Severe Thunderstorm Warning 81, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
200 PM CDT THU MAY 15 1997

SATELLITE VIS IMAGERY SHOWS TWO POTENTIAL AREAS OF DEVELOPMENT LATE
THIS AFTERNOON...ONE IN THE VICINITY OF LBB AND ONE OVER THE NORTHERN
EDWARDS PLATEAU. ANALYSIS OF 850 MBS AT 12Z...OF WHICH I INCLUDED THE
DDC AND AMA OBS...SUGGESTS DEEP MOISTURE EXTENDING WELL INTO THE
PANHANDLE. MODIFIED SOUNDING AT MAF INDICATES A POTENTIAL FOR CAPES
TO REACH 4000 J/KG. THUS SEVERE POTENTIAL STILL EXISTS OVER THE AREA.

INTERESTINGLY...TWO PUBLIC REPORTS OF A TORNADO CAME IN LATE OVER
SUTTON COUNTY DUE TO TOWERING CUMULUS MOVING IN A COUNTER-CLOCKWISE
FORMATION. THUS MAY NEED TO ADDRESS FUNNEL CLOUDS/LANDSPOUTS IN
T-STORM OUTLOOK FOR THIS AREA.

WITH A PATTERN OF NORTHWEST FLOW...THE OMITTING OF DDC AND AMA
SOUNDINGS INTO THE ETA AND NGM MODELS THIS MORNING IS NOT GOOD NEWS.
WILL GIVE LITTLE CREDIBILITY TO THE DRIER NGM/ETA FORECASTS OF DRY
WEATHER TOMORROW. AVIATION MODEL BRINGS IN THE STRONGEST OF
SHORTWAVES LATE TOMORROW AFTERNOON...BUT ALL MODELS KEEP BETTER
MOISTURE AND DYNAMICS TO THE WEST. THIS FEATURE ACTUALLY SEEMS
REASONABLE GIVEN THUNDERSTORM INITIATION BEGAN FURTHER WEST THAN
ANTICIPATED YESTERDAY. WITH DEEP MOISTURE IN PLACE...WILL STILL FAVOR
MOSTLY CHANCE POPS AS SUGGESTED BY THE AVIATION MODEL. TEMPERATURES
ON THE OTHER HAND STILL APPEAR TOO COOL SO WILL RESORT TO NUMBERS
CLOSER TO NGM GUIDANCE.

ABI 059/083 32
SJT 059/085 33
JCT 058/086 43

OAKS

TXZ049-053-054-064>066-071>073-076>078-113-114-127-128-139-140-
154-155-168>170-161330-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
225 PM CDT THU MAY 15 1997

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS
AFTERNOON THROUGH THIS EVENING ACROSS ALL OF WEST CENTRAL TEXAS...

NUMEROUS OUTFLOW BOUNDARIES WILL INTERACT WITH DAYTIME HEATING...A
DEEP LAYER OF MOISTURE...AND UPPER LEVEL INSTABILITIES TO CREATE A
POTENTIAL FOR SEVERE THUNDERSTORMS ACROSS WEST CENTRAL TEXAS BY LATE
THIS AFTERNOON.

WITH STRONG INSTABILITY...ABUNDANT MOISTURE...AND MARGINAL WIND
SHEAR...THE MAIN SEVERE WEATHER THREAT WILL BE FOR LARGE HAIL AND
DAMAGING WINDS. HOWEVER...THUNDERSTORMS DEVELOPING ALONG THESE
BOUNDARIES WILL OCCASIONALLY BECOME TORNADIC.

IN ADDITION...BRIEF FUNNEL CLOUDS MAY DEVELOP THIS AFTERNOON OVER
SCHLEICHER... SUTTON...MENARD...AND KIMBLE COUNTIES DUE TO DAYTIME
HEATING INTERACTING WITH A SMALL LOW PRESSURE SYSTEM. THESE FUNNEL
CLOUDS ARE CAPABLE OF BRIEFLY REACHING THE GROUND CAUSING DAMAGING
WINDS. THE THREAT OF FUNNEL CLOUDS WILL DIMINISH OVER THESE AREAS
WITH THE LOSS OF DAYTIME HEATING.

SPOTTER ACTIVATION MAY BE REQUIRED.

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