Apr 25, 2014 0600 UTC Day 1 Convective Outlook

Apr 25, 2014 0600 UTC Day 1 Convective Outlook

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1132 PM CDT THU APR 24 2014

VALID 251200Z – 261200Z

…THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA…

…SUMMARY…
SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON ACROSS PARTS OF SOUTHEAST VIRGINIA AND INTO EASTERN NORTH CAROLINA…WHERE HAIL AND LOCALLY DAMAGING WINDS WILL BE THE MAIN THREATS. WHILE THE OVERALL TORNADO THREAT WILL REMAIN LIMITED ACROSS THE REGION…A TORNADO OR TWO WILL BE POSSIBLE ACROSS FAR SOUTHEAST VIRGINIA INTO NORTHEAST NORTH CAROLINA.

…SYNOPSIS…
A NEGATIVELY TILTED SHORTWAVE TROUGH OVER THE OHIO AND TENNESSEE VALLEYS THIS MORNING WILL SHIFT EASTWARD ACROSS THE APPALACHIANS DURING THE AFTERNOON BEFORE MOVING OFFSHORE AFTER 00Z/SATURDAY. AT THE SURFACE…WEAK LOW PRESSURE CENTERED OVER WESTERN OHIO WILL LIFT NORTHEAST ALONG THE LOWER GREAT LAKES…AND A TRAILING COLD FRONT EXTENDING SOUTHWARD FROM THE LOW WILL MOVE EWD ACROSS THE APPALACHIANS INTO THE VA/NC PIEDMONT BY 00Z SATURDAY. THUNDERSTORMS…SOME SEVERE…ARE EXPECTED TO DEVELOP AHEAD OF THIS FEATURE ACROSS SOUTHEAST VIRGINIA AND EASTERN NORTH CAROLINA.

ELSEWHERE…WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE ALONG THE PACIFIC NORTHWEST COAST INTO THE NORTHERN ROCKIES AND GREAT BASIN AS AN UPPER TROUGH STRENGTHENS/AMPLIFIES ALONG THE WEST COAST DURING THE AFTERNOON…BEFORE MOVING INLAND OVERNIGHT.

…SOUTHEAST VIRGINIA AND EASTERN NORTH CAROLINA…

WIDESPREAD SHOWERS AND THUNDERSTORMS WILL BE ONGOING ACROSS THE APPALACHIANS THIS MORNING AS UPPER LEVEL SHORTWAVE TROUGH TRACKS EWD TOWARD THE MID-ATLANTIC. A WARM FRONT WILL LIFT NORTHWARD ACROSS ERN NC TOWARD THE CHESAPEAKE WITH A WARM/MOIST AIRMASS SPREADING OVER THE PIEDMONT AND COASTAL PLAINS OF NC INTO SE VA. WEAK TO MODERATE DESTABILIZATION /LESS THAN 1800 J PER KG MUCAPE/ WILL OCCUR AS TEMPERATURES WARM INTO THE MID TO UPPER 70S F AND SFC DEW POINTS CLIMB INTO THE LOW…TO LOCALLY MID 60S F. MIDLEVEL LAPSE RATES WILL STEEPEN THROUGH THE AFTERNOON AS COOLING ALOFT OCCURS WITH THE APPROACH OF THE UPPER IMPULSE. STRONG SHEAR COINCIDENT WITH THE EXIT REGION OF THE MIDLEVEL JET WILL OVERSPREAD THE SLIGHT RISK AREA AND AID IN ORGANIZATION OF THUNDERSTORM UPDRAFTS. FORECAST SOUNDINGS INDICATE CYCLONICALLY CURVED…ALBEIT SMALL…LOW LEVEL HODOGRAPHS. THIS WILL MAINLY SUPPORT INSTANCES OF LARGE HAIL AND LOCALLY DAMAGING WINDS. HOWEVER…A TORNADO OR TWO IS POSSIBLE MAINLY ACROSS NE NC INTO EXTREME SE VA WHERE BACKED LOW LEVEL FLOW AND STRONGER PRE-FRONTAL CONVERGENCE IS EXPECTED TO BE MORE FAVORABLE. THE SEVERE THREAT SHOULD WANE QUICKLY WITH DIURNAL COOLING AND AS THE SYSTEM MOVES OFFSHORE.