Severe Thunderstorm Warning 50, NWS Lubbock, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
315 PM CDT THU MAY 23 2002

A MINOR H5 TROUGH WAS MOVING ACROSS THE CWFA EARLY THIS AFTERNOON.
SYNOPTIC SCALE VERTICAL MOTION AHEAD OF THIS TROUGH HELPED TO FORM
ELEVATED CONVECTION ACROSS THE CENTRAL AND NORTHEAST SECTIONS OF
THE CWFA LATE THIS MORNING AND EARLY THIS AFTERNOON. AT 18Z A
COLD FRONT WAS LOCATED OVER THE NORTHWEST COUNTIES OF THE CWFA. THE
COLD AIR MASS BEHIND THIS FRONT IS SHALLOW...AND SHOULD MIX OUT
ACROSS THE NORTHWEST COUNTIES LATE THIS AFTERNOON. A DRYLINE
EXTENDED ALONG I-27 AND WILL MIX EAST TO NEAR THE CAPROCK ESCARPMENT
LATER THIS AFTERNOON. ISOLATED THUNDERSTORMS MAY DEVELOP LATE THIS
AFTERNOON AND EVENING ALONG AND EAST OF THE SFC DRYLINE. THE
MESO-ETA FCST SND SHOWED ABOUT 2000 J/KG OF CAPE EAST OF THE SFC
DRYLINE. STEEP LAPSE RATES WERE NOTED ACROSS WEST TX AT 12Z. AT 18Z
TEXAS TECH-WEST TEXAS MESONET LAUNCHED A SOUNDING AT REESE
CENTER...WEST OF LBB. THE 18Z SOUNDING SHOWED ABOUT 1000 J/KG OF
CAPE WITH A CONVECTIVE TEMPERATURE OF 87 DEGREES. THE MOISTURE MAY
MIX OUT ONCE WE REACH CONVECTIVE TEMPERATURE IN LBB. THE BEST CHANCE
FOR ISOLATED THUNDERSTORMS WILL BE NORTHEAST OF LBB. THE LBB SND AT
500 MB SHOWED SOUTHWEST WINDS AT 55 KT. WITH SFC WINDS BACKED EAST
OF THE DRYLINE...VERTICAL WINDSHEAR PROFILES WILL BE SUFFICIENT FOR
ROTATING STORMS.  IF STORMS DO DEVELOP...THEY WILL BE HIGHER BASED
WITH THE PRIMARY THREAT BEING LARGE HAIL AND STRONG OUTFLOW WINDS.
FOR TONIGHT I WILL INCLUDE 20 POPS OVER THE CENTRAL AND SOUTHEAST
COUNTIES WITH 30 POPS OVER THE NORTHEAST COUNTIES.

AN H5 TROUGH OVER NORTHERN AZ WILL LIFT NORTHEAST ACROSS SOUTHEAST
CO AND SOUTHWEST KS TOMORROW AFTERNOON. SCATTERED THUNDERSTORMS WILL
DEVELOP ALONG THE COLD FRONT OVER OK AND WILL BACK BUILD TOWARDS THE
DRYLINE OVER THE NORTHEAST COUNTIES OF THE CWFA. ISOLATED
THUNDERSTORMS MAY DEVELOP FARTHER SOUTHWEST ALONG THE DRYLINE OVER
THE EASTERN AND CENTRAL COUNTIES IF THE CAPPING INVERSION WEAKENS.
LOW-LEVEL CAA ON THE BACK SIDE OF THE EXISTING H5 TROUGH WILL PUSH A
COLD FRONT SOUTHWARD ACROSS THE CWFA FRIDAY NIGHT. SATURDAY WILL BE
COOLER WITH EASTERLY SFC WINDS NORTH OF THE FRONTAL BOUNDARY.  AN H5
TROUGH WILL MOVE ON SHORE OVER SOUTHERN CA ON SATURDAY...WHICH WILL
CAUSE AN UPSTREAM H5 RIDGE TO BUILD OVER WEST TX. ISOLATED
THUNDERSTORMS MAY DEVELOP ACROSS THE CWFA SATURDAY AFTERNOON AND
EVENING AS DEEPER MOISTURE ADVECT WEST ACROSS THE CWFA NORTH OF THE
FRONTAL BOUNDARY. RAIN CHANCES WILL INCREASE SUNDAY AND MEMORIAL DAY
AS THE SOUTHERN CA H5 TROUGH MOVES EAST TOWARDS WEST TX.
THUNDERSTORMS WILL DEVELOP SUNDAY AFTERNOON OVER EASTERN NM ALONG
THE DRYLINE AND MOVE EAST ACROSS THE CWFA SUNDAY NIGHT. THIS LOOKS
TO BE OUR BEST CHANCE FOR RAIN.

ZONAL FLOW ALOFT WILL CONTINUE ACROSS WEST TX THROUGH NEXT THU. THE
MRF AMPLIFIES AN H5 RIDGE OVER THE WESTERN AND CENTRAL CONUS BY NEXT
THU. ISOLATED THUNDERSTORMS WILL BE POSSIBLE ALONG AND EAST OF THE
DRYLINE FROM TUE TO THU.

FRIONA       54/84/50/76  1222
TULIA        56/86/52/77  2222
BROWNFIELD   59/88/56/83  1223
LUBBOCK      58/88/55/81  2222
CHILDRESS    63/87/58/79  3332
ASPERMONT    66/88/63/83  2222

.LUB...NONE.

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