Severe Thunderstorm Warning 49, NWS Shreveport, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
220 PM CST SAT MAR 18 2000

WILL HAVE HANDS FULL TONIGHT AS COMPLEX LOW OUT OF SOUTHERN ROCKIES
CREATING SEVERAL AREAS OF CONVECTION ACROSS SOUTHERN PLAINS AND
GULF COAST. DEVELOPING LINE OF STORMS IN EAST TX IN VERY WARM AND
MOIST AIR. MORE SUN OCCURRED TODAY THAN EXPECTED AND LFK ALREADY
REACHED 80 DEGREES WITH DEWPOINT OF 64. UPDRAFT POTENTIAL ALONG
WITH LOWERING WET BULB ZEROES INCREASE THREAT OF HAIL...WITH
DOPPLER ALREADY DOING HAIL ALERTS. GENERAL MID LEVEL FLOW FAVORABLE
FOR MESO DEVELOPMENT. SOME LOW LEVEL BACKING SEEN ON FORT POLK VAD
PROFILE...BUT NOT INDICATING FURTHER NORTH AT SHV. EXPECT GREATEST
SEVERE THREAT TO THE SOUTH. ETA/AVN INDICATE LESS INSTABILITY
OVERNIGHT WITH MID LEVEL COLD AIR ADVECTION UNTIL AFTER MIDNIGHT.
THUS...SEVERE THREAT SHOULD END BEHIND THIS SQUALL LINE. HOWEVER...
THE ONSET OF STRONG HEIGHT FALLS ALONG WITH CONTINUED UPPER LEVEL
DIVERGENCE AND STRONG MOISTURE CONVERGENCE INDICATE HEAVY RAIN MCS
TO SET UP FOR MUCH OF THE NIGHT...ESPECIALLY EAST PORTIONS OF AREA.
LEAVE IN A CHANCE OF RAIN INTO SUNDAY WITH DEEPER MOISTURE REMAINING
MOSTLY NORTH SECTIONS OF AREA. HIGH PRESSURE TO PREVAIL ON MONDAY...
MOSTLY SUNNY SKIES AND A GOOD WARMUP AS MASSIVE CLOSED LOW DEVELOPS
NEAR FOUR CORNER REGION AND SURFACE LOW TO ITS EAST BRING RETURN
FLOW EAST TX BY LATE MONDAY.

AT LEAST MODEL TEMPS IN GOOD AGREEMENT AS ONLY DIFFERENCE LIES IN
4TH PERIOD WHERE I WILL SPLIT THE DIFFERENCE.

SHV 52/59/39/68  8400     TYR 49/58/41/70  6200
MLU 55/60/41/65  8710     LFK 54/63/39/72  7200
TXK 51/57/40/65  7510

VII

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-181740-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
1035 AM CST SAT MAR 18 2000

AN UPPER LEVEL TROUGH WAS LOCATED OVER THE SOUTHERN ROCKIES THIS
MORNING. AN AREA OF LOW PRESSURE WAS ALSO DEEPENING OVER NORTH
TEXAS...ALONG A DEVELOPING COLD FRONT IN WEST TEXAS. THE AIRMASS
WILL BECOME UNSTABLE THIS AFTERNOON AS WARM AIR AND MOISTURE IS
BROUGHT NORTH FROM THE GULF OF MEXICO. AS BREAKS IN THE CLOUDS ALLOW
TEMPERATURES TO WARM TO NEAR 70 EARLY THIS AFTERNOON...AND AN OLD
FRONTAL BOUNDARY ALONG THE COAST MOVES NORTH AS A WARM
FRONT...SCATTERED SHOWERS AND THUNDERSTORMS SHOULD DEVELOP ACROSS
EAST TEXAS AND NORTH CENTRAL LOUISIANA. A FEW STORMS COULD BECOME
SEVERE ACROSS EAST TEXAS AND LOUISIANA THIS AFTERNOON AND EVENING.
COLD AIR ALOFT AND LIFTING OF THE ATMOSPHERE NEAR THE UPPER LEVEL
SYSTEM WILL INCREASE SHOWER AND THUNDERSTORM ACTIVITY ALONG THE RED
RIVER VALLEY REGION OF NORTHEAST TEXAS...SOUTHEAST OKLAHOMA...AND
SOUTHWEST ARKANSAS LATE THIS AFTERNOON AND TONIGHT WITH A FEW
THUNDERSTORMS BECOMING SEVERE.

THE ACTIVATION OF SEVERE THUNDERSTORM SPOTTERS...SKYWARN
NETWORKS...HAM RADIO OPERATORS...AND EMERGENCY MANAGEMENT PERSONNEL
MAY BE REQUIRED THIS AFTERNOON THROUGH TONIGHT.