449  
FOUS30 KWBC 171900  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
200 PM EST MON FEB 17 2025  
 
DAY 1  
VALID 12Z MON FEB 17 2025 - 12Z TUE FEB 18 2025  
 
THE PROBABILITY OF RAINFALL EXCEEDING FLASH FLOOD GUIDANCE IS LESS  
THAN FIVE PERCENT.  
 
GALLINA  
 
DAY 2  
VALID 12Z TUE FEB 18 2025 - 12Z WED FEB 19 2025  
 
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ALONG PORTIONS OF  
THE CENTRAL GULF COAST...  
   
..21Z OUTLOOK UPDATE  
 
RECENT MODELS (AND PARTICULARLY CAMS) DEPICT SUBSTANTIALLY  
INCREASED RAINFALL POTENTIAL (INTO THE 2-4 INCH RANGE) LATE  
TUESDAY INTO EARLY WEDNESDAY ACROSS SOUTHERN LOUISIANA, WITH A  
GREATER FOCUS FOR TRAINING CONVECTION NEAR LAKE CHARLES  
AROUND/AFTER 00Z. A SLIGHT RISK WAS CONSIDERED FOR THIS UPDATE, BUT  
CONCERNS ABOUT ANTECEDENT GROUND CONDITIONS (DRY SOILS, LACK OF  
RAINFALL) AND CONFIDENCE IN THE SPECIFIC AXES OF HEAVIER RAINFALL  
WERE MITIGATING FACTORS. THE MARGINAL RISK WAS EXPANDED  
NORTHWESTWARD TOWARD EAST TEXAS AND WEST/NORTHWEST LOUISIANA WHERE  
SOILS WERE WETTER AND CONVERGENCE ON THE NOSE OF 850MB FLOW COULD  
RESULT IN A FEW HEAVIER DOWNPOURS AND ISOLATED RUNOFF ISSUES.  
 
SEE THE PREVIOUS DISCUSSION BELOW FOR MORE INFORMATION.  
 
COOK  
   
..PREVIOUS DISCUSSION  
 
STRENGTHENING SOUTHWESTERLY WINDS AHEAD AN AMPLIFYING UPPER LEVEL  
SHORTWAVE AND AN ASSOCIATED COLD FRONT ARE EXPECTED TO DRAW DEEPER  
MOISTURE INTO PARTS OF THE GULF COAST, WITH PWS CLIMBING TO AROUND  
1.5 INCHES. THIS MOISTURE ALONG WITH INCREASING LIFT AND  
INSTABILITY MAY BE SUFFICIENT FOR HEAVY RAINFALL RATES. MODELS  
OFFER A MODEST SIGNAL FOR TRAINING STORMS AHEAD OF A SURFACE LOW  
THAT IS FORECAST TO DEVELOP AND ADVANCE EAST ALONG THE COAST  
WEDNESDAY MORNING. THIS MAY HELP SUPPORT LOCALIZED HEAVY RAINFALL,  
WITH SOME POTENTIAL FOR ISOLATED FLASH FLOODING, ESPECIALLY IN  
URBANIZED AREAS.  
 
PEREIRA  
 
DAY 3  
VALID 12Z WED FEB 19 2025 - 12Z THU FEB 20 2025  
 
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS  
OF NORTHERN FLORIDA AND SOUTHERN GEORGIA...  
   
..21Z OUTLOOK UPDATE  
 
A CONVECTIVE COMPLEX SHOULD BE ONGOING ACROSS SOUTHEASTERN  
LOUISIANA AND ADJACENT NORTH-CENTRAL GULF WATERS AT THE BEGINNING  
OF THE FORECAST PERIOD. THIS COMPLEX WILL MIGRATE EASTWARD TOWARD  
THE FLORIDA PANHANDLE AND VICINITY THROUGHOUT THE MORNING HOURS,  
ALTHOUGH HEAVIER RAINFALL SHOULD REMAIN OFFSHORE DUE TO A LACK OF  
INLAND INSTABILITY. LIGHT/MODEST RAIN RATES ARE EXPECTED ACROSS  
MOST OF THE SOUTHEASTERN U.S. DOWNSTREAM OF THE COMPLEX, AND MODELS  
HAVE TRENDED LOWER WITH QPF ESPECIALLY THROUGH NORTHEASTERN  
FLORIDA.  
 
GIVEN THE LATEST TRENDS, THE MARGINAL RISK PREVIOUSLY IN EFFECT HAS  
BEEN CONFINED TO AREAS FROM SOUTHEASTERN LOUISIANA THROUGH THE WESTERN  
FLORIDA PANHANDLE CLOSER TO WHERE THE BEST INSTABILITY SHOULD  
RESIDE.  
 
SEE THE PREVIOUS DISCUSSION FOR MORE INFORMATION.  
 
COOK  
   
..PREVIOUS DISCUSSION  
 
SURFACE LOW DEVELOPING ALONG THE CENTRAL GULF COAST ON DAY 2 WILL  
CONTINUE TO TRACK EAST EARLY IN THE PERIOD, BEFORE TRACKING  
NORTHEAST ALONG THE SOUTHEAST COAST LATER IN THE DAY. TRAINING  
STORMS, WITH POTENTIALLY HEAVY RAINFALL RATES FUELED BY DEEP  
MOISTURE (PWS 1.5-1.75 INCHES) AHEAD OF THE WAVE AND ALONG ITS  
TRAILING COLD FRONT, MAY PRODUCE LOCALLY HEAVY AMOUNTS AND AN  
ISOLATED FLASH FLOODING THREAT ON WEDNESDAY.  
 
PEREIRA  
 
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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