Severe Thunderstorm Warning 9, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
311 PM CST THU FEB 15 2001

COLD FRONT CURRENTLY WORKING ITS WAY SLOWLY SOUTHEASTWARD THROUGH THE
NORTHWEST HILL COUNTRY AT THIS TIME. THE TEMPERATURE AT JCT HAS DROPPED 10
DEGREES IN THE PAST HOUR WITH THE FROPA. FRONT SHOULD PUSH AWAY FROM THE AREA
BY THIS EVENING WITH THE NEXT FEATURE OF INTEREST BEING THE MAIN UPPER LEVEL
SYSTEM WHICH IS CURRENTLY SPINNING ACROSS SOUTHWESTERN NEW MEXICO.

WATER VAPOR IMAGERY SHOWING ABUNDANT MOISTURE STILL BEING PUMPED NORTHWARD IN
ADVANCE OF THE APPROACHING LOW. THE MODELS BRING THE FEATURE ACROSS CENTRAL
ZONES IN THE FORM OF AN OPEN WAVE WITH A RATHER STRONG VORT CENTER. AVN IS A
TOUCH SLOWER THAN THE ETA SOLUTION WITH BOTH MODELS BRINGING AN IMPRESSIVE
SLUG OF PVA OVER THE ENTIRE AREA TONIGHT. WOULD ORDINARILY TREND TOWARD
HIGHER POPS WITH THE FORECAST BUT WITH THE SUB PAR MODEL PERFORMANCE WITH
THIS SYSTEM WILL UNDERCUT GUIDANCE AND LEAN TOWARD CHANCE/LIKELY POPS. SHOULD
SEE PRECIP END OVER THE NORTH AND EAST TOMORROW MORNING SO WILL CONTINUE A
SLIGHT CHANCE FOR EASTERN AND SOUTHEASTERN ZONES. THE TYPE OF PRECIPITATION
MAY GET A BIT INTERESTING THIS EVENING AS CURRENT TEMPS ARE RUNNING JUST A FEW
DEGREES ABOVE FREEZING ACROSS THE BIG COUNTRY. LOOKING TO THE NORTHWEST
HOWEVER...TEMPERATURES AND DEWPOINTS ARE A BIT WARMER...COMPLIMENTS OF THE
SHALLOW DEPTH TO THE COLD AIR AND SUNSHINE. DEPTH OF COLD AIR WILL LIKELY
INCREASE TONIGHT AS THE UPPER LEVEL FEATURE APPROACHES. CAA AT THE SURFACE
HOWEVER LOOKS RATHER MINIMAL. THEREFORE...TEMPERATURES WILL LIKELY HOLD IN THE
LOWER 30S ACROSS THE BIG COUNTRY. DEPTH OF COLD AIR/MOISTURE AND LIFT DOES NOT
LOOK SUFFICIENT ENOUGH FOR SNOW. HOWEVER...LOOKS AS THOUGH SLEET MAY MIX WITH
THE RAIN AT TIMES BUT ACCUMULATIONS ARE NOT ANTICIPATED. WILL ALSO INCLUDE
THUNDERSTORMS OVER THE BIG COUNTRY AS LAPSE RATES EXCEED 7C WITH THE COLD POOL
ALOFT MOVING ACROSS. THUNDERSTORMS WILL ALSO BE POSSIBLE OVER THE SOUTHEAST
DUE TO THE BETTER PROXIIMITY TO THETA-E RIDGING OVER CENTRAL TEXAS.

OTHERWISE...SUNSHINE WILL RETURN TOMORROW WITH TEMPERATURES BACK UP INTO THE
50S. NGM MOS GUIDANCE LOOKS TOO WARM AS LOW LEVEL MOISTURE MAY REMAIN
SLIGHTLY ELEVATED DESPITE THE SUNSHINE.

IN THE EXTENDED...FORECAST TO REMAIN PRECIP FREE WITH SOME INCREASE IN
CLOUDINESS LIKELY BY THE MIDDLE OF NEXT WEEK.
q
PRELIM NUMBERS...
ABI 032/054/033/057 5100
SJT 037/057/033/059 5-00
JCT 045/060/032/061 6100

.SJT...NONE.

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TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
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WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
255 PM CST THU FEB 15 2001

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE OVER THE NORTHWEST HILL
COUNTRY THIS EVENING...SCATTERED NON SEVERE THUNDERSTORMS EXPECTED
OVER THE REMAINDER OF WEST CENTRAL TEXAS THIS EVENING AND
OVERNIGHT...

A COLD FRONT WAS LOCATED ACROSS THE NORTHERN EDWARDS PLATEAU AT MID
AFTERNOON. ARCTIC AIR COVERED MOST OF WEST CENTRAL TEXAS...NORTH OF
THE FRONT. SOUTH OF THE FRONT...WARM...MOIST AND UNSTABLE AIR
EXTENDED FROM THE TEXAS GULF COAST AND RIO GRANDE VALLEY...TO THE
NORTHWEST HILL COUNTRY.

WITH A WEAK MID LEVEL CAP IN PLACE...ISOLATED THUNDERSTORMS MAY
DEVELOP NEAR THE FRONT AND APPROACH QUICKLY APPROACH SEVERE LIMITS.
THE MAIN THREAT WILL BE TORNADOS...LARGE HAIL AND DAMAGING WINDS. AS
THE COLD FRONT MOVES SOUTH OF THE NORTHWEST HILL COUNTRY BY MID
EVENING...THE SEVERE WEATHER THREAT SHOULD END.

OVER THE REMAINDER OF WEST CENTRAL TEXAS...MOIST AND SLIGHTLY
UNSTABLE AIR WILL OVERRIDE THE ARCTIC AIRMASS IN PLACE NEAR THE
SURFACE. SCATTERED THUNDERSTORMS ARE EXPECTED TONIGHT...AS AN UPPER
LEVEL DISTURBANCE PASSES OVER WEST CENTRAL TEXAS. A FEW THUNDERSTORMS
MAY PRODUCE SMALL HAIL. DUE TO INSUFFICIENT INSTABILITY...SEVERE
THUNDERSTORMS ARE NOT EXPECTED.

SPOTTER ACTIVATION MAY BE REQUIRED OVER THE NORTHWEST HILL COUNTRY
THIS EVENING..

THIS OUTLOOK WILL RESUME SCHEDULED ISSUANCE ON MARCH 15 2001.
HOWEVER... THIS OUTLOOK WILL CONTINUE TO BE ISSUED AS NEEDED WHEN
THUNDERSTORMS THREATEN WEST CENTRAL TEXAS.

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140-154-155-168>170-160000-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK...CORRECTED TYPO
NATIONAL WEATHER SERVICE SAN ANGELO TX
307 PM CST THU FEB 15 2001

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE OVER THE NORTHWEST HILL
COUNTRY THIS EVENING...SCATTERED NON SEVERE THUNDERSTORMS EXPECTED
OVER THE REMAINDER OF WEST CENTRAL TEXAS THIS EVENING AND
OVERNIGHT...

A COLD FRONT WAS LOCATED ACROSS THE NORTHERN EDWARDS PLATEAU AT MID
AFTERNOON. ARCTIC AIR COVERED MOST OF WEST CENTRAL TEXAS...NORTH OF
THE FRONT. SOUTH OF THE FRONT...WARM...MOIST AND UNSTABLE AIR
EXTENDED FROM THE TEXAS GULF COAST AND RIO GRANDE VALLEY...TO THE
NORTHWEST HILL COUNTRY.

WITH A WEAK MID LEVEL CAP IN PLACE...ISOLATED THUNDERSTORMS MAY
DEVELOP NEAR THE FRONT AND QUICKLY APPROACH SEVERE LIMITS. THE MAIN
THREAT WILL BE TORNADOS...LARGE HAIL AND DAMAGING WINDS. AS THE COLD
FRONT MOVES SOUTH OF THE NORTHWEST HILL COUNTRY BY MID
EVENING...THE SEVERE WEATHER THREAT SHOULD END.

OVER THE REMAINDER OF WEST CENTRAL TEXAS...MOIST AND SLIGHTLY
UNSTABLE AIR WILL OVERRIDE THE ARCTIC AIRMASS IN PLACE NEAR THE
SURFACE. SCATTERED THUNDERSTORMS ARE EXPECTED TONIGHT...AS AN UPPER
LEVEL DISTURBANCE PASSES OVER WEST CENTRAL TEXAS. A FEW THUNDERSTORMS
MAY PRODUCE SMALL HAIL. DUE TO INSUFFICIENT INSTABILITY...SEVERE
THUNDERSTORMS ARE NOT EXPECTED.

SPOTTER ACTIVATION MAY BE REQUIRED OVER THE NORTHWEST HILL COUNTRY
THIS EVENING..

THIS OUTLOOK WILL RESUME SCHEDULED ISSUANCE ON MARCH 15 2001.
HOWEVER... THIS OUTLOOK WILL CONTINUE TO BE ISSUED AS NEEDED WHEN
THUNDERSTORMS THREATEN WEST CENTRAL TEXAS.

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TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-160000-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE SAN ANGELO TX
401 PM CST THU FEB 15 2001

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE OVER THE NORTHWEST
HILL COUNTRY AND NORTHERN EDWARDS PLATEAU THROUGH EARLY
EVENING...SCATTERED NON SEVERE THUNDERSTORMS ARE EXPECTED OVER THE
REMAINDER OF WEST CENTRAL TEXAS THIS EVENING AND OVERNIGHT...

A COLD FRONT HAD MOVED THROUGH ALL OF WEST CENTRAL TEXAS AS OF 4 PM.
ARCTIC AIR COVERED ALL OF WEST CENTRAL TEXAS...NORTH OF THE FRONT.

WARM...MOIST AND UNSTABLE AIR FROM SOUTH TEXAS AND NORTHERN MEXICO
WILL OVERRIDE THE ARCTIC AIRMASS OVER WEST CENTRAL TEXAS. AS AN UPPER
LEVEL DISTURBANCE ENTERS NEW MEXICO THIS EVENING...SCATTERED
THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE OVER WEST CENTRAL
TEXAS. A FEW THUNDERSTORMS MAY APPROACH SEVERE LIMITS SOUTH OF
INTERSTATE 10 THROUGH EARLY EVENING...WITH THE MAIN THREAT BEING
LARGE HAIL. OVER THE REMAINDER OF WEST CENTRAL TEXAS...A FEW
THUNDERSTORMS MAY PRODUCE SMALL HAIL THIS EVENING AND OVERNIGHT.

SPOTTER ACTIVATION MAY BE REQUIRED SOUTH OF INTERSTATE 10 THROUGH
EARLY EVENING..

THIS OUTLOOK WILL RESUME SCHEDULED ISSUANCE ON MARCH 15 2001.
HOWEVER... THIS OUTLOOK WILL CONTINUE TO BE ISSUED AS NEEDED WHEN
THUNDERSTORMS THREATEN WEST CENTRAL TEXAS.

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