ZCZC SPCPWOSPC ALL WOUS40 KWNS 151818 TXZ000-OKZ000-151700- PUBLIC SEVERE WEATHER OUTLOOK STORM PREDICTION CENTER NORMAN OK 115 PM CDT THU 15 MAY 2003 ...OUTBREAK OF SEVERE THUNDERSTORMS...INCLUDING A FEW STRONG TORNADOES...IS EXPECTED OVER PARTS OF THE SOUTHERN PLAINS THIS AFTERNOON THROUGH TONIGHT. THE STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE DEVELOPMENT OF A FEW STRONG TORNADOES...VERY LARGE HAIL...AND DAMAGING WINDS OVER PARTS OF SOUTHERN PLAINS LATER THIS AFTERNOON THROUGH TONIGHT. THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE: THE TEXAS PANHANDLE AND EXTREME NORTHWEST TEXAS WESTERN OKLAHOMA AND THE OKLAHOMA PANHANDLE OTHER MORE ISOLATED SEVERE THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE ACROSS NORTHEAST NEW MEXICO...SOUTHEAST COLORADO...SOUTHWEST KS...AND WEST CENTRAL TEXAS. A STRONG MID-UPPER LEVEL STORM SYSTEM IS MOVING EASTWARD ACROSS THE FOUR CORNERS REGION EARLY THIS AFTERNOON...AND THIS SYSTEM WILL CONTINUE EASTWARD TO THE TEXAS PANHANDLE AND WESTERN OKLAHOMA AREA TONIGHT. A SURFACE LOW PRESSURE CENTER IS DEVELOPING ACROSS NORTHEAST NEW MEXICO IN ADVANCE OF THE MID LEVEL STORM SYSTEM...AND THIS LOW SHOULD MOVE EASTWARD TO NORTHWEST TEXAS AND SOUTHWEST OKLAHOMA BY LATE TONIGHT. RICH LOW-LEVEL MOISTURE ACROSS TEXAS AND OKLAHOMA WILL BE DRAWN WESTWARD INTO THE TEXAS PANHANDLE AS THE SURFACE LOW PRESSURE CENTER STRENGTHENS...WHICH WILL RESULT IN AN INCREASINGLY FAVORABLE ENVIRONMENT FOR SEVERE THUNDERSTORMS BY LATE AFTERNOON. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID AFTERNOON OVER THE WESTERN TEXAS PANHANDLE AND SOUTHEAST CO...EXPANDING EAST AND SOUTHEASTWARD TOWARD SOUTHWEST OKLAHOMA BY TONIGHT. VERTICAL WIND SHEAR AND INSTABILITY WILL BOTH INCREASE ACROSS THE TEXAS PANHANDLE AND WESTERN OKLAHOMA THROUGH EARLY TONIGHT...THUS STORMS THAT DEVELOP DURING THE AFTERNOON SHOULD REMAIN SEVERE WELL AFTER DARK. A FEW STRONG TORNADOES...VERY LARGE HAIL...AND DAMAGING WINDS WILL ALL BE POSSIBLE WITH THESE STORMS THIS AFTERNOON AND EVENING ACROSS THE TEXAS PANHANDLE...AND TONIGHT ACROSS WESTERN OKLAHOMA AND EXTREME NORTHWEST TEXAS. THIS IS POTENTIALLY A VERY DANGEROUS SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO REVIEW SEVERE WEATHER SAFETY RULES AND TO LISTEN TO RADIO AND TELEVISION AND NOAA WEATHER RADIO FOR POSSIBLE WATCHES...WARNINGS AND STATEMENTS LATER TODAY. JOHN HART LEAD FORECASTER, STORM PREDICTION CENTER