796  
FOUS30 KWBC 070050  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
850 PM EDT FRI JUN 6 2025  
 
DAY 1  
VALID 01Z SAT JUN 07 2025 - 12Z SAT JUN 07 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
THE SOUTHERN PLAINS AND OHIO VALLEY...  
   
..TEXAS CAPROCK  
 
MULTIPLE SUPERCELLS WILL CONTINUE TO PLAGUE THE AREA WITHIN WFO  
LUBBOCK, TX CWA BOUNDS WITH CELLS ORIGINALLY FORMING WITHIN THE  
CAPROCK AND MOVING EASTWARD WITHIN THE MEAN LAYER FLOW. SUFFICIENT  
BUOYANCY AND SHEAR ACROSS THE SOUTHERN HIGH PLAINS WILL MAINTAIN  
SEVERE THUNDERSTORM POSTURE FOR AT LEAST ANOTHER 2-4 HOURS BEFORE  
ANY CONVECTION BEGINS TO COLLAPSE, OR EVEN INDUCE CELL MERGERS IN  
THE CASE OF THE ACTIVITY BETWEEN THE NM/TX STATE LINES THROUGH  
NORTHWEST TX. RAINFALL RATES BETWEEN 2-3"/HR WITH INTRA-HOUR RATES  
UP TO 5"/HR WILL LEAD TO FLASH FLOOD CONCERNS OVER AN AREA STILL  
RECOVERING FROM YESTERDAYS BARRAGE OF RAINFALL FROM A SIMILAR  
CONVECTIVE EVOLUTION. THE PREVIOUS SLGT WAS GENERALLY MAINTAINED  
WITH A MINOR EXPANSION TO THE NORTHERN EDGE TO ENCOMPASS LEFT-  
MOVING SUPERCELLS THAT ARE MAKING HEADWAY TOWARDS THE SOUTHERN  
PORTION OF THE PANHANDLE.  
   
..SOUTHERN PLAINS TO OZARKS  
 
A REPEAT OF THE PATTERN LAST EVENING WITH MULTIPLE MESOCYCLONES  
CURRENTLY SITUATED OVER THE SOUTHEAST CO FRONT RANGE WILL SHIFT  
SOUTHEAST WITH GENERAL MOTION WITH THE UPWIND PROPAGATION VECTOR. A  
DISTINCT SPLIT HEAVY RAIN AXIS WILL TRANSPIRE ACROSS THE EASTERN TX  
PANHANDLE INTO OK WITH ANOTHER ACROSS THE NORTHERN HALF OF OK INTO  
SOUTHERN KS AS THE CELLS EVENTUALLY MERGER INTO A LARGE MCS THAT  
WILL PROPAGATE SOUTHEAST TOWARDS EASTERN OK INTO THE NORTHWEST AR  
OZARKS BY THE END OF THE FORECAST. HEAVY RAINFALL BETWEEN 2-4" WITH  
LOCALLY AS HIGH AS 5" ARE FORECAST WITHIN THE CONFINES OF THE  
NORTHERN HALF OF THE EXPECTED COMPLEX, CROSSING THROUGH A REGION  
WITH SATURATED ANTECEDENT GROUNDS THANKS TO THE PREVIOUS MORNINGS  
MCS THAT HIT THE SAME AREAS AS EXPECTED TONIGHT. ANYWHERE FROM THE  
I-40 CORRIDOR ON NORTH WILL HAVE THE POTENTIAL FOR FLASH FLOODING  
DUE TO THE MCS WITH A HIGH-END SLGT RISK POSITIONED OVER THE OK/KS  
BORDER WHERE 1/3/6 HOUR FFG'S HAVE BEEN SIGNIFICANTLY DEGRADED FROM  
PREVIOUS ACTIVITY LAST NIGHT INTO THIS MORNING. THE SLGT RISK WAS  
EXPANDED ON THE NORTHERN EDGE FROM PREVIOUS UPDATE TO ATTRIBUTE TO  
THE LATEST HEAVY QPF FOOTPRINT ON THE UPWIND SIDE OF THE EXPECTED  
MCS DEVELOPMENT THIS EVENING.  
   
..OHIO VALLEY  
 
LARGE CLUSTER OF THUNDERSTORMS CAPABLE OF 1-2"/HR RATES WILL  
CONTINUE TO MANEUVER EASTWARD THROUGH THE OHIO RIVER BASIN DOWN  
INTO KY WITH A SECONDARY BATCH OF CONVECTION MOVING THROUGH TN WITH  
A FEW STRONGER CORES. SHORTWAVE ENERGY ASSOCIATED WITH THE CELL  
CONGLOMERATION WILL MOTION EASTWARD INTO THE CENTRAL APPALACHIAN  
FRONT LEADING TO SCATTERED HEAVIER CONVECTION TO SHUFFLE THROUGH  
THE OHIO RIVER BASIN AND KY INTO WV OVERNIGHT. SIGNALS FOR A FEW  
HEAVIER CELLS OVER THE TERRAIN OF EASTERN KY INTO WV HAVE BEEN  
STEADY IN THE CAMS THROUGH THE COURSE OF THE DAY WITH SOME AREAS  
ALREADY BEEN AFFECTED BY PREVIOUS HEAVY RAIN OUTPUT DURING THE D1  
TIME FRAME. FFG'S REMAIN RELATIVELY LOW IN THOSE AREAS FROM ALL THE  
PRIOR PRECIP WITH SOME AREAS LIKELY TO REACH OVER 2" IN 24 HRS FROM  
ALL THE CONVECTIVE IMPACT IN THE TIME PERIOD. CONSIDERING THE  
THREAT FOR HEAVY PRECIP IN BACK-TO-BACK POSTURE, A SLGT RISK WAS  
MAINTAINED OVER KY AND EXPANDED TO THE EAST TO INCLUDE WV WHERE  
HOURLY CAMS HAVE BEEN MORE AGGRESSIVE WITH HEAVIER QPF SIGNALS IN  
THE LATEST ITERATIONS.  
   
..WEST TEXAS  
 
SUFFICIENT SURFACE BASED INSTABILITY ON THE ORDER OF 2000-4000 J/KG  
HAS ALLOWED FOR SCATTERED THUNDERSTORMS DEVELOPMENT ACROSS  
SOUTHEAST NM DOWN THROUGH THE UPPER TRANS PECOS OF TX. MEAN STORM  
MOTIONS OF 15-20 KTS TO THE EAST SHOULD MAINTAIN RELATIVELY STEADY  
FORWARD MOMENTUM OF CONVECTION THROUGH THE EVENING, BUT ANY STRONG  
CONVECTIVE CORE COULD THROW OUT AN EASY 1-2" TOTAL WITHIN A SHORT  
PERIOD OF TIME LEADING TO LOCALIZED FLASH FLOOD CONCERNS OVER  
SOUTHEAST NM, NORTHWEST PERMIAN BASIN, DOWN THROUGH THE MOUNTAINS  
OF SOUTHWEST TX. A MRGL RISK REMAINS FOR THOSE AREAS, BUT WAS  
TRIMMED ON EITHER SIDE TO FIT A MORE NARROW AXIS WHERE STORMS COULD  
SURVIVE BEFORE HITTING A MORE CAPPED ENVIRONMENT NEAR THE PECOS  
RIVER AND POINTS EAST.  
 
KLEEBAUER  
 
DAY 2  
VALID 12Z SAT JUN 07 2025 - 12Z SUN JUN 08 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS THE LOWER  
ARKANSAS VALLEY, LOWER MISSISSIPPI VALLEY INTO THE LOWER TENNESSEE  
VALLEY...  
 
...EASTERN OKLAHOMA AND NORTHEAST TEXAS TO CENTRAL/NORTHERN  
ALABAMA...  
THE SECOND ROUND OF HEIGHT FALLS MOVING INTO THE CENTRAL  
TO SOUTHERN PLAINS DAY 1 WILL CONTINUE TO PUSH EAST SOUTHEAST  
TOWARD THE MID TO LOWER MS VALLEY, OH AND TN VALLEYS DURING DAY 2.  
UPPER DIFLUENCE IS FORECAST TO BE WELL DEFINED SATURDAY INTO  
SATURDAY NIGHT/EARLY SUNDAY IN AN AXIS OF ABOVE AVERAGE PW VALUES  
THAT WILL REMAIN ALONG THE WEST TO EAST ORIENTED FRONTAL BOUNDARY  
ACROSS THESE AREAS. THIS SHOULD SUPPORT POTENTIAL FOR ANOTHER ROUND  
OF ORGANIZED CONVECTION ALONG THIS FRONT AS WELL AS NEAR A WELL-  
DEFINED MID-LEVEL CIRCULATION PASSING TO THE NORTH INTO THE OHIO  
VALLEY. THERE IS SOME SPREAD WITH THE QPF AXES, BUT CONSENSUS THAT  
HEAVY AMOUNTS ARE POSSIBLE. THE INHERITED SLIGHT RISK AREA WAS  
SHIFTED A BIT SOUTH AND REMOVED FROM MOST OF TN GIVEN SOUTHERN  
TRENDS WITH THE EARLY MORNING MCS AND RELATED REDEVELOPMENT ALONG  
THE ASSOCIATED LINGERING OUTFLOW BOUNDARY THROUGH THE EARLY EVENING  
INTO NORTHEAST TX.  
   
..MIDDLE MISSISSIPPI AND OHIO VALLEYS  
 
MID-LEVEL WAVE EJECTING OUT OF THE CENTRAL PLAINS SATURDAY MORNING  
WILL CONTINUE TO PUSH EASTWARD ACROSS THE OHIO VALLEY. THIS  
FEATURE WILL AID IN INCREASED MOISTURE RETURN AND SHEAR TO PROVIDE  
FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. THE INHERITED  
MARGINAL RISK WAS EXPANDED NORTHWARD TO CAPTURE THIS TREND OF MORE  
PRECIPITATION ATTACHED TO THE MID-LEVEL LOW. A SLIGHT RISK MAY BE  
NECESSARY ACROSS THE OHIO VALLEY FROM SOUTHERN IL TO NORTHERN KY  
AND SOUTHERN OH, BUT THIS AREA IS CONDITIONAL ON WHETHER ENOUGH  
INSTABILITY CAN BUILD AHEAD OF THE MID-LEVEL SHORTWAVE PUSHING  
EASTWARD. SHOULD GUIDANCE COME INTO BETTER AGREEMENT THIS UPGRADE  
MAY BE NEEDED, WITH LATEST HREF PROBS FOR AT LEAST 2"/6-HR UP TO  
40%. ANTECEDENT CONDITIONS ARE ALSO RATHER WET, SO THAT WILL NEED  
TO BE CONSIDERED AS WELL WITH CURRENT CONVECTION FOR THE NEXT  
OVERNIGHT UPDATE.  
   
..NORTHEAST PA THROUGH NEW ENGLAND  
 
ANOTHER ROUND OF CONVECTION POSSIBLE EARLY DAY 2 ALONG THE FRONTAL  
BOUNDARY PUSHING THROUGH THE NORTHEAST AS A SHARPENING NORTHERN  
STREAM TROF PUSHES EASTWARD ACROSS NORTHERN NY INTO NEW ENGLAND.  
THE HREF NEIGHBORHOOD PROBABILITIES FOR THE 12 HOUR PERIOD FROM  
1200 UTC SATURDAY TO 0000 UTC SUNDAY, ARE HIGH ALONG THIS FRONT FOR  
1 AND 2"+ AMOUNTS. THE PREVIOUS MARGINAL RISK AREA WAS EXTENDED  
FARTHER WEST INTO NORTHEAST PA TO COVER THESE HIGHER 12 HOUR  
PROBABILITIES. THERE MAY NEED TO BE AN UPGRADE TO THE RISK LEVEL IN  
FUTURE ISSUANCES DEPENDING UPON WHERE THE HEAVY RAINS OCCUR DURING  
DAY 1.  
 
SNELL/ORAVEC  
 
DAY 3  
VALID 12Z SUN JUN 08 2025 - 12Z MON JUN 09 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS NORTHERN  
TEXAS AND SOUTHERN OKLAHOMA...  
   
..SOUTHERN PLAINS TO THE SOUTHEAST  
 
ADDITIONAL SHORTWAVE ENERGY LIKELY TO PUSH EAST SOUTHEASTWARD LATE  
SUNDAY AFTERNOON/EVENING FROM THE LEE OF THE CENTRAL TO SOUTHERN  
ROCKIES INTO THE SOUTHERN PLAINS UNDER THE INFLUENCE OF A MUCH  
STRONGER UPPER LEVEL LOW CENTERED OVER THE NORTH-CENTRAL UNITED  
STATES. THIS WILL AGAIN RE- STRENGTHEN THE LOW LEVEL FLOW INTO THE  
WEST TO EAST ORIENTED FRONT FORECAST TO REMAIN ACROSS THE SOUTHERN  
PLAINS, SUPPORTING ANOTHER ROUND OF ORGANIZED CONVECTION ALONG THE  
FRONT. THERE IS FAIRLY GOOD AGREEMENT ON THE DAY 3 QPF AXES IN THE  
MODELS. RESULTING IN GOOD CONTINUITY WITH THE SLIGHT RISK AREA  
WITH ONLY A SUBTLE EXPANSION AND SOUTH SHIFT WHERE WIDESPREAD RAINFALL  
AMOUNTS OF 2-4" ARE EXPECTED AND HIGHER AMOUNTS POSSIBLE.  
ADDITIONAL THUNDERSTORM ACTIVITY IS EXPECTED FROM EARLY MORNING  
CONVECTION AND AFTERNOON REDEVELOPMENT ALONG THE FRONTAL BOUNDARY  
THROUGH THE SOUTHEAST, WITH MOSTLY ISOLATED FLASH FLOODING  
CONCERNS.  
   
..CENTRAL APPALACHIANS AND UPPER OHIO VALLEY  
 
MEANWHILE, THE MID-LEVEL WAVE PROGRESSING ACROSS THE OHIO VALLEY ON  
DAY 2 WILL CONTINUE INTO THE CENTRAL APPALACHIANS AND NORTHERN  
MID-ATLANTIC WHILE INTERACTING WITH A LINGERING FRONTAL BOUNDARY.  
THIS WILL PRODUCE ADDITIONAL AREAS OF SCATTERED AREAS OF CONVECTION  
AND THE POTENTIAL FOR ISOLATED INSTANCES OF FLASH FLOODING WITHIN  
TYPICALLY SENSITIVE TERRAIN. THERE REMAINS HIGHER THAN AVERAGE  
UNCERTAINTY REGARDING THE SPEED OF THIS SYSTEM, WHICH COULD IMPACT  
THE EVENTUAL FLASH FLOOD RISK AREA.  
 
SNELL/ORAVEC  
 
DAY 1 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/94EPOINTS.TXT  
DAY 2 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/98EPOINTS.TXT  
DAY 3 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/99EPOINTS.TXT  
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