090  
ACUS01 KWNS 091648  
SWODY1  
SPC AC 091646  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1146 AM CDT THU MAY 09 2024  
 
VALID 091630Z - 101200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL  
TEXAS EAST ACROSS THE CENTRAL GULF COAST STATES AND INTO SOUTHERN  
GEORGIA AND SOUTHERN SOUTH CAROLINA...  
   
..SUMMARY
 
 
VERY LARGE HAIL WITH MULTIPLE SUPERCELLS APPEARS PROBABLE ACROSS  
PARTS OF NORTH AND CENTRAL TEXAS INTO THE ARKLATEX VICINITY THIS  
AFTERNOON AND EVENING. A BROADER CORRIDOR OF SEVERE HAIL AND  
DAMAGING-WIND POTENTIAL WILL EXTEND FROM EAST TEXAS INTO THE LOWER  
MISSISSIPPI VALLEY AND SOUTHEAST.  
   
..SYNOPSIS
 
 
WATER-VAPOR IMAGERY LATE THIS MORNING SHOWS A MID-LEVEL TROUGH OVER  
THE WESTERN GREAT LAKES/UPPER MS VALLEY AND A MID- TO UPPER-LEVEL  
LOW SITUATED OVER EASTERN UT. A BROAD BELT OF STRONG WESTERLY  
500-MB FLOW WILL EXTEND FROM THE DESERT SOUTHWEST EASTWARD ACROSS  
THE SOUTHERN GREAT PLAINS AND TO THE MID-ATLANTIC AND SOUTHEAST U.S.  
COAST. SATELLITE IMAGERY ALSO DEPICTS AN EMBEDDED DISTURBANCE  
QUICKLY MOVING EAST ACROSS AL INTO WESTERN GA LATE THIS MORNING.  
ANOTHER UPSTREAM DISTURBANCE IS CURRENTLY MOVING EAST-NORTHEAST  
ACROSS NORTHERN MEXICO INTO THE RIO GRANDE VALLEY/EDWARDS PLATEAU  
LATE THIS MORNING. IN THE LOW LEVELS, A SURFACE LOW OVER THE OH  
VALLEY IS LARGELY DISPLACED FROM THE AREA OF GREATEST SEVERE  
THUNDERSTORM CONCERN TODAY, WHICH IS LOCATED FROM TX EAST TO THE  
GA/SC VICINITY. A MYRIAD OF ONGOING THUNDERSTORM BANDS AND  
CONVECTIVE OUTFLOW OVER THE SOUTHEAST WILL SERVE AS CORRIDORS FOR  
ADDITIONAL AND CONTINUED THUNDERSTORM ACTIVITY THROUGH AT LEAST THE  
EARLY TO MID AFTERNOON. FARTHER WEST, A DRYLINE AND WEST-EAST  
ORIENTED FRONTAL ZONE OVER NORTH TX EAST TO THE ARKLAMISS WILL ALSO  
ACT TO FOCUS SEVERE THUNDERSTORM DEVELOPMENT LATER TODAY AND  
TONIGHT.  
   
..NORTH, CENTRAL AND EAST TX
 
 
SCATTERED THUNDERSTORMS ARE FORECAST TO DEVELOP THIS AFTERNOON AND  
EVENING AHEAD OF THE AFOREMENTIONED MID-LEVEL DISTURBANCE ACROSS  
CENTRAL AND EVENTUALLY INTO EASTERN PORTIONS OF TX. STORM  
DEVELOPMENT WILL LIKELY INITIALLY FAVOR NEAR AND NORTH OF A FRONTAL  
ZONE DRAPED ACROSS NORTH TX WITH DRYLINE STORMS LATER THIS  
AFTERNOON. THE FORT WORTH AND DEL RIO, TX RAOBS SAMPLED 8-9 DEG  
C/KM 700-500 MB LAPSE RATES. VERY LARGE CAPE VIA A VERY MOIST  
BOUNDARY LAYER WILL LIKELY FAVOR EXPLOSIVE UPDRAFT GROWTH AS STORMS  
QUICKLY BECOME SUPERCELLULAR. LOW-LEVEL SHEAR WILL LIKELY BE  
SUBDUED DUE TO LACK OF A STRONG LOW-LEVEL MASS RESPONSE, THEREBY  
ACTING TO LIMIT OVERALL TORNADO POTENTIAL. NONETHELESS, A FEW  
SUPERCELLS WITHIN AN ENVIRONMENT CHARACTERIZED BY VERY LARGE  
BUOYANCY AND MOIST LOW LEVELS WILL POTENTIALLY YIELD SOME TORNADO  
RISK VIA LOCAL STORM-SCALE PROCESSES SUCH AS MERGERS AND BOUNDARY  
INTERACTIONS. LARGE TO GIANT HAIL --POTENTIALLY 3+ INCHES IN  
DIAMETER -- AS WELL AS LOCALLY SEVERE GUSTS AND PERHAPS A TORNADO OR  
TWO WILL BE THE PRIMARY THREATS. THE WIND THREAT COULD EVOLVE  
UPSCALE AND START FORWARD-PROPAGATING EASTWARD INTO LA WHEREVER  
EARLY CELLS CAN AGGREGATE INTO CLUSTERS. QLCS TORNADOES ARE ALSO  
POSSIBLE WITH ANY MCS.  
   
..SOUTHEAST
 
 
BANDS OF STRONG TO SEVERE THUNDERSTORMS ONGOING DURING THE MIDDAY  
WILL LIKELY CONTINUE TO PROPAGATE EAST-SOUTHEAST ACROSS EASTERN AL  
INTO GA AND SC. A VERY MOIST/UNSTABLE AIRMASS EVIDENT IN THE 12Z  
BIRMINGHAM AND ATLANTA RAOBS (1800 AND 1300 J/KG MLCAPE) WILL  
CONTINUE TO GRADUALLY DESTABILIZE, DESPITE CONSIDERABLE CLOUD  
COVERAGE ACROSS AL/GA. FEWER CLOUDS ACROSS SOUTH-CENTRAL GA INTO  
THE COASTAL PLAIN OF SC WILL CONTINUE TO HEAT MORE RAPIDLY  
DOWNSTREAM OF THE ONGOING STORMS AND YIELD AN ENVIRONMENT FAVORABLE  
FOR A CONTINUED DAMAGING-WIND RISK THROUGH THE MID TO LATE  
AFTERNOON. FOR SHORT-TERM CONVECTIVE DETAILS AND ENVIRONMENTAL  
ANALYSIS, PLEASE REFER TO MCD #728 AND FORTHCOMING MCDS OVER THE  
REGION.  
 
FARTHER WEST, FROM WESTERN AL WESTWARD INTO LA THIS AFTERNOON, WEAK  
LARGE-SCALE SUBSIDENCE IN WAKE OF THE AL/GA IMPULSE WILL PROBABLY  
ACT TO LIMIT STORM COVERAGE DURING THE DAY. ISOLATED SEVERE STORMS  
ARE POSSIBLE AS THE AIRMASS CONTINUES TO DESTABILIZE AND POTENTIALLY  
YIELD AN ISOLATED HAIL/WIND THREAT. LATER THIS EVENING INTO THE  
OVERNIGHT, A CLUSTER OF THUNDERSTORMS IS FORECAST TO EVOLVE OVER THE  
ARKLATEX AND MOVE EAST ACROSS LA INTO MS AND EVENTUALLY MS/AL/FL  
PANHANDLE. SEVERE GUSTS (60-85 MPH) AND THE RISK FOR A FEW  
TORNADOES WILL PROBABLY ACCOMPANY THIS ACTIVITY AS IT MOVES EAST  
DURING THE EVENING AND OVERNIGHT.  
   
..MID/UPPER OHIO VALLEY TO TIDEWATER
 
 
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE THIS  
AFTERNOON ACROSS PORTIONS OF THE OH VALLEY, WITH DAMAGING GUSTS AND  
MARGINALLY SEVERE HAIL POSSIBLE. SOME HEATING COUPLED WITH LOWER  
60S SURFACE DEWPOINTS WILL CONTRIBUTE TO MLCAPE RANGING FROM  
500-1500 J/KG. THOUGH UPPER FLOW WILL BE STRONG, NEARLY  
UNIDIRECTIONAL PROFILES AND LACK OF GREATER MIDLEVEL WINDS SHOULD  
KEEP EFFECTIVE-SHEAR MAGNITUDES IN THE 30-40 KT RANGE OVER MUCH OF  
THE AREA.  
 
FARTHER EAST/SOUTHEAST, COOL/STABLE AIR NORTH OF A DAMMING/PRECEDING  
FRONTAL ZONE ACROSS VA AND THE DELMARVA SHOULD LIMIT THE NORTHERN  
END OF SEVERE POTENTIAL. DESTABILIZATION AND AVAILABLE MOISTURE  
WILL BE SUBSTANTIALLY LIMITED TODAY IN THE NOMINAL WARM SECTOR,  
BETWEEN THE DAMMING FRONT AND A GREAT DEAL OF MCS/OUTFLOW ACTIVITY  
TO THE SOUTH OVER THE CAROLINAS/GA. THEREFORE, WHILE THUNDERSTORMS  
ARE POSSIBLE THIS AFTERNOON AND DEEP SHEAR MAY BE ADEQUATE FOR A FEW  
ORGANIZED CELLS, SEVERE POTENTIAL APPEARS ISOLATED.  
 
..SMITH/JEWELL.. 05/09/2024  
 

 
 
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