NWS-SPC: Public Severe Weather Outlook

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK 0540 AM CDT WED JUN 06 2007

...SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE NORTHERN PLAINS LATER TODAY AND TONIGHT...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING A MODERATE RISK FOR THE DEVELOPMENT OF TORNADOES...LARGE HAIL AND DAMAGING WINDS OVER PARTS OF THE NORTHERN PLAINS LATER TODAY AND TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE A SMALL PART OF NORTHWEST IOWA WESTERN MINNESOTA MUCH OF SOUTHERN AND EASTERN NORTH DAKOTA NORTHEAST INTO CENTRAL NEBRASKA MUCH OF SOUTH DAKOTA

SURROUNDING THE MODERATE RISK AREA...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF THE REMAINDER OF THE NORTHERN INTO CENTRAL PLAINS.

A VERY STRONG UPPER LEVEL TROUGH LOCATED OVER THE INTERMOUNTAIN WEST THIS MORNING...ACCOMPANIED BY UNSEASONABLY STRONG DEEP LAYER WIND FIELDS...IS FORECAST TO MOVE INTO THE NORTHERN AND CENTRAL PLAINS LATER TODAY THROUGH TONIGHT.
A STRONG SURFACE LOW WILL DEVELOP AND TRACK FROM SOUTHEAST MONTANA TOWARD SOUTHEAST NORTH DAKOTA BY THURSDAY MORNING.

SOUTHERLY LOW LEVEL WINDS WILL ALLOW MOISTURE TO RETURN RAPIDLY NORTHWARD ACROSS THE PLAINS AHEAD OF A DRY LINE WHICH WILL DEVELOP EASTWARD INTO THE WESTERN PART OF THE PLAINS. UNSEASONABLY COLD AIR ALOFT ATOP THIS INCREASING SURFACE MOISTURE WILL CONTRIBUTE TO FAVORABLE CONDITIONS FOR SEVERE THUNDERSTORMS.

AN AREA OF WARM AIR LOCATED JUST OFF THE SURFACE WILL LIMIT THUNDERSTORM DEVELOPMENT UNTIL LATE TODAY AS STRONG HEATING AND LIFTING AHEAD OF APPROACHING WEATHER SYSTEM COINCIDE. THE APPROACH OF THE UPPER TROUGH WILL SUPPORT THUNDERSTORM DEVELOPMENT INITIALLY ACROSS WESTERN PARTS OF THE NORTHERN PLAINS DURING THE LATE AFTERNOON.

STRONG WIND FIELDS CHANGING DIRECTION WITH HEIGHT WILL BE SUPPORTIVE FOR SUPERCELLS PRODUCING TORNADOES...LARGE HAIL AND DAMAGING WINDS.

INITIAL THUNDERSTORMS WILL THEN EVOLVE INTO A SQUALL LINE THIS EVENING THROUGH TONIGHT. THIS SQUALL LINE WILL TRACK NORTHEAST TOWARD THE EASTERN DAKOTAS/FAR NORTHWEST IOWA AND WESTERN MINNESOTA AND LIKELY PRODUCE A GREATER THREAT FOR DAMAGING WINDS.

THOSE IN THE THREATENED AREA ARE URGED TO REVIEW SEVERE WEATHER SAFETY RULES AND TO LISTEN TO RADIO...TELEVISION...AND NOAA WEATHER RADIO FOR POSSIBLE WATCHES...WARNINGS...AND STATEMENTS LATER TODAY.

..PETERS/EVANS.. 06/06/2007