Severe Thunderstorm Warning 37, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
300 PM CST SAT MAR 25 2000

WITH MOIST HUMID AIRMASS IN PLACE...TRIGGERING MECHANISMS FOR
CONVECTION WILL NEED TO BE FOUND IN THE LOW LEVELS AS UPPER LEVEL
RIDGE IS IN PLACE FROM 700 MB AND UPWARDS. A WEAK FRONTAL BOUNDARY IS
SITUATED ACROSS THE BIG COUNTRY...ROUGHLY PARALLEL TO I-20.
BAROCLINICITY AND LOW LEVEL CONVERGENCE ARE MINIMAL AT THIS TIME. THE
UPSHOT FOR CONVECTION WILL BE THE DIURNAL INSTABILITY AS PARTIAL
CLEARING THIS AFTERNOON WILL FURTHER DESTABILIZE THE ATMOSPHERE AS
CAPES INCREASE. CAPES ALREADY NEAR 3000 J/KG AT ABI AND LIS OF <-7
EXTEND NORTHEASTWARD. TO THE WEST...ANOTHER BOUNDARY IN THE FORM OF A
DRY LINE/TROUGH WILL PUSH EASTWARD ACROSS THE AREA TOMORROW MORNING.
LLJ IS DIFFICULT TO DEPICT AND THE ETA CONVERGENCE ACROSS THE
HEARTLAND APPEARS TO BE OVERDONE. HENCE...ETA QPF MAY BE WAY OVERDONE
AS WELL. WILL STEER MORE TOWARD THE MOS/FAN POPS WITH 20% TONIGHT
ACROSS MOST AREAS. DEPENDING ON DEVELOPMENT OF CONVECTION BETWEEN NOW
AND TRANSMISSION TIME...MAY NEED 30 POPS FOR THE BIG COUNTRY AND/OR
LESS THAN 20 POPS SOUTHERN AREAS. WILL ADJUST ZONES ACCORDINGLY AS
PER WATCH ISSUANCE.
OTHERWISE...A WARM DAY IN STORE TOMORROW AS WESTERLY WINDS IN THE
10-20 MPH RANGE COMBINE WITH THERMAL 850 RIDGING. WITH AMPLE SUNSHINE
BY AFTERNOON...85 TO 90 WILL BE WITHIN REACH. SLIGHTLY COOLER TEMPS
OVER EASTERN SECTIONS AS A LATER WIND SHIFT/DECREASE IN CLOUD COVER
IS EXPECTED. NOT AS WARM ON MONDAY AS NORTHWESTERLY FLOW ALOFT AND
LOWER THICKNESSES INFILTRATE THE REGION.
NEXT SHOT FOR PRECIPITATION WILL BE ON TUESDAY AND WEDNESDAY AS
ANOTHER UPPER LEVEL LOW DIVES ACROSS THE SOUTHWEST. MRF AND EURO
MODELS NOT IN PHASE AS FAR AS TIMING GOES WITH THIS EVENT. WILL GO
AHEAD AND LEAVE EXTENDED AS IS WITH A SLIGHT CHANCE OF TSTMS FOR
TUESDAY AND WEDNESDAY.

PRELIMS...

ABI 059/084/052/078 2100
SJT 058/088/052/083 1-00
JCT 059/089/051/084 1-00

.SJT...NONE.

21
N

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-260000-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
230 PM CST SAT MAR 25 2000

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS NORTH OF A BARNHART
TO MASON LINE THROUGH TONIGHT...

A WEAK STATIONARY FRONT NEAR INTERSTATE 20 WILL BE THE FOCUS FOR
SCATTERED THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING.
ADDITIONAL THUNDERSTORMS ARE EXPECTED SOUTH OF THE FRONT...INTO THE
CONCHO VALLEY AND HEARTLAND...BUT THESE THUNDERSTORMS ARE EXPECTED TO
BE MORE LIMITED IN COVERAGE. INSTABILITY AND WINDS ALOFT WILL BE
SUFFICIENTLY STRONG TO SUPPORT SEVERE THUNDERSTORM DEVELOPMENT OVER
WEST CENTRAL TEXAS THROUGH LATE TONIGHT. THE PRIMARY THREAT WILL BE
LARGE HAIL. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE.

SPOTTER ACTIVATION MAY BE REQUIRED..

FOR THE SOUTHWEST TEXAS AND SOUTHEAST NEW MEXICO OUTLOOK SEE
PRODUCT LBBSPSMAF. FOR THE SOUTH PLAINS OUTLOOK SEE PRODUCT
LBBSPSLBB. FOR THE CENTRAL OKLAHOMA OUTLOOK SEE PRODUCT OKCSPSOKC.
FOR THE NORTH TEXAS OUTLOOK SEE PRODUCT FTWSPSFTW. FOR THE SOUTH
CENTRAL TEXAS OUTLOOK SEE PRODUCT SATSPSSA}T.

14
N