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WWUS84 KOUN 021200

SPSOKC

OKZ004>048-050>052-TXZ083>090-021800-



HAZARDOUS WEATHER OUTLOOK

NATIONAL WEATHER SERVICE NORMAN OK

700 AM CDT WED MAY 2 2001



THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND

OVERNIGHT ACROSS PARTS OF WESTERN NORTH TEXAS... AND WESTERN AND

NORTHERN OKLAHOMA. THE RISK AREA IS NORTHWEST OF A LINE FROM

SEYMOUR... TO CHICKASHA... TO CUSHING. LARGE HAIL WILL BE THE

MAIN THREAT. SEVERE WEATHER POTENTIAL WILL CONTINUE TO SOME DEGREE

OVER PARTS OF OKLAHOMA AND NORTH TEXAS INTO THE WEEKEND.



A COLD FRONT WILL MOVE INTO NORTHWEST OKLAHOMA LATER TODAY... BEFORE

STALLING SOMEWHERE ACROSS WESTERN AND NORTHERN OKLAHOMA TONIGHT.

SOUTH WINDS AHEAD OF THE FRONT WILL CONTINUE TO PULL LOW LEVEL

MOISTURE NORTH INTO THE FRONTAL ZONE. DAYTIME HEATING... ALONG WITH

THE INCREASE IN MOISTURE... WILL CREATE MODERATELY UNSTABLE

CONDITIONS BY LATE AFTERNOON. MEANWHILE...THE DRY LINE HAS BECOME

BETTER DEFINED OVER WEST TEXAS THIS MORNING... AND WILL MOVE EAST

TO NEAR THE WESTERN BORDER OF OKLAHOMA BY EARLY EVENING.



WARM AIR AT MID LEVELS IS EXPECTED TO SUPPRESS THUNDERSTORM

DEVELOPMENT UNTIL LATE AFTERNOON OR EARLY EVENING... AT WHICH TIME

THUNDERSTORMS COULD FORM QUICKLY NEAR THE COLD FRONT AND THE DRY

LINE. A FAVORED AREA FOR INITIAL DEVELOPMENT WILL BE NEAR THE POINT

WHERE THE FRONT AND THE DRY LINE INTERSECT... MOST LIKELY IN OR NEAR

FAR SOUTHWEST OKLAHOMA. THUNDERSTORMS ARE EXPECTED TO INCREASE IN

NUMBER AND INTENSITY THIS EVENING... MOST LIKELY CONCENTRATING NEAR

THE DRY LINE... AND NEAR AND JUST NORTHWEST OF THE SURFACE FRONT.

STORMS WILL MOVE OR SPREAD NORTHEAST AT AROUND 25 MPH... AND COULD

LAST WELL INTO THE NIGHT ESPECIALLY OVER NORTHERN OKLAHOMA.



A DEVELOPING UPPER STORM SYSTEM OVER THE ROCKIES WILL RESULT IN

INCREASING WINDS AT ALL LEVELS TONIGHT. INCREASING SOUTH WINDS AT

LOW LEVELS... COUPLED WITH WEST TO SOUTHWEST WINDS ALOFT... WILL

CREATE A FAVORABLE WIND PROFILE FOR SEVERE THUNDERSTORMS. ANY

THUNDERSTORMS THAT MOVE SLOWLY WILL BE MORE CAPABLE OF DEVELOPING

INTO SUPERCELLS... WITH VERY LARGE HAIL... DAMAGING WINDS... AND

POSSIBLY A FEW TORNADOES. OTHERWISE... LARGE HAIL WILL BE THE

PRIMARY RISK OVER MOST OF THE SLIGHT RISK AREA.



THE STORM SYSTEM OVER THE ROCKIES WILL MOVE LITTLE THROUGH FRIDAY.

WEAKER DISTURBANCES ROTATING AROUND THE SYSTEM WILL MOVE ACROSS THE

AREA THURSDAY AND FRIDAY... MAINTAINING A RISK OF SEVERE WEATHER BOTH

DAYS. THE ENTIRE SYSTEM WILL BEGIN MOVING EAST BY SATURDAY... AND

WILL MAINTAIN A CHANCE OF THUNDERSTORMS THROUGH THE WEEKEND.



&&



EMERGENCY MANAGERS AND STORM SPOTTER GROUPS IN THE SLIGHT RISK AREA

SHOULD BE PREPARED FOR SEVERE WEATHER OPERATIONS THIS EVENING AND

OVERNIGHT... POSSIBLY BEGINNING AS EARLY AS 4 OR 5 PM THIS AFTERNOON.

CHANCES ALSO REMAIN GOOD THAT SPOTTER NETWORKS IN THE OKLAHOMA AND

NORTH TEXAS AREA WILL NEED TO BE ACTIVATED...POSSIBLY SEVERAL

TIMES... BETWEEN THURSDAY AND SUNDAY.



THERE ARE STILL UNCERTAINTIES REGARDING THE EXACT LOCATION OF THE

FRONT AND DRY LINE THIS EVENING. THERE IS A POSSIBILITY THAT SEVERE

WEATHER PARAMETERS MAY COME TOGETHER MORE FAVORABLY THIS EVENING OVER

ONE OR MORE SMALL AREAS WITHIN THE SLIGHT RISK. AT THIS TIME WE CAN

NOT PINPOINT THESE AREAS... BUT IF IT CAN BE DONE LATER TODAY...

PARTS OF THE SLIGHT RISK AREA COULD BE UPGRADED.



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