Epic Outbreak of Tornadoes Across the Southeast on 27-28 April 2011 Impacts Northeast Georgia and Western North Carolina

Snow Across the Great Lakes, Central Appalachians, and Northeast; Unsettled Weather in the West

Light to moderate snow will continue into Saturday over the Great Lakes, Central Appalachians, and Northeast. This weekend into next week, a series of atmospheric rivers will bring gusty winds, periods of heavy rain, and mountain snow to northern California and the Pacific Northwest. Colder temperatures are in store for the weekend from the Great Lakes to East Coast. Read More >

SPC AC 260600 DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT TUE APR 26 2011 VALID 271200Z - 281200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS A LARGE PORTION OF KENTUCKY AND TENNESSEE...NORTHEAST AND EAST CENTRAL MISSISSIPPI...THE NORTHERN HALF OF ALABAMA...AND NORTHWEST GEORGIA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER GREAT LAKES REGION SWWD TO THE CENTRAL GULF COAST... ...SYNOPSIS... A LARGE UPPER TROUGH INITIALLY OVER THE CENTRAL U.S. IS FORECAST TO MAKE SLOW BUT STEADY EWD PROGRESS THIS PERIOD...WITH A POTENT SPEED MAX FORECAST TO ROUND THE BASE OF THE TROUGH AND SHIFT ACROSS THE MID SOUTH INTO THE OH VALLEY REGION WITH TIME. AT THE SURFACE...A DEEPENING LOW IS FORECAST TO SHIFT FROM THE VICINITY OF AR EARLY NNEWD TO THE GREAT LAKES REGION...WHILE A TRAILING COLD FRONT ACCELERATES EWD ACROSS THE OH/TN/MID AND LOWER MS VALLEYS. BY THE END OF THE PERIOD...THE FRONT SHOULD CROSS THE APPALACHIANS -- WITH A ZONE BETWEEN THE MS RIVER AND THE APPALACHIAN CREST LIKELY TO SEE A WIDESPREAD/POTENTIALLY DANGEROUS SEVERE WEATHER EVENT THIS PERIOD. ...LOWER GREAT LAKES REGION SWWD TO THE CENTRAL GULF COAST... ***POTENTIAL FOR A SIGNIFICANT/WIDESPREAD SEVERE WEATHER EVENT -- INCLUDING THE POSSIBILITY OF A TORNADO OUTBREAK -- REMAINS EVIDENT THIS FORECAST...CENTERED ON THE MID SOUTH/TN VALLEY AREA.*** SOME QUESTIONS EXIST ATTM WITH RESPECT TO CONVECTIVE EVOLUTION THIS PERIOD...CENTERED AROUND THE ONGOING STORMS PROGGED TO BE SHIFTING ACROSS ERN AR AND INTO WRN TN/NRN MS AT THE START OF THE PERIOD. WHILE THE COVERAGE AND PROGRESSION OF THIS CONVECTION COULD HAVE EFFECTS ON TIMING/LOCATION OF LATER DAY STORMS AS WELL AS THE QUALITY OF AIRMASS IN SOME AREAS...IT APPEARS ATTM THAT EARLY STORMS SHOULD CONTINUE ENEWD ACROSS WRN KY/WRN TN/NRN MS THROUGH THE MORNING...POSSIBLY WEAKENING SOME WITH TIME. HOWEVER...AS HEATING OF THE MOIST BOUNDARY LAYER COMMENCES AHEAD OF THE ADVANCING FRONT AND ASSOCIATED UPPER FEATURE AND AWAY FROM ANY CONVECTIVELY-COOLED AREAS...STORM REINTENSIFICATION AND NEW STORM DEVELOPMENT WILL BE LIKELY BY EARLY AFTERNOON. STRONG SLY SURFACE FLOW AHEAD OF THE FRONT INCREASING TO 80 TO 100 KT FROM THE SW AT MID LEVELS WILL PROVIDE SHEAR HIGHLY FAVORABLE FOR VERY INTENSE/LONG-LIVED ROTATING UPDRAFTS. THIS -- COMBINED WITH FAVORABLE THERMODYNAMIC ENVIRONMENT...APPEARS SUPPORTIVE OF SIGNIFICANT LONG-TRACK TORNADOES AND -- DEPENDING UPON STORM MODE -- THE THREAT FOR WIDESPREAD/VERY DAMAGING WINDS ALONG WITH LARGE HAIL. ATTM...GREATEST POTENTIAL FOR TORNADOES APPEARS TO EXIST ACROSS TN/KY/NRN MS AND NRN AND CENTRAL AL...WHILE POTENTIAL FOR WIDESPREAD WIND DAMAGE -- ALONG WITH TORNADO THREAT -- WILL EXTEND NNEWD ACROSS THE OH VALLEY TOWARD THE LOWER GREAT LAKES REGION AHEAD OF THE FRONT. OVERNIGHT...SOME TORNADO POTENTIAL WILL CONTINUE...THOUGH STORMS MAY BECOME MORE LINEAR AHEAD OF THE ACCELERATING FRONT AS IT MOVES TO -- AND POSSIBLY ACROSS -- THE APPALACHIANS. EXPECT POTENTIAL FOR DAMAGING WINDS TO PERSIST WITH THE CONVECTIVE LINE...GIVEN THE OVERALL STRENGTH OF THE LARGE-SCALE SYSTEM. ..GOSS.. 04/26/2011 CLICK TO GET WUUS02 PTSDY2 PRODUCT NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z