Hail and Damaging Winds in Texas, April 18, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
330 PM CDT MON APR 18 2005

.SHORT TERM...
THE DRYLINE HAS SET UP TODAY NEAR THE NEW MEXICO-TEXAS STATE LINE...
OR WELL WEST OF ALL EARLIER MODEL DEPICTIONS. LATEST RUC MODEL HAS
ATTEMPTED TO RESPOND BY BREAKING OUT CONVECTION A GOOD 90 MILES OR
SO WEST OF THE 12Z RUNS. WE HAD ALREADY ANTICIPATED THE POOR MODEL
DEPICTIONS OF SURFACE DEWPOINTS...SO NEEDED ONLY TO BACK THUNDERSTORM
CHANCES A BIT FURTHER WEST THAN THE PREVIOUS FORECAST. STRONG CAPES
AND LOW SHEAR POINT TOWARDS MAINLY A HAIL THREAT THIS AFTERNOON AND
EARLY EVENING...AND THE SPC HAS ISSUED SEVERE THUNDERSTORM WATCH FOR
OUR NORTHERN ZONES EXCEPT THE NORTHERN TWO COUNTIES IN THE ROLLING
PLAINS UNTIL 10 PM. EXPECT ACTIVITY TO EDGE SLOWLY EASTWARD EARLY
THIS EVENING...PERHAPS INTENSIFYING NEAR DARK AS LOW LEVEL JET
STARTS TO DEVELOP. WE MAY HAVE ACTIVITY SPREAD TOO FAR EAST FOR THIS
EVENING...BUT ENOUGH SOUTHWEST FLOW ALOFT STILL WARRANTS MENTION OF
THUNDERSTORMS ALL ZONES TONIGHT.

A BIT MORE WESTERLY COMPONENT EXPECTED ON TUESDAY...THOUGH CHOSE TO
FAVOR THE MOST WESTERLY DEPICTION OF THE DRYLINE AND EVEN THEN WENT
A BIT FURTHER WEST. PREVIOUS GRIDS INDICATED THUNDERSTORM CHANCES TO
MATCH THIS EFFORT.  MINOR CHANGES OTHERWISE.  MCQUEEN

.LONG TERM...
DRYLINE WILL CONTINUE TO BE THE FOCUS FEATURE WEDNESDAY AND
THURSDAY. LARGE UPPER LEVEL STORM SYSTEM OVER THE WEST COAST
STATES IS PROGGED BY NAM AND GFS TO MOVE SLOWLY SOUTH AND EAST
THROUGH THURSDAY. MID TO UPPER LEVEL FLOW COULD INCREASE ACROSS
THE FOUR CORNERS REGION AND TEXAS SOUTH PLAINS. THE INCREASED
UPPER LEVEL WINDS COULD HELP THE DRYLINE MIX FURTHER EAST BOTH
WEDNESDAY AND THURSDAY. BEST FOCUS FOR THUNDERSTORMS WILL BE ALONG
AND EAST OF THE DRYLINE WITH BETTER MOISTURE IN PLACE. KEPT POP
CONFIGURATION MUCH THE SAME BOTH DAYS WITH THE FOCUS ON THE
ROLLING PLAINS.

CENTRAL PLAINS FRONT STILL PROGGED TO SLOWLY PUSH SOUTH ON
THURSDAY...NOSING INTO THE SOUTH PLAINS THURSDAY EVENING OR EARLY
FRIDAY MORNING. DYNAMICS ALONG THE BOUNDARY LOOK WEAK...BUT CANNOT
RULE OUT A SHOWER OR THUNDERSTORM IF LOW LEVEL MOISTURE REMAINS IN
PLACE.

UPSLOPE FLOW AND INCREASED MID AND HIGH CLOUDS POSSIBLE FRIDAY
THROUGH SUNDAY. GFS HAS BEEN PERSISTENT IN KEEPING DECENT UPSLOPE
COMPONENT INTO SATURDAY AND SUNDAY WITH ABUNDANT MOISTURE IN
PLACE. COULD ALSO BE A FEW SHOWERS. KEPT LOW ORDER POPS IN PLACE
ACROSS THE REGION AS UNCERTAINTY REMAINS.

UPPER LOW COULD APPROACH FOUR CORNERS REGION BY DAY 7. GFS REMAINS
QUITE BULLISH ON ITS QPF FIELDS WITH LOW LEVEL MOISTURE SURGING
NORTH. WILL HOLD OFF ON HIGHER POPS FOR NOW.

VERY LITTLE CHANGES MADE AS FORECAST IS IN GOOD SHAPE.

KW

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        48  82  47  79 /  10  10  10  10
TULIA         53  82  52  83 /  30  20  20  30
PLAINVIEW     54  82  53  84 /  30  20  20  30
LEVELLAND     53  84  51  85 /  20  10  10  10
LUBBOCK       55  84  54  83 /  30  20  20  20
BROWNFIELD    55  85  53  84 /  20  10  10  10
CHILDRESS     58  83  57  83 /  40  30  30  30
SPUR          59  83  58  82 /  30  30  30  30
ASPERMONT     61  81  59  83 /  30  20  30  30

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
TX...NONE.

&&

05/17

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
1130 AM CDT MON APR 18 2005

TXZ021>044-191630-
BAILEY-BRISCOE-CASTRO-CHILDRESS-COCHRAN-COTTLE-CROSBY-DICKENS-FLOYD-
GARZA-HALE-HALL-HOCKLEY-KENT-KING-LAMB-LUBBOCK-LYNN-MOTLEY-PARMER-
STONEWALL-SWISHER-TERRY-YOAKUM-
1130 AM CDT MON APR 18 2005

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

.DAY ONE...

CONVECTIVE

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE
EXTREME SOUTHERN PANHANDLE...SOUTH PLAINS AND ROLLING PLAINS LATE
THIS AFTERNOON INTO THE EVENING. THIS AREA IS GENERALLY ALONG AND
EAST OF A DIMMITT TO BROWNFIELD LINE.

THE DRYLINE IS EXPECTED TO SLOWLY MIX EASTWARD INTO THE CENTRAL
SOUTH PLAINS THROUGH THE AFTERNOON AS THE LOW LEVEL CLOUD COVER
ERODES. CONVERGENCE ALONG THE DRYLINE MAY BE ENOUGH TO INITIATE A
FEW THUNDERSTORMS. MODERATE INSTABILITY IN THE MIDDLE LEVELS OF THE
ATMOSPHERE AND A PIECE OF JET ENERGY PASSING THROUGH THE
SUBTROPICAL JET TO OUR SOUTH MAY HELP TO STRENGTHEN THE
THUNDERSTORMS THAT DEVELOP TO SEVERE LEVELS. THE STRONGEST STORMS
WILL HAVE THE ABILITY TO ROTATE BUT CLOUD BASES WILL BE HIGH ENOUGH
TO LIMIT THE SEVERE THREAT TO LARGE HAIL AND DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...

SEVERE THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON AND EVENING
ACROSS THE EASTERN SOUTH PLAINS INTO THE ROLLING PLAINS...AS DAYTIME
HEATING AND LOW LEVEL MOISTURE INTERACT WITH MODERATE INSTABILITY
ALONG THE DRYLINE...WHICH IS EXPECTED TO ADVANCE EASTWARD INTO THE
ROLLING PLAINS AND SOUTHEASTERN PANHANDLE BY LATE EVENING.

THE DRYLINE WILL ADVANCE FARTHER EAST ON WEDNESDAY...WITH THE THREAT
OF STRONG TO SEVERE THUNDERSTORMS MAINLY LIMITED TO AREAS EAST OF
THE CAPROCK FROM THE SOUTHEASTERN PANHANDLE INTO THE ROLLING PLAINS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED AFTER 4 PM THIS AFTERNOON INTO
THE EVENING.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LUBBOCK TX
327 PM CDT MON APR 18 2005

TXZ021>025-027>031-190300-
BAILEY-BRISCOE-CASTRO-FLOYD-HALE-HALL-LAMB-MOTLEY-PARMER-SWISHER-
327 PM CDT MON APR 18 2005

THE STORM PREDICTION CENTER HAS ISSUED SEVERE THUNDERSTORM WATCH
NUMBER 160 UNTIL 10 PM CDT FOR THE FOLLOWING COUNTIES...

PARMER... SWISHER... CASTRO... BRISCOE... HALL...
BAILEY... LAMB... HALE... FLOYD... AND MOTLEY.

THIS INCLUDES THE COMMUNITIES OF...
FRIONA... DIMMITT... TULIA... SILVERTON... MEMPHIS...
MULESHOE... LITTLEFIELD... PLAINVIEW... FLOYDADA AND MATADOR.

SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA MAY PRODUCE
HAIL UP TO 2 INCHES IN DIAMETER AND WINDS UP TO 70 MPH.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 60 STATUTE MILES
EAST AND WEST OF A LINE FROM 30 MILES SOUTHWEST OF PLAINVIEW TEXAS
TO 55 MILES NORTH NORTHEAST OF LIBERAL KANSAS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE
FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN
THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS.
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES.

JW