Hail and Damaging Wind in Texas, April 17, 2002

TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
445 PM CDT WED APR 17 2002

BAND OF MID/UPPER LEVEL SUB-TROPICAL MOISTURE WAS STREAMING
NORTHEAST OVER SOUTHERN PLAINS THIS AFTERNOON AS VARIOUS VORTICITY
LOBES ROTATED AROUND WESTERN U.S. TROUGH. ONE LOBE WAS MOVING OVER
SOUTHERN NV AND SOUTHERN UT AS OF MID-AFTERNOON AND IS LIKELY AIDING
THE SURFACE CYCLOGENESIS IN WY. MEANWHILE...SLOWLY RETREATING
DRYLINE WAS SHARPENING UP FROM NEAR KGAG SOUTHWEST TO NEAR TULIA.
ISOLD CONVECTION HAD INITIATED IN ZONE OF STRONGEST CONVERGENCE FROM
WESTERN OK INTO THE SOUTHEASTERN TX PNHDL. HOWEVER...STORMS ARE
STILL STRUGGLING TO MAINTAIN ORGANIZATION DUE TO STRONG MID/UPPER
LEVEL SHEAR AND STRENGTHENING CAP. THEREFORE...DECIDED TO MENTION
TSRA FOR EAST CENTRAL AND SOUTHEASTERN TX PNHDL...BUT NEXT SHIFT MAY
NEED TO INCLUDE NORTHEAST TX PNHDL AND EASTERN OK PNHDL IF DRYLINE
CONTINUES TO RETREAT.

SHORT RANGE MODELS ARE IN MODERATE AGREEMENT THROUGH NEXT 48 TO 60
HRS...MORE SO ALOFT AND LESS SO NEAR THE SURFACE. ETA IS MORE
AGGRESSIVE THAN AVN IN NEXT FRONT PUSHING SOUTH INTO THE PNHDLS BY
FRIDAY MORNING. QUESTION STILL REMAINS ABOUT HOW FAR IT WILL GO. AS
TIME MOVES FURTHER INTO SPRING...COLD FRONTS HAVE A HARD TIME
BARRELING THROUGH THE AREA UNLESS THEY ARE AIDED BY A VERY COLD
AIRMASS AND/OR HAVE A MODERATE AMOUNT OF CONVECTION ASSOCIATED WITH
IT. SHORT RANGE AND MEDIUM RANGE MODELS INDICATING THAT UPPER LEVEL
TROUGH SHOULD STAY OUT WEST AND BECOME POSITIVELY TILTED BY THE END
OF THE WEEK THEN BEGIN TO SHEAR OUT DURING THE WEEKEND. THEREFORE...
DECIDED TO EXPAND TSRA POPS TEMPORALLY ACROSS THE AREA BACK INTO
FRIDAY AFTN AND INTO SUNDAY.

LOWERING HEIGHTS AND NEAR ZONAL FLOW ALOFT WILL RETURN EARLY NEXT
WEEK ALONG WITH DEVELOPING TROUGH. POSSIBLE DRYLINE REDEVELOPMENT BY
THE MIDDLE OF NEXT WEEK. FOR NOW WILL CONTINUE WITH SLIGHTLY COOLER
TEMPERATURES AND PARTLY CLOUDY SKIES.

FINAL NUMBERS...
AMA UE 054/084 048/074 045 00022
DHT UE 052/083 046/070 041 00022

.AMA...
TX...NONE.
OK...NONE.

JH

OKZ001>003-TXZ001>020-172200-

TEXAS/OKLAHOMA PANHANDLES THUNDERSTORM OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
113 PM CDT WED APR 17 2002

A DRYLINE...WHICH IS A BOUNDARY BETWEEN MOIST AND DRY AIR...HAS
INCHED WESTWARD BACK INTO THE EXTREME SOUTHEAST TEXAS PANHANDLE.
THE AIRMASS EAST OF THE DRYLINE IN COLLINGSWORTH AND WHEELER
COUNTIES WILL BE UNSTABLE AND WITH THE FOCUSING ACTION OF THE
DRYLINE IN THE AREA...A FEW STORMS WILL DEVELOP.  THE THREAT AREA
WILL BE PRIMARILY IN WHEELER AND COLLINGSWORTH COUNTIES THROUGH LATE
THIS AFTERNOON.  LARGE HAIL AND STRONG WINDS WILL BE THE PRIMARY
THREAT. THE REST OF THE TEXAS AND OKLAHOMA PANHANDLES WILL HAVE A
VERY DRY AIRMASS IN PLACE WHICH SHOULD INHIBIT STORM DEVELOPMENT.

SPOTTERS AND EMERGENCY MANAGEMENT OFFICIALS IN THE FAR SOUTHEAST
TEXAS PANHANDLE SHOULD REMAIN ALERT FOR POSSIBLE ACTIVATION.

THE NEXT REGULARLY SCHEDULED THUNDERSTORM OUTLOOK WILL BE ISSUED
AROUND 6 AM CDT THURSDAY.

SP