Tornado and Hail in Arkansas, October 24 to 26, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1126 AM CDT SUN OCT 24 2010

.UPDATE...

A BIT OF A DIFFICULT FCST THIS AFTERNOON AS LOW...MID...AND HIGH
CLOUDS ARE PREVENTING MUCH IN THE WAY OF INSOLATION AND SUBSEQUENT
DESTABILIZATION. THAT SAID...IT MAY NOT TAKE SUBSTANTIAL HEATING
TO DEVELOP MODEST INSTABILITY AS MID LVL COOLING OVERSPREADS THE
STATE LATE THIS AFTERNOON WHILE AT THE SAME TIME SFC DEWPTS SURGE
TOWARD 70F. ATTM...IT APPEARS THE BEST THREAT FOR SVR WX WILL BE
OVER SRN AR...THOUGH AN ISOLATED SVR STORM CANNOT BE RULED OUT
OVER CEN AND NRN AR.

UPWARD VERTICAL MOTION AHEAD OF A CYCLONICALLY CURVED JET STREAK IS
CONTINUING TO IMPACT MAINLY SERN PARTS OF THE CWA WITH SHOWERS AND A
FEW THUNDERSTORMS SEEN IN THESE AREAS. A MORE SUBSTANTIAL SHRTWV
WILL DIG TOWARD THE STATE LATE THIS AFTERNOON. THIS SHRTWV SHOULD
FIRE STORMS LATE THIS AFTERNOON IN A CORRIDOR OF 1000-2000 J/KG
MLCAPE. THE MOST LIKELY LOCATION FOR THIS INITIATION WILL BE FROM
ARKADELPHIA SWWD. LACK OF WELL DEFINED LOW LVL FOCUS/FORCING
MECHANISM MAY RESULT IN DISCRETE OR QUASI-DISCRETE STORM MODE
INITIALLY BEFORE STRONGER UPR FORCING PROVIDES IMPETUS FOR STORMS
TO CONGEAL INTO AN MCS THAT WOULD MOVE THROUGH SRN AR AND NRN LA
THIS EVE.

DEPENDING ON INITIATION AND STORM MODE...A SMALL WINDOW OF A
CONDITIONAL TORNADO THREAT MAY DEVELOP FROM ABOUT 5-9PM THIS EVE IN
SRN AR AS INCREASING SYNOPTIC SCALE ASCENT COMBINES WITH BACKING OF
SFC WINDS AND NOCTURNAL ENHANCEMENT OF THE LLJ DUE TO INITIAL
DECOUPLING. AFTER ABOUT 9PM CDT...WITH THE PBL MOSTLY DECOUPLED...
SBCIN WILL RAPIDLY INCREASE AND ALL INSTABILITY WILL QUICKLY
BECOME ELEVATED...DECREASING ANY TORNADO THREAT.

ANY SVR WX SHOULD BE ON THE WANE BY MIDNIGHT WITH LINGERING SHOWERS
OUT OF THE CWA BY DAYBREAK MON.

WILL BE REDUCING HIGH TEMPS A BIT TODAY IN PARTS OF W CEN AND NRN
AR AS LOW STRATUS IS SHOWING LITTLE SIGN OF BREAKING UP.

UPDATED GRIDS/ZONES WILL BE OUT SOON.

&&

.PREV DISCUSSION... /ISSUED 628 AM CDT SUN OCT 24 2010/

AVIATION...
SEVERAL WAVES WILL MOVE ACROSS THE STATE IN THE NEXT 24 HOURS...AND
TIMING WILL BE AN ISSUE. FIRST WAVE CURRENTLY MOVING EAST WILL
KEEP VCSH AT THE SOUTHERN SITES THROUGH MID MORNING. STRATUS HAS
BEEN MOVING EAST THROUGH THE NIGHT...AND WILL KEEP TEMPO GROUPS
FOR IFR CONDITIONS THROUGH 15Z...BEFORE GUSTY SOUTH WINDS HELP
LIFT THE CLOUDS. ANOTHER WAVE WILL MOVE THROUGH DURING THE
AFTERNOON. HAVE TRIED TO TIME THIS WAVE...AND HAVE VCTS AND TEMPO
GROUPS FOR TSRA. AT KPBF AND KLLQ...HAVE TSRA PREVAILING AS MOST
ENERGY WILL BE ACROSS THIS AREA.

PREV DISCUSSION... /ISSUED 316 AM CDT SUN OCT 24 2010/

SHORT TERM...TODAY THROUGH WEDNESDAY
EARLY THIS MORNING...WATER VAPOR IMAGERY SHOWS A CLEARLY DEFINED
UPPER TROUGH CURRENTLY COMING OFF THE SOUTHERN ROCKIES IN THE
VICINITY OF EASTERN NEW MEXICO AND FAR WEST TEXAS. THIS SYSTEM IS
GOING TO COME INTO PLAY IN OUR AREA THIS AFTERNOON AND EVENING.

AT THE SURFACE...HIGH PRESSURE WAS OVER THE SOUTHEAST CONUS...
WHILE LOW PRESSURE CONTINUED TO DEVELOP OUT IN THE PLAINS. THE
CLOSE PROXIMITY OF THESE TWO SYSTEMS WILL ALLOW FOR GUSTY WINDS
OVER THE AREA TODAY...SO HAVE ONCE AGAIN GONE WITH A LAKE WIND
ADVISORY FOR THE ENTIRE FORECAST AREA. THIS WILL LIKELY BE NEEDED
AGAIN ON MONDAY...AS WINDS WILL BE A LITTLE STRONGER.

AREA WILL BE DEALING WITH TWO SYSTEMS TODAY. THE FIRST AND WEAKER
ONE WILL BE COMING UP FROM NORTHEAST TEXAS LATER THIS MORNING.
RADAR RETURNS AND SATELLITE IMAGERY SHOW CONVECTION DEVELOPING
INVOF NORTHEAST TEXAS AND WESTERN LOUISIANA. AS THE SYSTEM MOVES
NORTHEAST...ADDITIONAL SHOWERS AND STORMS WILL DEVELOP AND MOVE
THROUGH SOUTHEAST ARKANSAS.

THE SECOND AND MORE POTENT SYSTEM WILL MOVE EAST FROM THE ROCKIES
THIS MORNING AND INTO EAST TEXAS BY THE AFTERNOON. SHOWERS AND
THUNDERSTORMS WILL DEVELOP BY MID TO LATE AFTERNOON ACROSS WEST
CENTRAL AND SOUTHWEST ARKANSAS AND SPREAD NORTHEAST DURING THE
EVENING HOURS.

SOME STORMS COULD BE SEVERE. HAIL AND WINDS WILL BE THE PRIMARY
THREAT WITH ANY SEVERE STORMS. WITH INCREASING LOW LEVEL SHEAR...
CAN/T RULE OUT A TORNADO. THE BIG LIMITING FACTOR WILL BE IF THE
AREA CAN SUFFICIENTLY DESTABILIZE...GIVEN EXPECTED CLOUD COVER...
AND HOW MUCH THE EARLIER SYSTEM WORKED OVER THE AIRMASS.

THE UPPER TROUGH WILL PUSH THROUGH LATE TONIGHT...GIVING THE
REMAINING MOISTURE/PRECIP A SHOVE OFF TO THE EAST. ANY LINGERING
RAIN WILL BE ENDING BY EARLY MONDAY MORNING.

A STRONGER UPPER TROUGH ASSOCIATED WITH AN UPPER LOW DIVING
SOUTHEAST INTO THE DAKOTAS FROM CANADA WILL BE ENOUGH TO SEND A
COLD FRONT OUT IN THE PLAINS INTO THE AREA. SHOWERS AND
THUNDERSTORMS WILL AGAIN BE POSSIBLE MONDAY NIGHT AND INTO TUESDAY...
AS THE FRONT AND UPPER TROUGH PASS ACROSS THE AREA. HOWEVER...
MOISTURE RETURN AHEAD OF THE FRONT IS A BIG QUESTION MARK...AND AS
SUCH...DON/T EXPECT WIDESPREAD PRECIP WITH IT.

SLIGHTLY COOLER AIR WILL FOLLOW THE FRONT.

LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY
NORTHWEST FLOW AND HIGH PRESSURE WILL BRING COOLER AND DRIER
CONDITIONS TO THE STATE. AS THE SURFACE HIGH MOVES SOUTHEAST LATE IN
THE WEEK...TEMPERATURES WILL BEGIN A WARMING TREND...BUT THE UPPER
RIDGE SHOULD KEEP CONDITIONS DRY.

&&

.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR     78  60  80  60 /  30  50  10  30
CAMDEN AR         86  63  83  69 /  50  60  10  30
HARRISON AR       76  57  78  55 /  20  30  10  40
HOT SPRINGS AR    81  62  79  63 /  50  50  10  30
LITTLE ROCK   AR  83  63  81  68 /  50  60  10  30
MONTICELLO AR     84  65  86  72 /  50  70  10  30
MOUNT IDA AR      80  60  79  60 /  40  50  10  30
MOUNTAIN HOME AR  79  57  81  57 /  30  40  10  40
NEWPORT AR        81  63  81  63 /  40  60  10  30
PINE BLUFF AR     82  62  83  69 /  60  70  10  30
RUSSELLVILLE AR   80  59  80  58 /  40  40  10  30
SEARCY AR         80  58  81  62 /  40  60  10  30
STUTTGART AR      82  63  83  67 /  50  70  10  30
&&

.LZK WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 7 PM CDT 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.

&&

UPDATE...63

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LITTLE ROCK AR
500 AM CDT SUN OCT 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-
500 AM CDT SUN OCT 24 2010

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

.DAY ONE...TODAY AND TONIGHT

A LARGE STORM SYSTEM OVER THE SOUTHERN PLAINS WILL SEND SEVERAL
WAVES OF LOW PRESSURE INTO ARKANSAS. SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER THE STATE THIS MORNING...AS THE
FIRST WAVE MOVES THROUGH.

A SECOND...STRONGER WAVE WILL MOVE ACROSS THE STATE THIS
AFTERNOON...AND INTERACT WITH THE HEATING OF THE DAY. SHOWERS AND
THUNDERSTORMS WILL BE MOST LIKELY ACROSS THE SOUTHEAST HALF OF THE
STATE. THIS AREA...OR SOUTH AND EAST OF A LINE FROM MOUNTAIN
HOME...TO LITTLE ROCK...TO ARKADELPHIA...HAS THE BEST CHANCE FOR
SEVERE WEATHER DURING THE AFTERNOON INTO THE EVENING HOURS. THE MAIN
CONCERNS WILL LARGE HAIL AND DAMAGING WINDS. HOWEVER...ISOLATED
TORNADOES CAN NOT BE RULED OUT...AS WINDS ABOVE THE SURFACE WILL BE
TURNING WITH HEIGHT.

BREEZY WINDS WILL ALSO BE POSSIBLE TODAY...AS SOUTH WINDS OF 15 TO
25 MPH...WITH HIGHER GUSTS...WILL OCCUR. A LAKE WIND ADVISORY HAS
BEEN ISSUED FOR THE ENTIRE AREA.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THERE WILL BE A BREAK IN THE RAIN CHANCES DURING THE DAY MONDAY...AS
THE MAIN PART OF THE SYSTEM MOVES EAST. HOWEVER...THE COLD FRONT
ASSOCIATED WITH THE SYSTEM WILL MOVE THROUGH ARKANSAS LATE
MONDAY NIGHT INTO TUESDAY...BRINGING SHOWER AND THUNDERSTORM CHANCES
BACK TO THE STATE.

DRY WEATHER WILL FOLLOW THIS FRONT...ALONG WITH MUCH COOLER
TEMPERATURES...FOR THE REMAINDER OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING ACROSS
THE SOUTHEAST HALF OF THE STATE.

&&

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

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