The Good Friday Severe Weather Outbreak of April 10, 2009

Multi-day, Potentially Catastrophic Heavy Rainfall and Severe Weather Event

A multi-day, potentially historic heavy rainfall event may produce catastrophic and life-threatening flooding through Saturday from the Ozarks into the Ohio River Valley. Several clusters of strong to severe storms are expected from the Southern Plains, Mid Mississippi Valley to the Ohio/Tennessee Valleys and the Mid Atlantic. Read More >

MESOSCALE DISCUSSION 0440 NWS STORM PREDICTION CENTER NORMAN OK 0754 PM CDT FRI APR 10 2009 AREAS AFFECTED...CNTRL SC...FAR SRN NC CONCERNING...TORNADO WATCH 135... VALID 110054Z - 110200Z THE SEVERE WEATHER THREAT FOR TORNADO WATCH 135 CONTINUES. SUPERCELLS EMBEDDED WITHIN QLCS ACROSS UPSTATE SC/NERN GA SHOULD PROGRESS EWD WITH ATTENDANT THREATS FOR DAMAGING WINDS...ISOLATED TORNADOES AND HAIL. HOWEVER...THE ERN EXTENT OF THE SEVERE THREAT APPEARS UNCERTAIN GIVEN WEAKER INSTABILITY. AREA DOWNSTREAM OF WW 135 IS BEING MONITORED FOR EITHER A NEW WW OR POSSIBLE WFO AREAL EXTENSION. AS 0045Z...RADAR IMAGERY DEPICTED A QLCS STRETCHING FROM CHEROKEE COUNTY SC TO CLARKE COUNTY GA WITH SEVERAL EMBEDDED MESOCYCLONES AND BOWING SEGMENTS. THE OVERALL TREND FOR A LINEAR CONVECTIVE MODE SUGGESTS THAT DAMAGING WINDS SHOULD BECOME THE PRIMARY SEVERE THREAT...ALTHOUGH 0-1 KM SRH AOA 300 M2/S2 WILL SUPPORT POTENTIAL FOR ISOLATED TORNADOES. CURRENT QLCS TRACK SHOULD APPROACH THE ERN EXTENT OF WW 135 AROUND 02Z. HOWEVER...THE SEVERE THREAT SHOULD WANE FARTHER E AS THE ACTIVITY PROGRESSES E OF ANSON COUNTY NC TO ALLENDALE SC OWING TO AN APPARENT MARINE LAYER BOUNDARY NOTED EARLIER ON VIS/RADAR IMAGERY. INSTABILITY SHOULD BE QUITE LACKING E OF THIS LINE /AS DEPICTED IN 00Z CHS RAOB/. THUS...THERE IS UNCERTAINTY WHETHER A NEW WW WILL NEED TO BE ISSUED OR WHETHER A WFO-AREAL EXTENSION OF A FEW COUNTIES IN CNTRL SC WILL BE NEEDED. ..GRAMS.. 04/11/2009 ATTN...WFO...RAH...ILM...CHS...CAE...GSP...FFC... LAT...LON 35098152 35168040 34977945 34427927 33138027 32608115 32688203 33328254 34098255 34108244 35098152