Severe Thunderstorm Warning 169, NWS Amarillo, TX

TEXAS/OKLAHOMA PANHANDLES AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
300 PM CDT TUE JUL 29 1997

12Z 500MB ANALYSIS INDICATED NOTBALE DRY AIR ADVECTION OVER THE
SOUTH PANHANDLES. WV SAT SHOWED SOME DRYING ROTATING ON THE BACK
SIDE AND UNDERNEATH THE RIDGE. HOWEVER...LOW LEVEL MOISTURE REMAINED
VERY HIGH SO WE DO NOT EXPECT PRECIPITABLE WATER VALUES TO DROP TOO
MUCH. A SPECIAL FLIGHT AT 18Z INDICATE A CAPE VALUE AROUND 3400 J/KG
AND A LIFTED INDEX OF MINUS 8. IN ADDITION...THE SOUNDING INDICATED
SOME COOLING AT 500MB. ALSO...TAKING A QUICK WALK OUTSIDE WE WERE
GREETED TO TOWERING CUMULUS IN ALL QUADRANTS. RADAR INDICATED SOME
ISOLATED STORMS OVER THE SOUTHWEST ZONES.

FORECAST PROBLEM OF TODAY IS FLASH FLOODING TONIGHT. WE DO NOT THINK
FLOODING WILL BE A PROBLEM DUE TO THE HIGHEST POPS ARE FORECAST
OVER AREAS THAT DID NOT RECEIVE HEAVY RAIN YESTERDAY. HEAVY RAIN IS
POSSIBLE BUT SHOULD NOT BE A PROBLEM. QPF IS HINTING AT HEAVY
PRECIPITATION ALONG THE FRONTAL BOUNDARY TONIGHT SO WE WILL INCLUDE
THE WORDING HEAVY RAINFALL POSSIBLE IN THE EXTREME WEST AND SOUTH
FOR TONIGHT.

MODELS ARE IN GOOD AGREEMENT. THE COLD FRONT ACROSS THE SOUTH HALF
OF THE PANHANDLES WILL MOVE SLOWLY SOUTH OF THE CWA TONIGHT. UPPER
LEVEL RIDGE WILL CONTINUE TO BROADEN WEST OVER THE SOUTH PLAINS AND
ROCKIES WITH TIME.  UPSLOPE FLOW WILL DIMINISH SOMEWHAT WEDNESDAY
MORNING...HOWEVER TEMPERATURES WILL BE A LITTLE LOWER AND PATCHY FOG
AND LOW CLOUDS ARE POSSIBLE. WITH RESIDUAL LOW LEVEL MOISTURE AND
HEATING WEDNESDAY AFTERNOON...WIDELY SCATTERED THUNDERSTORMS ARE
POSSIBLE ACROSS THE CWA.  AT THE SURFACE ON THURSDAY...A BUBBLE HIGH
WILL BREAK OFF THE MAIN HIGH AND DRIER AIR WILL BE IN PLACE. IN
ADDITION...UPPER LEVELS WILL BE DRY AND THE CONVECTIVE THREAT WILL
BE LESSEN.  A LEFT-OVER FRONTAL BONDARY IN EASTERN NEW MEXICO MAY BE
FOCUS FOR SOME INITIATION...SO WE WILL KEEP POPS IN THE WEST FOR
THURSDAY. WE WILL BE BOLD AND TAKE POPS OUT FOR THE REST OVER THE
CWA FOR THURSDAY.

IN THE EXTENDED...MODELS KEEP THE RIDGE OVER CENTRAL U.S. THROUGH
THE WEEKEND. BETTER HEATING WILL PRODUCE SOME ISOLATED STORMS EARLY
IN THE FORECAST PERIOD. THE RIDGE WILL CONTINUE TO RETROGRA:DE
OVER THE ROCKIES BY MONDAY AND CHANCES WILL INCREASE DUE TO A
NORTHWEST FLOW.

.AMA...
TX...NONE.
OK...NONE.

ZEIGLER