Severe Thunderstorm Warning 124, NWS Lubbock, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
325 PM CDT THU MAY 31 2007

.SHORT TERM...
ATTENTION CONTINUES TO BE FOCUSED ON A POTENTIALLY TWO PRONGED
SEVERE WEATHER THREAT. THE FIRST AREA OF CONCERN IS IN REFERENCE TO
THE INCREASING CONVECTIVE TRENDS OVER THE HIGHER TERRAIN OF EASTERN
NEW MEXICO AND WEST TEXAS. CURRENT ANALYSIS INDICATES STRONG
INSTABILITY FROM THE NEW MEXICO PLAINS EASTWARD OVER THE EXTREME
SOUTHERN FA...JUST SOUTH OF AN APPARENT DIFFUSE SURFACE BOUNDARY.
ALTHOUGH A PRONOUNCED WIND SHIFT DOES NOT EXIST WITH THIS
BOUNDARY...IT IS EVIDENT AS A STRONG INSTABILITY GRADIENT AND IS
SEEN IN THE CU FIELD/VIS IMAGERY. INFLUENCES OF DIFFERENTIAL HEATING
LIKELY EXIST ALONG THE BOUNDARY SOUTH OF TODAY/S PERSISTENT CLOUD
COVER OVER THE SOUTH PLAINS. WEAK FORCING/ASCENT WILL OVERSPREAD
AREAS TO OUR SOUTHWEST BY EARLY EVENING...AS SEEN IN CURRENT MID
CLOUD/VAPOR ENHANCEMENT. THUS IT IS PLAUSIBLE THAT CONVECTION
INITIATING OVER NEW MEXICO WILL SPREAD EASTWARD TOWARD THE WESTERN
SOUTH PLAINS...WHERE STRONG INSTABILITY AND INCREASING SHEAR WILL
CO-EXIST...ESPECIALLY AROUND/AFTER SUNSET. A FEW SUPERCELLS SEEM
POSSIBLE GIVEN THE INCREASING WIND FIELDS...AND EXPECT SEVERE
THREATS WILL INCLUDE VERY LARGE HAIL...AND PERHAPS A FEW BRIEF
TORNADOES.

A SECONDARY AND PERHAPS SIGNIFICANT SEVERE THREAT IS EXPECTED TO
MATERIALIZE LATER IN THE EVENING/AFTER MIDNIGHT WHEN A MATURE MCS
WILL PROPAGATE SOUTHEASTWARD THROUGH THE PANHANDLE/WESTERN OKLAHOMA
IN PROXIMITY TO THE NORTHEASTERN ZONES. CONVECTIVE MODE WILL LIKELY
FAVOR DAMAGING WINDS WITH THIS ACTIVITY.

HAVE MADE SOME MODIFICATIONS TO THE SENSIBLE WEATHER GRIDS FOR
FRIDAY AFTERNOON AS MODELS INDICATE A POSSIBLE TRIPLE POINT NEAR THE
NORTHERN ZONES. STORM CHANCES WILL AGAIN BE WITH US...WITH A
CONDITIONAL RISK OF SEVERE WEATHER.

.LONG TERM...
MODELS IN GOOD AGREEMENT THROUGH AROUND WEDNESDAY WITH UPPER LOW
MEANDERING AROUND THE NORTHERN PLAINS FRIDAY TO SLOWLY MOVE ACROSS
THE UPPER MID WEST OVER THE WEEKEND...AND TOWARD THE GREAT LAKES
REGION BY THE BEGINNING OF THE NEXT WORKWEEK. UPPER RIDGE TO BUILD
OVER THE WESTERN CONUS...MOVING INTO THE CONTINENTAL DIVIDE ON
MONDAY...THEN BEGINNING TO FLATTEN AS IT MOVES INTO THE LEE OF THE
ROCKIES AND A STRONG SHORTWAVE MOVES INTO THE PACIFIC NORTHWEST.
MODELS DIFFER ON HANDLING OF SHORTWAVE OVER THE PACIFIC NORTHWEST
WITH ECMWF AND CANADIAN DIGGING A SLIGHTLY NEGATIVE TILTED TROFF
INTO THE CENTRAL ROCKIES BY LATE WEDNESDAY. GFS AND NOGAPS HAVE
SHORTWAVE MOVING ALONG THE CANADIAN BORDER WITH A NEAR ZONAL
FLOW ACROSS THE REGION WEDNESDAY AND THURSDAY.

COLD FRONT EXPECTED TO MOVE INTO THE PANHANDLE BY LATE FRIDAY
AFTERNOON WITH DRY LINE OVER THE WESTERN SOUTH PLAINS AND TRIPLE
POINT VICINITY OF CLOVIS NEW MEXICO. THESE FEATURES TO ACT AS
FOCUS FOR THUNDERSTORM DEVELOPMENT WITH POSSIBLE MCS MOVING
SOUTHEAST ACROSS THE REGION DURING THE NIGHT. THERE MAY STILL BE
ONGOING PRECIPITATION OVER MY SOUTHEAST ZONES SATURDAY MORNING
FRONT TO REMAIN QUASI-STATIONARY OVER THE FORECAST AREA ON
SATURDAY BEFORE SLIDING SOUTH INTO THE PERMIAN BASIN ON SUNDAY.
THUS CONTINUED CHANCE POPS FOR SATURDAY AND SATURDAY NIGHT AND
WITH NORTHWEST FLOW ALOFT AGAIN FOR SUNDAY AND MONDAY AFTERNOONS
AND NIGHTS AS GFS INDICATES THUNDERSTORMS DEVELOPING IN HIGHER
TERRAIN OF NEW MEXICO MOVING SOUTHEAST ACROSS THE REGION. LEE
SIDE TROFF EXPECTED TO DEVELOP NEAR THE TEXAS NEW MEXICO BORDER
NEXT TUESDAY INTO THURSDAY WITH TEMPERATURES CLIMBING TO ABOVE
NORMAL.

&&

.AVIATION...
MODELS CONTINUE TO INDICATE THAT THE CURRENT CLEAR SKIES AT KLBB
WILL GIVE WAY TO INCREASING LOW CLOUDS OVERNIGHT. SOME UNCERTAINTY
REMAINS WITH THE TIMING OF SAID ONSET...BUT SCATTERED CUMULUS CLOUDS
WILL LIKELY OVERSPREAD THE TERMINAL LATE THIS AFTERNOON...WITH A
TREND TOWARD LOWER CEILINGS AFTER 03Z. BEST POTENTIAL FOR MVFR/IFR
CIGS WILL BE DURING THE 10Z TO 14Z TIMEFRAME.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        59  85  58  82  56 /  40  40  40  20  30
TULIA         58  83  58  80  59 /  50  40  50  20  30
PLAINVIEW     61  84  60  81  61 /  40  20  50  20  30
LEVELLAND     63  86  61  82  61 /  40  20  30  20  20
LUBBOCK       66  86  62  82  63 /  40  20  40  20  20
BROWNFIELD    65  86  63  83  62 /  40  20  30  20  20
CHILDRESS     67  84  65  81  64 /  60  30  50  20  30
SPUR          66  86  64  82  64 /  40  20  50  20  30
ASPERMONT     69  87  65  84  66 /  50  20  50  30  30

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

20/08/20

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
1252 PM CDT THU MAY 31 2007

TXZ021>044-011800-
PARMER-CASTRO-SWISHER-BRISCOE-HALL-CHILDRESS-BAILEY-LAMB-HALE-
FLOYD-MOTLEY-COTTLE-COCHRAN-HOCKLEY-LUBBOCK-CROSBY-DICKENS-KING-
YOAKUM-TERRY-LYNN-GARZA-KENT-STONEWALL-
1252 PM CDT THU MAY 31 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE EXTREME SOUTHERN TEXAS
PANHANDLE...SOUTH PLAINS AND ROLLING PLAINS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

CONVECTIVE

A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS FROM LATE THIS
AFTERNOON THROUGH TONIGHT OVER THE SOUTHERN PANHANDLE...SOUTH
PLAINS AND ROLLING PLAINS. SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP LATE THIS AFTERNOON ACROSS THE HIGHER TERRAIN OF NEW
MEXICO AND MOVE THROUGH THE AREA DURING THE EVENING AND OVERNIGHT
HOURS. ADDITIONALLY...CONVERGENCE ALONG THE EDGE OF THE CAPROCK
AND A RETREATING ALBEIT SUBTLE FRONT MAY BE ENOUGH TO INITIATE
THUNDERSTORMS ACROSS THE SOUTH PLAINS AND ROLLING PLAINS BY LATE
AFTERNOON...ALTHOUGH A STRONG CAP IN PLACE MAY LIMIT THIS DEVELOPMENT.

MODERATE LOW TO MID LEVEL WIND SHEAR COMBINED WITH A VERY MOIST AND
UNSTABLE AIRMASS WILL CREATE A FAVORABLE ENVIRONMENT FOR SUPERCELL
THUNDERSTORMS. THE PRIMARY THREATS WILL BE LARGE HAIL AND DAMAGING
WINDS WITH ANY DISCRETE CELLS...THOUGH AN ISOLATE TORNADO IS ALSO
POSSIBLE. THEN...THE THREAT WILL TRANSITION TOWARD DAMAGING WINDS
OVERNIGHT AS THE STORMS MERGE INTO A LINE OR COMPLEX.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SCATTERED THUNDERSTORMS ARE AGAIN EXPECTED TO DEVELOP LATE FRIDAY
AFTERNOON AND EVENING ACROSS THE SOUTHERN PANHANDLE AS ANOTHER
COLD FRONT MOVES INTO THIS AREA. OTHER STORMS MAY DEVELOP ACROSS
EASTERN NEW MEXICO DURING THE AFTERNOON AND MOVE TOWARD THE AREA
OVERNIGHT. SUFFICIENT WIND SHEAR AND INSTABILITY MAY RESULT IN
SOME STORMS BECOMING SEVERE WITH LARGE HAIL THE PRIMARY THREAT. IF
THE STORMS DEVELOP INTO A LARGE COMPLEX DURING THE
EVENING...DAMAGING WINDS MAY ALSO OCCUR.

CLUSTERS OF THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGHER
TERRAIN OF NEW MEXICO LATE SATURDAY AND AGAIN LATE SUNDAY. WITH
NORTHWEST FLOW ALOFT...THE STORMS WOULD MOVE INTO THE AREA MAINLY
DURING THE EVENING AND OVERNIGHT HOURS. SOME STORMS MAY BE SEVERE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED FROM LATE AFTERNOON THROUGH THE
EVENING AND OVERNIGHT HOURS.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
758 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0756 PM     HAIL             3 W PETERSBURG          33.87N 101.65W
05/31/2007  E1.75 INCH       HALE               TX   LAW ENFORCEMENT

&&

JDV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
809 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0809 PM     HAIL             PETERSBURG              33.87N 101.60W
05/31/2007  E1.75 INCH       HALE               TX   PUBLIC

            RELAYED BY BROADCAST MEDIA

&&

JDV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
817 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0815 PM     HAIL             1 S COTTON CENTER       33.98N 101.99W
05/31/2007  E0.75 INCH       HALE               TX   SKYWARN SPOTTER

            PENNY SIZE HAIL ALONG 179 SOUTH OF COTTON CENTER

&&

JDV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
820 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0818 PM     TORNADO          2 S PETERSBURG          33.84N 101.60W
05/31/2007                   HALE               TX   FIRE DEPT/RESCUE

            RALLS FD REPORTS TORNADO JUST SOUTH OF PETERSBURG

&&

JDV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
824 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0818 PM     HAIL             12 SW FLOYDADA          33.86N 101.48W
05/31/2007  E2.50 INCH       FLOYD              TX   EMERGENCY MNGR

&&

JDV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
825 PM CDT THU MAY 31 2007

..TIME..    ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE..    ....MAG....     ..COUNTY LOCATION.. ST.. ...SOURCE....
            ..REMARKS..

0822 PM     HAIL             PETERSBURG              33.87N 101.60W
05/31/2007  E1.75 INCH       HALE               TX   BROADCAST MEDIA

            HAIL IS COVERING THE GROUND IN PETERSBURG

&&

JDV