Severe Thunderstorm Warning 313, NWS Little Rock, AR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
345 PM CDT WED JUN 14 2000

REGIONAL RADAR LOOPS INDICATE AN AREA OF SHOWERS AND THUNDERSTORMS
ALONG AND AHEAD OF THE FRONT FROM THE GREAT LAKES THROUGH
NORTHWESTERN AR AND INTO NORTH CENTRAL TX. ACROSS AR...THESE ARE
MAINLY MODERATE TO LOCALIZED HEAVY RAINERS...BUT ISOLATED SEVERE
THUNDERSTORMS MAY BE SEEN INTO THE EVENING WITH DEWPOINTS IN THE 70S
AND LAPS LI/S DOWN TO -6. IN THE UPPER LEVELS...THERE WAS A CLOSED
LOW...CENTERED OVER THE SD/MN BORDER WITH A TROUGH ACROSS THE
CENTRAL PLAINS. THE CLOSED LOW CAN BE CLEARLY SEEN ONN THE WV
IMAGERY. THERE IS ALSO TWO RIDGES WITH ONE ACROSS FL AND THE WESTERN
ATLANTIC AND THE SECOND ACROSS THE EASTERN PACIFIC AND INTO THE
DESERT SOITHWEST.

OVERALL...THE MODELS INITIALIZED FAIRLY WELL. BUT...APPARENTLY WERE
SLIGHTLY TO WEAK WITH THE CLOSED LOW OVER THE NORTHERN PLAINS. THE
NGM ALSO DOESN/T HAVE A STRONG ENOUGH SYSTEM IN THE GULF AND
THEREFORE...I HAVE MAINLY BASED THE FORECAST ON THE AVN AND ETA.
THROUGH THE PERIOD...THE LONG WAVE TROUGH ACROSS THE CENTRAL US
EXPANDS ACROSS MUCH OF THE COUNTRY. IT FORCES THE HIGHS TO RETREAT
INTO THE FURTHER INTO THE WESTERN ATLANTIC AND EASTERN PACIFIC.

A STRING OF SHORT WAVES WILL MOVE PARALLEL TO THE FRONT OVER THE
NEXT 24 HOURS WITH THE SHORT WAVE CURRENTLY OVER THE CENTRAL GULF
MOVING INTO THE SOUTHEAST OVER THE NEXT COUPLE OF DAYS. A SECOND
SHORT WAVE IN THE GULF WILL APPROACH THE SOUTHERN LA COAST BY THE
END OF THE PERIOD.

AT THE SURFACE...THE MODELS ALSO HAVE INITIALIZED DECENTLY WITH A
LOW OVER NORTHERN MN AND AN ASSOCIATED COLD FRONT...EXTENDING
THROUGH IA...MO...SOUTHEASTERN KS AND OK AND FINALLY TO A SECOND LOW
OVER WEST TX.

BY 24 HOURS...THE NORTHERN PART OF THE COLD FRONT WILL MOVE INTO THE
GREAT LAKES WITH THE SOUTHERN PART OF THE FRONT DISSIPATING...AS IR
MOVES ACROSS THE STATE.

A SECONDARY COLD FRONT WILL PUSH OUT OF CANADA AND INTO THE UPPER MS
VALLEY AND INTO THE NORTHERN PLAINS BY 48 HOURS.

IN TERMS OF PRECIPITATION...THE AREA OF SHOWERS AND THUNDERSTORMS
WILL BE EXITING THE NORTHWESTERN PART OF MY CWFA BY THIS EVENING AND
I HAVE ONLY KEPT A SLIGHT TO LOW CHANCE POPS THERE. ELESEWHERE...I
HAVE MENTIONED 50 TO 60% CHANCE THIS EVENING DECREASING TO 30
PERCENT CHANCE AFTER MIDNIGHT. I HAVE ALSO MENTIONED A SLIGHT CHANCE
ACROSS THE SOUTHEASTERN HALF OF MY CWFA FOR THURSDAY MORNING. THE
CHANCE WILL ONCE AGAIN BEGIN TO INCREASE...AS THE COLD FRONT
APPROACHES FRIDAY AFTERNOON AND EVENING. OVERALL...THIS IS A
COMPOSITE BETWEEN THE FAN AND FEC MOS.

IN TERMS OF TEMPERATURES...I WENT FAIRLY CLOSE TO THE FAN MOS
NUMBERS. ALTHOUGH THE FWC AND MAV NUMBERS ARE CLOSE.

...EXTENDED...
THE ECMWF IS TENDING CLOSER TO A MORE ZONAL FLOW INTO NEXT WEEK.
WHILE THE MRF REMAINS MORE AMPLIFIED. I THINK THE MRF IS CLOSER TO
THE REAL PICTURE. THE SECOND COLD FRONT WILL MOVE INTO THE STATE
LATE FRIDAY NIGHT AND INTO SATURDAY...BEFORE SLOWING DOWN AND
DISSIPATING ACROSS THE STATE OVER THE WEEKEND. THERE WILL BE ENOUGH
MOISTURE AROUND INTO ERALY NEXT WEEK TO KEEP THE THREAT OF SCATTERED
SHOWERS OR THUNDERSTORMS.

(49)

.LIT...NONE.