER-FULTON-GARLAND-INDEPENDENCE-IZARD-
JACKSON-JOHNSON-LOGAN-LONOKE-MARION-MONROE-MONTGOMERY-NEWTON-
PERRY-POLK-POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-
VAN BUREN-WHITE-WOODRUFF-YELL.

&&

AVIATION...51

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
808 AM CDT FRI MAY 8 2009

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-091000-
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-
808 AM CDT FRI MAY 8 2009

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

.DAY ONE...TODAY AND TONIGHT

A LARGE COMPLEX OF THUNDERSTORMS WILL CONTINUE MOVING THROUGH
NORTHERN ARKANSAS AND SOUTHERN MISSOURI THIS MORNING AND INTO THE
AFTERNOON HOURS. STORMS WILL SHIFT FURTHER SOUTH INTO ARKANSAS BY
THIS AFTERNOON. SOME STORMS WILL BECOME SEVERE...PRODUCING LARGE
HAIL AND DAMAGING WIND GUSTS. AN ISOLATED TORNADO MAY OCCUR AS WELL.
ANY STRONGER STORMS WILL HAVE THE CAPABILITY OF PRODUCING LOCALLY
HEAVY RAINFALL...GREATER THAN ONE INCH PER HOUR.

ALSO...AFTER THE STORMS MOVE THROUGH...SHARP PRESSURE DIFFERENCES
BETWEEN THE STORMS AND HIGHER PRESSURE TO THE WEST COULD CAUSE GUSTY
WINDS TO OCCUR...PRIMARILY ACROSS NORTHERN ARKANSAS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THE AFOREMENTIONED FRONT IS FORECAST TO MEANDER OVER ARKANSAS
THROUGH THE WEEKEND. MEANWHILE...A SERIES OF UPPER LEVEL IMPULSES
WILL PASS ACROSS THE REGION...PRODUCING SEVERAL ROUNDS OF SHOWERS
AND THUNDERSTORMS OVER THE STATE. THE POTENTIAL FOR SEVERE STORMS
AND HEAVY RAINFALL WILL CONTINUE AS WELL.

RAINFALL AMOUNTS OF TWO AND FOUR INCHES IS FORECAST FOR MUCH OF
ARKANSAS FRIDAY THROUGH SUNDAY...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. WITH THE HEAVY RAINFALL OVER THE PAST FEW DAYS...THE
GROUND IS ALREADY SATURATED ACROSS A LARGE PART OF THE STATE. ANY
ADDITIONAL HEAVY RAINFALL WILL ONLY INCREASE THE THREAT OF FLASH
FLOODING.

THE FRONT WILL PUSH SOUTH OF ARKANSAS EARLY NEXT WEEK...ALLOWING
HIGH PRESSURE TO BRIEFLY BUILD INTO THE AREA. THE HIGH WILL QUICKLY
SHIFT EASTWARD BY TUESDAY...ALLOWING THE FRONT TO LIFT BACK
NORTHWARD THROUGH THE STATE. ISOLATED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE...BUT THE CHANCES OF ORGANIZED SEVERE WEATHER WILL BE LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE POSSIBLE TODAY AND CONTINUING THROUGH THE
WEEKEND.

&&

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

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