750  
FOUS30 KWBC 190101  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
801 PM EST TUE NOV 18 2025  
 
DAY 1  
VALID 01Z WED NOV 19 2025 - 12Z WED NOV 19 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN  
ARIZONA, FAR SOUTHEASTERN CALIFORNIA, AND FAR SOUTHEASTERN  
NEVADA...  
   
..SOUTHWEST U.S  
 
A SLIGHT RISK WAS MAINTAINED FOR PORTIONS OF WESTERN AZ AND  
IMMEDIATE ADJACENT AREAS OF SOUTHEAST CA AND SOUTHERN NV. A GENERAL  
DECREASE IN INSTABILITY IS EXPECTED TO RESULT IN A DOWNWARD TREND  
IN CONVECTIVE COVERAGE OVERNIGHT. HOWEVER, THE UPPER LOW WILL  
REMAIN TO THE WEST PROVIDING BROAD SYNOPTIC ASCENT AND LOW LEVEL  
MOISTURE TRANSPORT WILL ALSO PERSIST. A FEW POCKETS OF INSTABILITY  
SHOULD LINGER AS WELL...WHICH SHOULD BE ENOUGH TO ALLOW FOR  
ISOLATED LINEAR CONVECTIVE SEGMENTS TO PERSIST. THIS CONVECTION  
WILL CONTINUE TO LOCALLY TRAIN WITHIN THE DEEP LAYER SOUTHERLY  
FLOW, WITH A FEW INSTANCES OF 1"/HR RAINFALL POSSIBLE. SO WHILE  
THE OVERALL COVERAGE AND MAGNITUDE OF THE FLASH FLOOD RISK SHOULD  
BE ON THE DECLINE OVERNIGHT, LOCALIZED INSTANCES OF FLASH FLOODING  
WILL REMAIN POSSIBLE.  
   
..OHIO VALLEY  
 
WE WILL MAINTAIN A MARGINAL RISK ACROSS KY INTO NORTHERN TN.  
SCATTERED CONVECTION SHOULD CONTINUE AHEAD OF A COLD FRONT POSING  
A VERY LOCALIZED FLASH FLOOD RISK. IN GENERAL CELLS WILL EITHER BE  
QUICK ENOUGH MOVING OR NOT PRODUCING HIGH ENOUGH RATES TO RESULT  
IN FLASH FLOODING. HOWEVER SOME STRONGER CELLS, ESPECIALLY ON THE  
SOUTHWEST FLANK OF THE RISK AREA WHERE INSTABILITY IS GREATER,  
COULD LOCALLY PRODUCE 1-2"/HR RAINFALL. RAINFALL RATES ARE LOWER  
ON THE NORTHEAST SIDE OF THE RISK AREA, BUT MORE ANTECEDENT RAIN  
AND A BIT MORE PERSISTENCE OF THE RAIN HERE COULD STILL POSE A VERY  
ISOLATED THREAT.  
 
CHENARD  
 
DAY 2  
VALID 12Z WED NOV 19 2025 - 12Z THU NOV 20 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF  
SOUTH-CENTRAL TEXAS, THE CONCHO VALLEY, & THE TEXAS HILL COUNTRY...  
 
THE UPPER LEVEL TROUGH MOVING ACROSS THE SOUTHWEST US CONTINUES TO  
ALLOW FOR SUFFICIENT COVERAGE OF SCATTERED SHOWERS AND EMBEDDED  
THUNDERSTORMS INTO WEDNESDAY ACROSS THESE AREAS FOR A MARGINAL RISK  
THREAT LEVEL. LOCALIZED FLASH FLOODING COULD CONTINUE TO BE A  
CONCERN.  
 
ACROSS THE SOUTHERN PLAINS, LOW LEVEL-MOISTURE WILL BE DRAWN  
NORTHWARD WITH PRECIPITABLE WATER VALUES RISING INTO THE 1.5-1.75"  
RANGE, ABNORMALLY HIGH FOR MID-NOVEMBER. WHEN COMBINED WITH  
500-1500 J/KG OF MUCAPE AND 850 HPA INFLOW OF ~25 KTS, THE  
DEVELOPMENT OF ORGANIZED CONVECTION LATE WEDNESDAY NIGHT INTO  
EARLY THURSDAY MORNING IS BECOMING INCREASINGLY LIKELY IN AND NEAR  
SOUTH-CENTRAL TX. HOURLY RAIN AMOUNTS TO 2.5" AND LOCAL TOTALS TO  
5" ARE ANTICIPATED EARLY THURSDAY MORNING. THIS POTENTIAL LED TO A  
NEW SLIGHT RISK WHICH WAS COORDINATED WITH THE EWX/NEW BRAUNFELS  
AND SJT/SAN ANGELO FORECAST OFFICES. ITS FOOTPRINT WAS MOST IN LINE  
WITH THE 06Z REFS 30%+ CHANCE OF 3"+ AMOUNTS.  
 
ROTH  
 
DAY 3  
VALID 12Z THU NOV 20 2025 - 12Z FRI NOV 21 2025  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF  
THE SOUTHERN PLAINS INTO ARKANSAS/MISSOURI...  
   
..SOUTHERN PLAINS  
 
THE FLOW ALOFT BACKS OVER PORTIONS OF TEXAS AND OKLAHOMA AND  
BECOMES INCREASINGLY DIFFLUENT THURSDAY MORNING AS AN UPPER TROUGH  
MAKES ITS WAY FROM THE SOUTHERN GREAT BASIN INTO AND ACROSS THE  
SOUTHERN ROCKIES. THIS CONFIGURATION ALOFT WITH INCREASINGLY MOIST  
FLOW IN THE LOW LEVELS AHEAD OF A SURFACE COLD FRONT WILL FOSTER AN  
ENVIRONMENT PRODUCING EXCESSIVE RAINFALL BY MEANS OF INTENSE  
RAINFALL RATES BY INDIVIDUAL STORMS AND BY TRAINING OF CELLS/REPEAT  
CONVECTION. THE AXIS OF HIGHEST PRECIPITABLE WATER VALUES...  
1.5-1.75"...SETS UP OVER THE EASTERN HALF OF TEXAS INTO  
SOUTHEASTERNMOST OKLAHOMA AND ARKANSAS, WHICH IS WELL ABOVE  
AVERAGE FOR MID- NOVEMBER. LOCALIZED RAINFALL AMOUNTS UP TO 2.5" IN  
AN HOUR WITH ADDITIONAL LOCAL TOTALS OF 5" POSSIBLE WITHIN THIS  
SET UP WHICH WOULD RESULT IN SCATTERED INSTANCES OF FLASH FLOODING.  
CHANGES TO THE RISK AREAS WERE MOSTLY CONFINED WITH SOME PARING  
BACK OF THE SLIGHT ACROSS OK.  
 
   
..CALIFORNIA  
 
MAINTAINED A MARGINAL RISK AREA FROM CONTINUITY FOR PORTIONS OF  
COASTAL SOUTHERN CALIFORNIA AS THE NEXT AREA OF LOW PRESSURE  
PRODUCES ANOTHER ROUND OF ON-SHORE FLOW OF MOISTURE AND ASSOCIATED  
RAINFALL THURSDAY INTO EARLY FRIDAY. RAINFALL AMOUNTS AT THIS POINT  
LOOK TO BE PRETTY MODEST BUT WILL BE FALLING ON AREAS WHERE  
ANTECEDENT CONDITIONS HAVE BEEN WET FOR THE BETTER PART OF 5 DAYS.  
THAT MAY RESULT IN ADDITIONAL LOCALIZED FLOODING ON THURSDAY OR  
THURSDAY NIGHT.  
 
ROTH  
 
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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