Severe Thunderstorm Warning 40, NWS Little Rock, AR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
725 AM CST FRI FEB 18 2000

...UPDATED SECTION...
13Z OBSERVATIONS INDICATE WARM FRONT HAS MOVED QUICKLY ACROSS THE NORTHERN
PART OF THE STATE.  THIS HAS RESULTED IN A GOOD DEAL OF TEMPERATURE
DIFFERENCE BETWEEN THE NORTHERN RIDGES AND VALLEYS WITH HARRISON AT
66 DEGREES...WHILE FLIPPIN AT 46 AND MOUNTAIN HOME AT 44 DEGREES.
I THEREFORE HAVE INCREASED THE MAX TEMPERATURES TODAY ACROSS THE
NORTH.  AFTER LOOKING AT THE 13Z OBSERVATIONS...I HAVE ALSO DECIDED
TO INCREASE THE TEMPERATURES ACROSS THE REMAINDER OF THE REGION.

..PREVIOUS AFD...
AN AREA OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS EASTERN
OKLAHOMA AND WESTERN ARKANSAS. THESE THUNDERSTORMS HAVE MOVED INTO
THE WESTERN AND NORTHERN PART OF MY CWFA. SPC HAS DROPPED A WATCH
FOR MY ENTIRE CWFA UNTIL 11 AM. UPDATED THE ZONES TO INCLUDE THIS
WATCH. LOOKS THE MAIN SEVERE WEATHER THREAT WILL BE DAMAGING WINDS.
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO CONTINUE ALONG OR OUT
AHEAD OF THE FRONT AND I HAVE INCLUDED A SLIGHT CHANCE POP ACROSS
SOUTHEAST FOR THIS EVENING. OTHERWISE...CONDITIONS WILL BE DRY AND
COLDER AIR WILL WORK IN.
OTHERWISE...NO OTHER CHANGES.

LATEST 11.0-3.9 MICRON (LOW CLOUD/FOG) IMAGERY INDICATES FOG AND
CLOUDS BREAKING UP ACROSS THE SOUTHERN AND WESTERN PART OF MY
CWFA...AS THE WARM FRONT MOVE THROUGH THE STATE.  06Z SURFACE
ANALYSIS HAD THE SURFACE LOW LOCATED JUST TO THE NORTH OF KOKC WITH
ONE WARM FRONT EXTENDING NORTHEASTWARD TO JUST NORTH KSTL. THIS WARM
FRONT SEPARATES THE REALLY COLD AIR (WINTRY TYPE) VS MORE EARLY
SPRING-LIKE WEATHER. A SECOND WARM FRONT EXTENDED FROM THE LOW
THROUGH CENTRAL AR AND THEN BACK INTO CENTRAL TN. A DRY LINE EXTENDS
FROM SOUTH CENTRAL OK AND INTO WEST TX WITH THE COLD FRONT ACROSS
THE TX PANHANDLE.

IN THE UPPER LEVELS...THE MAIN TROUGH AND SHORT WAVE WERE LOCATED
ACROSS EASTERN CO WITH AR IN SOUTHWESTERLY FLOW AND ZONAL FLOW
ACROSS MUCH OF THE REST OF THE COUNTRY. A SECOND TROUGH WAS ALSO
LOCATED ACROSS THE WEST COAST.

THE MODELS ALL INITIALIZED WELL...COMPARING TO THE LATEST WV VAPOR
IMAGERY. SOME DIFFERENCES IN THE MODELS WILL DEVELOP IN TIME...BUT
THE OVERALL SYNOPTIC PATTERNS ARE SIMILAR. I WILL LEAN CLOSER TOWARD
THE AVN...BUT ALL MODELS LOOK GOOD.

THE MAIN TROUGH AND SHORT WAVE WILL WEAKEN AND SHEAR OUT...AS IT
MOVES TO THE EAST ACROSS SOUTHERN MO AND INTO THE OH VALLEY BY
TONIGHT.

THE UPPER LEVEL PATTERN WILL THEN BECOME NEARLY ZONAL WITH A WEAK
SHORT WAVE  MOVE TO OUR NORTH BETWEEN 24 TO 48 HOURS. THIS TROUGH
WILL NOT HAVE MUCH MOISTURE TO WORK WITH AND ONLY A FEW HIGH CLOUDS
CAN BE EXPECTED.

A CUT OFF LOW WILL MOVE ACROSS THE EASTERN PACIFIC AND WILL BE ROUGHLY
LOCATED 250 MILES TO THE SOUTHWEST OF THE CA COAST BY 48 HOURS. THIS
WILL BE THE SYSTEM THAT WILL MOVE INTO THE AREA IN THE EXTENDED.

AT THE SURFACE...THE LOW WAS INITIALIZED OVER THE NORTHERN TX
PNAHANDLE AND HAD MOVE INTO CENTRAL OK BY 06Z. THIS LOW WILL MOVE
NORTHEASTWARD ACROSS SOUTHERN MO TODAY AND INTO SOUTH CENTRAL OH BY
TONIGHT.

AN ASSOCIATED COLD FRONT WILL DROP ACROSS THE NORTHWESTERN PART OF
THE STATE THIS MORNING. THE AVN HAS THE FRONT REACHING KLIT AROUND
18Z...BUT THIS MAT BE A BIT TOO FAST.  IT WILL EXIT THE STATE BY
EARLY EVENING.

A HIGH PRESSURE WILL BUILD BEHIND THE FRONT FOR SATURDAY WITH A
SECOND HIGH REINFORCING HIGH BUILDING IN FOR SUNDAY.

A DRY SLOT MOVES INTO NORTHWESTERN AR BY THE AFTERNOON AND THE
NORTHWESTERN 2/3RDS BY THIS EVENING.

...EXTENDED...
THE CLOSED LOW WILL WEAKEN AS IT MOVES INTO A RIDGE OVER THE ROCKIES
IN THE 48 TO 72 HOUR TIME FRAME. AS MENTIONED ABOVE...A REINFORCING
HIGH PRESSURE WILL BUILD IN FOR SUNDAY. I DIDN/T GET A CHANCE TO
LOOK AT THE MRF...SO I DIDN/T MAKE ANY CHANGES BEYOND THE FIRST DAY
OF THE EXTENDED.

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.LIT...LAKE WIND ADVISORY TODAY ARZ003>007-012>16-23>24.

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-181700-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LITTLE ROCK AR
515 AM CST FRI FEB 18 2000

...SEVERE THUNDERSTORM WATCH FOR MUCH OF ARKANSAS UNTIL 11 AM...

A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR MUCH OF ARKANSAS
UNTIL 11 AM THIS MORNING.

A WARM FRONT WAS LOCATED ACROSS THE CENTRAL PART OF THE STATE DURING
THE OVERNIGHT HOURS. THIS WARM FRONT WILL MOVE NORTHWARD ACROSS THE
STATE THIS MORNING. IT WILL ALLOW VERY WARM AND HUMID CONDITIONS TO
SPREAD ACROSS MUCH OF THE STATE.

AN AREA OF SHOWERS AND THUNDERSTORMS...WHICH DEVELOPED ACROSS EASTERN
OKLAHOMA DURING THE EARLY MORNING HOURS...WILL MOVE EASTWARD THIS
MORNING. SOME OF THESE THUNDERSTORM WILL LIKELY BECOME SEVERE.
LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE IN AND CLOSE TO THE
WATCH AREA. ALTHOUGH...DAMAGING WINDS IN EXCESS OF 58 MPH WILL BE
THE MAIN THREAT.

THE COLD FRONT WILL EXIT THE SOUTHEASTERN PART OF THE STATE BY
EARLY EVENING AND WILL TAKE MOST OF THE SHOWERS AND THUNDERSTORMS
WITH IT.

THOSE LIVING OR TRAVELING IN OR CLOSE TO THE WATCH AREA SHOULD KEEP
AN EYE ON THIS POTENTIALLY DANGEROUS SITUATION. STAY TUNED TO NOAA
WEATHER RADIO AND YOUR LOCAL MEDIA FOR LATER STATEMENTS AND
POSSIBLE WARNINGS.

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