FXUS64 KSHV 082136
AFDSHV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
336 PM CST TUE DEC 8 2009
.DISCUSSION...
WARM FRONT HAS SURGED NORTHWARD OF INTERSTATE 20 ACROSS MOST OF
NORTHERN LA. TWO CONVECTIVE LINES HAVE FORMED...NEAR THE SFC WARM
FRONT BOUNDARY... AND FURTHER SE IN WARM SECTOR. INSTABILITY HAS
BEEN LIMITING FACTOR...AS DYNAMICS IN LOWER AND UPPER LVLS BOTH
FAVORABLE FOR SVR ROTATING STORMS. A TORNADO WATCH IN EFFECT FOR
NORTHCENTRAL LA UNTIL 9 PM...COULD BE PREMATURELY ENDED IF THIS
ACTIVITY DOES NOT INCREASE...AND ORE MOVES EAST OF AREA BY EARLY
THIS EVE. STRONG COLD FRONT SEEN ON OBS WELL BACK IN WEST TX...
BUT MOVING QUICKLY AS SEEN ON POSTFRONTAL WIND SHIFTS. LIMITED
TIME FOR FROPA BEFORE DAYBREAK MAKING FOR TRICKY OVERNIGHT LOW
FCST.
HIGH PRESSURE WILL PREVAIL WEDNESDAY INTO THURSDAY. MODEL HINT AT
SOME UPPER LVL CLOUDINESS GENERATED IN STRONG ZONAL FLOW ALOFT.
SOME ISENTROPIC LIFT NOTED FRIDAY AND FRIDAY EVENING...MOSTLY JUST
LIGHT RAIN EXPECTED AS NO CHANCE FOR GULF TO OPEN UP. WEAK SFC LOW
DEVELOPMENT NEAR GULF COULD ENHANCE PCPN TO THE SOUTH.
BY LATER IN THE WEEKEND...A COLD FRONT WILL BEGIN TO MOVE SLOWLY
SOUTH THRU THE CENTRAL PLAINS. UNCERTAIN ON TIMING OF THIS FRONT
AS DEEP SW FLOW WILL REMAIN ACROSS MUCH OF THE PLAINS AND ARKLATEX./VII/
&&
.AVIATION...
POOR FLIGHT CONDITIONS WILL PERSIST THROUGH THE NEXT SEVERAL HOURS
FOR THE FOUR STATE REGION. SHOWERS AND THUNDERSTORMS ARE BEING
OBSERVED OVER THE SOUTHEASTERN HALF OF THE REGION THIS AFTERNOON.
THIS ACTIVITY WILL CONTINUE TO DRIFT EAST THIS AFTERNOON...LEAVING
THE EASTERN FRINGES OF THE FORECAST AREA BY 3Z...IF NOT AN HOUR OR
SO SOONER. CIGS OVER THIS AREA ARE GENERALLY SITTING BELOW 3 KFT.
HOWEVER...A FEW BREAKS IN THE CLOUDS COULD BE POSSIBLE. ON THE
NORTHWESTERN HALF OF THE REGION...CIGS AROUND OR BELOW 1 KFT AND
SOME PERIODS OF FOG WILL CONTINUE FOR THE NEXT FEW HOURS. ONCE ALL
OF THE RAIN MOVES OUT...EASTERN SITES WILL SEE THIS AS WELL.
PERIODS OF DRIZZLE WILL BE POSSIBLE AFTER ALL THE RAIN HAS PASSED
THROUGH AS WELL. EXPECT DRIZZLE TO END AND CLOUDS TO
LIFT...ALLOWING FOR IMPROVING CONDITIONS FROM WEST TO EAST BEGINNING
AROUND 01-04Z IN THE WEST...IMPROVING OVER THE EAST AROUND MIDNIGHT.
OTHERWISE...WINDS WILL CONTINUE OUT OF THE SOUTH BETWEEN 5-10 KTS
THIS AFTERNOON AND EVENING...WITH OCCASIONAL HIGHER GUSTS. LATE
THIS EVENING INTO THE EARLY OVERNIGHT HOURS...THE WINDS WILL SHIFT
AROUND TO THE NORTHWEST AND BRING GUSTY CONDITIONS FOR THE OVERNIGHT
HOURS AND INTO WEDNESDAY MORNING. WINDS ARE EXPECTED TO SLACK BACK
TO 5-10 KTS TOWARD THE END OF THE 00Z FORECAST PACKAGE. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 38 48 29 48 35 / 10 10 0 10 20
MLU 43 49 29 48 34 / 40 10 0 10 20
DEQ 30 41 22 47 33 / 10 10 0 0 20
TXK 34 44 24 46 34 / 10 10 0 0 20
ELD 37 45 25 46 34 / 40 10 0 10 20
TYR 34 44 29 49 39 / 10 10 0 0 20
GGG 35 45 29 49 37 / 10 10 0 10 20
LFK 41 55 30 51 40 / 20 10 0 10 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$