Tornado and Damaging Wind in Arkansas, April 15, 2012

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1239 PM CDT SUN APR 15 2012

.DISCUSSION...

UPDATED FOR 18Z AVIATION DISCUSSION BELOW...

&&

.AVIATION...

CLOUD COVER CONTINUES ACROSS MUCH OF AR AS MOISTURE STREAMS NORTH
AHEAD OF THE APPROACHING COLD FRONT. SOME SPOTS ARE OCCASIONALLY
SEEING MVFR CIGS WITH STRATOCU MOVING OVERHEAD. THE MAIN IMPACTS
OTHER THAN THESE OCCASIONAL MVFR CIGS EARLY THIS AFTERNOON WILL
BE THE BREEZY SRLY WINDS. EXPECT WINDS OF 12-18 KTS
SUSTAINED...AND GUSTS OVER 30 KTS POSSIBLE IN SOME LOCATIONS.

LINE OF THUNDERSTORMS WILL MOVE EAST FROM OK THIS AFTERNOON INTO
THE EVENING HRS...IMPACTING NRN AND WRN AR FIRST MID TO LATE
AFTERNOON...THEN LATE THIS AFTERNOON INTO THE EVENING HRS ACROSS
CENTRAL SECTIONS. THUNDERSTORM ACTIVITY SHOULD HOLD OFF UNTIL MID
TO LATE EVENING FOR THE SERN SITES AS THE FRONT MOVES CLOSER TO
THAT PART OF THE STATE. EXPECT GENERALLY MVFR CONDITIONS WITH THE
TSRA...BUT SOME LOCATIONS WILL LIKELY SEE WORSE CONDITIONS UNDER
THE STRONGER STORMS.

EXPECT WINDS TO SHIFT TO THE WEST AND NW BEHIND THE FRONT DURING
THE MORNING HRS ON MON...WITH IMPROVING CONDITIONS EXPECTED.

&&

PREV DISCUSSION... /ISSUED 345 AM CDT SUN APR 15 2012/

SHORT TERM...TODAY THROUGH WEDNESDAY

AT THE SURFACE THIS MORNING...A COLD FRONT EXTENDED DOWN FROM A
SURFACE LOW OVER EASTERN NEBRASKA INTO FAR WEST TEXAS...WITH AN
ACCOMPANYING DRYLINE DOWN INTO THE BIG BEND AREA. IN THE UPPER
LEVELS...A LOW PRESSURE SYSTEM WAS LOCATED OVER THE CENTRAL
ROCKIES...WITH A LONGWAVE TROUGH EXTENDING DOWN TO BAJA
CALIFORNIA.

AFOREMENTIONED LOW AND ASSOCIATED TROUGH WILL PUSH THE COLD FRONT
TOWARD THE REGION TODAY. SHOWERS/STORMS WILL DEVELOP AHEAD OF THE
FRONT LATER THIS MORNING...AND THE CONVECTION WILL PUSH INTO
NORTHWEST/WESTERN ARKANSAS BY MID DAY.

WINDS TODAY WILL REMAIN HIGH DUE TO THE GRADIENT BETWEEN THE
APPROACHING LOW PRESSURE AND FRONT AND A SURFACE HIGH OVER THE
SOUTHEAST CONUS. WILL CONTINUE THE LAKE WIND ADVISORY...WITH
SUSTAINED WINDS OF 20 TO 30 MPH AND GUSTS APPROACHING 40 MPH.

SOME STORMS THAT DEVELOP TODAY...IN PARTICULAR THIS AFTERNOON AND
TONIGHT...WILL BE SEVERE. SEVERE STORMS MOST LIKELY WILL BE OF
THE BOW-ECHO TYPE...WITH DAMAGING WIND GUSTS IN EXCESS OF 70 MPH
POSSIBLE. THERE WILL ALSO BE MICROBURST POTENTIAL IN ANY DISCRETE
CELLS THAT DEVELOP OUT AHEAD OF THE MAIN LINE. LARGE HAIL CANNOT
BE RULED OUT AS WELL...BUT WILL LIKELY BE TOWARD THE LOW-END
SEVERE CRITERIA.

AN ISOLATED TORNADO IS POSSIBLE...ESPECIALLY IF CELLS CAN DEVELOP
OUT AHEAD OF THE MAIN LINE. THE THREAT WOULD BE INCREASED IF
SURFACE WINDS CAN MANAGE TO BACK TO THE SOUTHEAST AHEAD OF THE
LINE AS WELL...WHICH WOULD ACT TO ENHANCE THE POTENTIAL FOR
ROTATING UPDRAFTS.

HIGH PRECIPITABLE WATER VALUES AND GOOD JET DYNAMICS WILL ALLOW
FOR SOME STRONGER STORMS TO PRODUCE LOCALIZED HEAVY RAINFALL.
HOWEVER...THE THREAT WILL NOT BE WIDESPREAD...AS 0-6 KM STORM
MOTION WILL TEND TO BE AT OR ABOVE 30 KNOTS.

BEST TIMING FOR SHOWERS AND THUNDERSTORMS LOOKS TO BE WEST OF A
MOUNTAIN HOME TO LITTLE ROCK TO TEXARKANA LINE BEFORE 00Z...AND
MOSTLY EAST OF THE LINE AFTER THAT. CONVECTION MAY DIMINISH AFTER
MIDNIGHT...HOWEVER THERE COULD BE SOME RE-FIRING OF CELLS ALONG
AND EAST OF THE I-30 CORRIDOR AFTER MIDNIGHT AS THE LOW-LEVEL JET
KICKS IN.

PRECIP WILL WIND DOWN ON MONDAY...AS THE FRONT PUSHES THE
REMAINING MOISTURE TO THE EAST OF THE REGION. DRIER AND SLIGHTLY
COOLER WEATHER WILL BE NOTED THROUGH THE END OF THE PERIOD AS HIGH
PRESSURE MOVES ACROSS THE REGION.

LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY

ZONAL FLOW ALOFT BEGINS THE PERIOD OVER MUCH OF THE COUNTRY.
HOWEVER AN UPPER LEVEL TROUGH DEVELOPS IN THE NORTHERN PLAINS
FRIDAY AND MOVES THROUGH THROUGH ARKANSAS LATE FRIDAY AND EARLY
SATURDAY. A LARGE UPPER RIDGE DEVELOPS OVER THE WEST SATURDAY AND
NORTHWEST FLOW WILL RETURN TO ARKANSAS.

A COLD FRONT IN THE PLAINS THURSDAY WILL MOVE THROUGH ARKANSAS
FRIDAY. THIS WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
AREA. ABOVE NORMAL TEMPERATURES ARE EXPECTED THURSDAY...BUT COOLER
AIR BEHIND THE FRONT WILL BRING BELOW NORMAL TEMPERATURES TO THE
AREA FRIDAY AND SATURDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR     79  52  72  49 /  70  80  10  10
CAMDEN AR         83  58  80  55 /  80  90  20  10
HARRISON AR       74  49  70  46 /  60  60  10  10
HOT SPRINGS AR    78  56  79  54 /  70  80  10  10
LITTLE ROCK   AR  82  59  78  55 /  80  80  10  10
MONTICELLO AR     85  64  80  58 /  70  80  30  10
MOUNT IDA AR      77  53  77  48 /  70  70  10  10
MOUNTAIN HOME AR  78  51  73  46 /  70  70  10  10
NEWPORT AR        79  55  73  49 /  70  90  20  10
PINE BLUFF AR     82  62  78  56 /  70  90  20  10
RUSSELLVILLE AR   77  52  75  48 /  70  70  10  10
SEARCY AR         79  56  76  46 /  70  90  20  10
STUTTGART AR      81  60  77  53 /  70  90  20  10
&&

.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.

&&

AVIATION...62

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1235 PM CDT SUN APR 15 2012

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-161000-
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-
1235 PM CDT SUN APR 15 2012

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

A LINE OF SHOWERS AND THUNDERSTORMS WAS ENTERING WESTERN ARKANSAS
AS OF 1230 PM CDT. THERE WAS ISOLATED SEVERE WEATHER ALONG THE
LINE...WITH SEVERE STORMS EXPECTED TO BECOME A LITTLE MORE NUMEROUS
HEADING THROUGH THE AFTERNOON. STORM INTENSIFICATION WILL BE DUE TO
INCREASING MOISTURE AND HEATING AHEAD OF THE LINE.

THE LINE OF STORMS IS EXPECTED TO EXTEND FROM YELLVILLE TO
RUSSELLVILLE AND TEXARKANA BY 300 PM CDT...AND FROM HARDY TO LITTLE
ROCK AND EL DORADO BY 600 PM CDT. STORMS WILL SURGE INTO EASTERN
ARKANSAS THIS EVENING.

THE MAIN CONCERN WITH THE STORMS WILL BE STRONG TO DAMAGING WINDS.
WIND GUSTS COULD EXCEED 70 MPH IN PLACES. A FEW STORMS COULD PRODUCE
QUARTER SIZE HAIL OR LARGER. ALSO...WINDS AHEAD OF THE LINE OF
STORMS WILL BE FROM THE SOUTH OR SOUTHEAST...WITH SOUTHWEST WINDS
ALOFT. WINDS WILL TURN WITH HEIGHT...CREATING ROTATION AND THE
POSSIBILITY OF ISOLATED TORNADOES.

AREAS OF BRIEF HEAVY RAIN ARE LIKELY...BUT ANY FLASH FLOODING WILL
BE LOCALIZED. RAINFALL AMOUNTS WILL AVERAGE ONE HALF TO ONE AND A
HALF INCHES...WITH LOCALLY OVER TWO INCHES.

IT WILL BE WINDY AHEAD OF THE STORMS. WIND SPEEDS OF 20 TO 30 MPH
WILL BE COMMON TODAY...WITH GUSTS UP TO 40 MPH POSSIBLE. AS A
RESULT...A LAKE WIND ADVISORY IS IN EFFECT FOR A LARGE PART OF THE
NATURAL STATE THROUGH THIS EVENING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

SHOWERS AND STORMS WILL EXIT THE REGION ON MONDAY WITH A COLD FRONT.
HIGH PRESSURE WILL SETTLE INTO THE AREA BEHIND THE FRONT FOR A FEW
DAYS. CHANCES OF SHOWERS AND THUNDERSTORMS WILL RETURN FRIDAY AND
SATURDAY AS ANOTHER COLD FRONT ARRIVES FROM THE PLAINS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THIS AFTERNOON AND EVENING AS THE
SEVERE WEATHER POTENTIAL INCREASES.

&&

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

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