612  
FOUS30 KWBC 030743  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
343 AM EDT FRI OCT 3 2025  
 
DAY 1  
VALID 12Z FRI OCT 03 2025 - 12Z SAT OCT 04 2025  
 
...THERE'S A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
FLORIDA'S EAST COAST...  
   
..FLORIDA'S EAST COAST  
 
A CLOSED MID-LEVEL DISTURBANCE WILL DRIFT WESTWARD ACROSS THE  
FLORIDA PENINSULA AND INTO THE GULF OF MEXICO TODAY. THIS SYSTEM  
WILL BRING TROPICAL MOISTURE FROM IMELDA AND HUMBERTO WITH IT. AN  
INVERTED TROUGH ORIENTED ALONG THE FLORIDA COAST WILL INTERACT WITH  
THE MOISTURE ADVECTING INTO THE REGION AND FORCE SCATTERED  
THUNDERSTORM ACTIVITY THROUGHOUT THE DAY. MODEST INSTABILITY  
BETWEEN 500-1000 J/KG MUCAPE COULD PRODUCE QUARTER TO HALF INCH  
RATES OVER THE SLIGHT RISK AREA. PARTS OF CENTRAL AND SOUTHERN  
FLORIDA THAT HAVE RECEIVED BETWEEN 2-4 (ISOLATED 5) INCHES OF RAIN  
IN THE PAST 24 HOURS WILL BE ESPECIALLY SUSCEPTIBLE TO RUNOFF FROM  
TODAY'S STORMS. NEIGHBORHOOD EXCEEDANCE PROBABILITIES OF 5 INCHES  
ARE BETWEEN 20-40% ACROSS FLORIDA'S EAST COAST TODAY.  
   
..GREAT BASIN  
 
ADDITIONAL RAINFALL IS FORECAST TO OCCUR BENEATH THE UPPER LOW,  
WHICH WILL CONTINUE PROPAGATING THROUGH THE INTERIOR WEST TODAY.  
RECENT HEAVY RAINFALL OVER PORTIONS OF THE GREAT BASIN WILL LIKELY  
PRIME SURFACES FOR RUNOFF FROM ADDITIONAL PRECIPITATION. BURN  
SCARS IN CENTRAL AND SOUTHERN IDAHO CONTINUE TO BE OF CONCERN FROM  
TODAY'S STORMS, THE BULK OF WHICH SHOULD OCCUR THIS MORNING INTO  
AFTERNOON BEFORE THE UPPER LOW MOVES DIRECTLY OVER THE GREAT BASIN  
AND INSTABILITY WEAKENS. HREF EAS EXCEEDANCE PROBABILITIES OF OVER  
1 INCH ARE BETWEEN 15-35% OVER NORTHERN/CENTRAL NEVADA WHERE PWATS  
WILL BE BETWEEN 2-3 STANDARD DEVIATIONS ABOVE NORMAL.  
 
KEBEDE  
 
DAY 2  
VALID 12Z SAT OCT 04 2025 - 12Z SUN OCT 05 2025  
 
...THERE'S A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
FLORIDA'S EAST COAST...  
   
..FLORIDA'S EAST COAST  
 
THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP ALONG THE  
INVERTED TROUGH AXIS ORIENTED NORTH-SOUTH ALONG FLORIDA'S EAST  
COAST ON SATURDAY. MOISTURE WILL LIFT NORTH ALONG WITH THE MID-  
LEVEL DISTURBANCE. THE INHERITED SLIGHT AND MARGINAL RISK AREAS  
WERE MAINTAINED DUE TO A MOSTLY CONSISTENT SIGNAL FOR EXCESSIVE  
RAINFALL OVER THE EAST CENTRAL COAST. ENSEMBLE EXCEEDANCE  
PROBABILITIES OF 2 INCHES ARE BETWEEN 5-10% ACROSS THE MARGINAL  
RISK AREA. 48 HOUR TOTALS BETWEEN 3-5 INCHES (LOCAL 6") WILL LIKELY  
MAKE OVERCOMING FLASH FLOOD GUIDANCE A BIT EASIER.  
   
..CENTRAL GULF COAST  
 
THE SAME MOISTURE REGIME IMPACTING THE FLORIDA PENINSULA WILL FOCUS  
OVER THE CENTRAL GULF COAST THIS WEEKEND. MID-LEVEL VORTICITY WILL  
LIFT INTO THE AREA ON SATURDAY, PROVIDING FORCING FOR CONVECTION  
ALONG THE IMMEDIATE LOUISIANA/MISSISSIPPI COAST. ANYWHERE BETWEEN  
4-6 INCHES OF RAIN MAY OCCUR OVER FAR SOUTHEASTERN LOUISIANA  
THROUGH SATURDAY NIGHT. DESPITE 2" ENSEMBLE EXCEEDANCE  
PROBABILITIES BEING RELATIVELY LOW (5-10%), THE MULTI DAY NATURE  
OF THE RAINFALL COULD STILL PRODUCE ISOLATED INSTANCES OF FLASH  
FLOODING.  
 
KEBEDE  
 
DAY 3  
VALID 12Z SUN OCT 05 2025 - 12Z MON OCT 06 2025  
 
...THERE'S A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
THE CENTRAL GULF COAST AND THE SOUTHEAST COAST...  
   
..CENTRAL GULF COAST  
 
THE MID-LEVEL DISTURBANCE CONTINUES PROPAGATING WESTWARD TOWARD THE  
POSITIVELY TILTED UPPER TROUGH CENTERED OVER THE WEST ON SUNDAY.  
THUS, THE HEAVY RAINFALL THREAT WILL LIKELY BLEED OVER FROM  
SATURDAY EVENING INTO SUNDAY MORNING FOR PORTIONS OF THE CENTRAL  
GULF COAST, BEFORE DISSIPATING BENEATH DIMINISHED SUPPORT ALOFT.  
PWATS OF 2-2.5" AND INSTABILITY BETWEEN 500-1000 J/KG MUCAPE COULD  
CHURN OUT RAIN RATES BETWEEN 1-1.5"/HR SATURDAY MORNING INTO  
AFTERNOON. ENSEMBLE EXCEEDANCE PROBABILITIES OF 2 INCHES ARE  
BETWEEN 5-15% ALONG THE FAR SOUTHEASTERN LOUISIANA TO FLORIDA  
PANHANDLE CORRIDOR, WHICH SUPPORTS THE MARGINAL RISK AREA IN  
PLACE.  
   
..SOUTHEAST COAST  
 
INVERTED TROUGHING CONTINUES ALONG THE FLORIDA/SOUTHEAST COAST  
THROUGH THE LATTER PART OF THIS WEEKEND. ANOMALOUS MOISTURE (2-3  
STNDV) WILL CONTINUE INTERACTING WITH THE SURFACE BOUNDARY TO  
GENERATE SCATTERED TO ISOLATED THUNDERSTORMS ACROSS THE  
FLORIDA/GEORGIA COAST. RAINFALL TOTALS OF 1-3" ARE LIKELY ALONG  
THE FLORIDA/GEORGIA/SOUTH CAROLINA COAST ON SATURDAY. THE LATEST  
GUIDANCE HAS TRENDED AWAY FROM TROPICAL MOISTURE MAKING ITS WAY  
INLAND, THEREFORE A MARGINAL RISK WAS MAINTAINED FOR MUCH OF THE  
SOUTHEAST COAST.  
 
KEBEDE  
 
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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