Flash Flood Warning 50, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
141 PM CDT MON JUN 16 1997

HEAVY RAIN EVENT IS SETTING UP ACROSS WEST CENTRAL TEXAS THIS
EVENING.  CURRENT RADAR SHOWING A FEW THUNDERSTORMS ALREADY
DEVELOPING WEST OF CROCKETT COUNTY ALONG DRYLINE WHICH HAS TAKEN
SHAPE THIS AFTERNOON.  WEAK COLD FRONT IS STRETCHING ACROSS CENTRAL
OKLAHOMA TO SOUTH OF LUBBOCK.  TRIPLE POINT BOUNDARY INTERSECTION OF
DRYLINE AND FRONT IS SHOWING UP SOUTH OF LUBBOCK.  UPPER LOW
CONTINUES TO SPIN EASTWARD FROM NEW MEXICO TOWARD NORTHWEST TEXAS.
DEWPOINTS ARE IN UPPER 60S TO LOWER 70S ACROSS WEST CENTRAL TEXAS
WITH DEL RIO PRECIPITABLE WATER STILL ABOVE 2 INCHES.  ALL
INGREDIENTS ARE COMING TOGETHER FOR THUNDERSTORMS TO FORM ALONG
BOUNDARIES THIS AFTERNOON AND MOVE SOUTHWARD AND EASTWARD ACROSS THE
AREA.  WITH THE STEEP LAPSE RATES AS THE LOW MOVES ACROSS...CAPES
ABOVE 3000 J/KG AND AN UPPER LEVEL JET STREAK...WILL SEE SOME SEVERE
STORMS AS INDICATED BY DAY 1 OUTLOOK.  ALSO CONCERNED ABOUT HEAVY
RAIN AND FLASH FLOODING AS UPPER WINDS WILL BE PARALLEL TO FRONT AND
HIGH MOISTURE.  FLASH FLOOD GUIDANCE VALUES ARE LOW OVER MUCH OF THE
AREA FROM HEAVY RAIN DURING THE LAST WEEK.  THINK A FLASH FLOOD
WATCH IS WARRANTED FOR THE WHOLE AREA. LINE SHOULD SWEEP THROUGH BY
MORNING BRINGING PARTLY CLOUDY SKIES AND SLIGHTLY COOLER TEMPS FOR
TOMORROW AFTERNOON. WILL GO ABOVE GUIDANCE ON POPS AS MODELS LOOKING
A LITTLE TOO DRY. PREFER COOLER AVIhATION TEMPERATURES BASED ON THE
RAINFALL THREAT AND WEAK COLD AIR ADVECTION TOMORROW.

ABI 064/085 82
JCT 066/089 93
SJT 063/086 82

08

TXZ049-053-054-064>066-071>073-076>078-113-114-127-128-139-140-
154-155-168>170-181125-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
200 PM CDT MON JUN 16 1997

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS ALL OF
WEST CENTRAL TEXAS THIS AFTERNOON THROUGH TONIGHT...

A WARM AND VERY UNSTABLE AIR MASS WILL REMAIN IN PLACE ACROSS WEST
CENTRAL TEXAS THROUGH THIS EVENING. WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS HAVE BEGUN TO DEVELOP THIS AFTERNOON ALONG A DRYLINE
LOCATED WEST OF A LINE FROM OZONA TO MERTZON TO SWEETWATER.
ANY OF THESE STORMS COULD QUICKLY BECOME SEVERE...WITH LARGE HAIL AND
DAMAGING WINDS THE PRIMARY THREAT. HOWEVER...GIVEN THE FAVORABLE WIND
SHEAR ALOFT...A FEW OF THE STORMS COULD ALSO PRODUCE ISOLATED
TORNADOES. AS AN UPPER LEVEL LOW PRESSURE SYSTEM APPROACHES WEST
TEXAS DURING THE EVENING HOURS...THE STORMS ARE EXPECTED TO BECOME
MUCH MORE ORGANIZED. A LINE OF STRONG TO SEVERE STORMS IS EXPECTED TO
DEVELOP...WITH DAMAGING WIND GUSTS IN EXCESS OF 60 MPH AND LARGE HAIL
THE PRIMARY THREATS. THIS SQUALL LINE WILL LIKELY SWEEP ACROSS ALL OF
WEST CENTRAL TEXAS DURING THE EVENING AND EARLY MORNING HOURS.

IN ADDITION TO THE SEVERE WEATHER...THESE STORMS WILL ALSO PRODUCE
TORRENTIAL RAINFALL...WITH SEVERAL INCHES OF RAIN FALLING IN JUST A
FEW HOURS. WITH THE GROUND ALREADY SATURATED FROM EARLIER RAINS
...FLASH FLOODING WILL ALSO BE LIKELY...ESPECIALLY ALONG FLOOD PRONE
AREAS SUCH AS CREEKS AND STREAMS...DRAWS AND ARROYOS... AND
LOW WATER CROSSINGS.

EMERGENCY MANAGERS...RESIDENTS OF WEST CENTRAL TEXAS...AND PEOPLE
PLANNING OUTDOOR ACTIVITIES THIS EVENING...SHOULD MONITOR THIS
DEVELOPING DANGEROUS WEATHER SITUATION AND BE READY TO TAKE QUICK
ACTION IF A WARNING IS ISSUED.

SPOTTER ACTIVATION WILL LIKELY BE REQUIRED. FOR THE SOUTHWEST TEXAS
AND NEW MEXICO OUTLOOK SEE PRODUCT LBBSPSMAF. FOR THE SOUTH
PLAINS... THE WESTERN PARTS OF NORTH TEXAS... NORTH CENTRAL TEXAS...
AND SOUTH CENTRAL TEXAS OUTLOOKS SEE PRODUCTS LBBSPSLBB...
OKCSPSOKC... FTWSPSFTW... AND SATSPSSAT.
08

TXZ049-053-054-064>066-071>073-076>078-113-114-127-128-139-140-
154-155-168>170-171330-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK...CORRECTED RISK AREA
NATIONAL WEATHER SERVICE SAN ANGELO TX
232 PM CDT MON JUN 16 1997

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ALONG AND
EAST OF AN ALBANY...BAIRD...COLEMAN LINE LATE THIS AFTERNOON AND
EVENING...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE REST OF
WEST CENTRAL TEXAS THROUGH THIS EVENING...

A WARM AND VERY UNSTABLE AIR MASS WILL REMAIN IN PLACE ACROSS WEST
CENTRAL TEXAS THROUGH THIS EVENING. A DEVELOPING DRYLINE WILL
COMBINE WITH A VERY WEAK FRONTAL BOUNDARY TO PRODUCE SCATTERED
THUNDERSTORM ACTIVITY LATE THIS AFTERNOON...GENERALLY NORTHWEST OF
AN OZONA TO STERLING CITY TO SWEETWATER TO HAMLIN LINE. ANY OF THESE
STORMS COULD QUICKLY BECOME SEVERE...WITH LARGE HAIL THE PRIMARY
THREAT. HOWEVER...GIVEN THE FAVORABLE WIND SHEAR ALOFT...A FEW OF
THE STORMS COULD ALSO PRODUCE ISOLATED TORNADOES. AS AN UPPER LEVEL
LOW PRESSURE SYSTEM APPROACHES WEST TEXAS DURING THE EVENING
HOURS...THE STORMS ARE EXPECTED TO BECOME MUCH MORE ORGANIZED. A
LINE OF STRONG TO SEVERE STORMS IS EXPECTED TO DEVELOP...WITH
DAMAGING WIND GUSTS IN EXCESS OF 60 MPH AND LARGE HAIL THE PRIMARY
THREATS. THIS SQUALL LINE WILL LIKELY SWEEP ACROSS ALL OF WEST
CENTRAL TEXAS DURING THE EVENING AND EARLY MORNING HOURS.

IN ADDITION TO THE SEVERE WEATHER...THESE STORMS WILL ALSO PRODUCE
TORRENTIAL RAINFALL...WITH SEVERAL INCHES OF RAIN FALLING IN JUST A
FEW HOURS. WITH THE GROUND ALREADY SATURATED FROM EARLIER RAINS
...FLASH FLOODING WILL ALSO BE LIKELY...ESPECIALLY ALONG FLOOD PRONE
AREAS SUCH AS SMALL CREEKS AND STREAMS...DRAWS AND ARROYOS... AND
LOW WATER CROSSINGS.

SPOTTER ACTIVATION WILL LIKELY BE REQUIRED. FOR THE SOUTHWEST TEXAS
AND NEW MEXICO OUTLOOK SEE PRODUCT LBBSPSMAF. FOR THE SOUTH
PLAINS... THE WESTERN PARTS OF NORTH TEXAS... NORTH CENTRAL TEXAS...
AND SOUTH CENTRAL TEXAS OUTLOOKS SEE PRODUCTS LBBSPSLBB...
OKCSPSOKC... FTWSPSFTW... AND SATSPSSAT.