646  
FOUS30 KWBC 201808  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
108 PM EST TUE JAN 20 2026  
 
DAY 1  
VALID 16Z TUE JAN 20 2026 - 12Z WED JAN 21 2026  
 
TEXAS COAST...  
AN AREA OF MOISTURE CONVERGENCE/FRONTOGENESIS HAS BEEN THE FOCUS  
OF SHOWERS TRYING TO STREAM INTO THE MIDDLE TX COAST OFF THE GULF  
OF MEXICO. THE 0.5"+ AN HOUR RAIN AMOUNTS HAVE BEEN FOCUSED OFF THE  
COAST, ALONG THE LINES OF THE OUTPUT FROM THE 12Z HREF GUIDANCE.  
WITH TIME, THE RAP SHOWS THE FLOW VEERING IN THIS AREA, SHOWING  
LESS OF A SURFACE FOCUS FOR THE CONVECTION WITH TIME. THE 12Z HREF  
IS FOCUSING WHATEVER HEAVY RAIN THREAT THAT EXISTS JUST OFFSHORE OF  
PORT O'CONNOR, MOSTLY DURING THE 16-20Z TIME FRAME, BEFORE FADING.  
LOCAL TOTALS TO 3" ARE EXPECTED JUST OFFSHORE. EVEN IF THIS  
ACTIVITY WERE TO UNEXPECTEDLY DRIFT ASHORE, THE HEAVY RAINFALL RISK  
APPEARS TOO ISOLATED AND TOO LIMITED FOR A MARGINAL RISK AREA, SO  
LEFT THE GRAPHIC AREA-FREE.  
 
THE PROBABILITY OF RAINFALL EXCEEDING FLASH FLOOD GUIDANCE IS LESS  
THAN 5 PERCENT.  
 
ROTH  
 
DAY 2  
VALID 12Z WED JAN 21 2026 - 12Z THU JAN 22 2026  
 
SOUTH FLORIDA...  
THE BEST SIGNAL FOR HEAVY RAINFALL THIS PERIOD FOCUSES NEAR AN  
INVERTED TROUGH SHARPENING ALONG THE SOUTH FLORIDA COAST,  
AS PRECIPITABLE WATER VALUES RISE TO 1.5" AND INSTABILITY TRIES TO  
MOVE ASHORE FROM THE GULF STREAM. THE 12Z HREF/06Z REFS ADVERTISE  
0.5"+ AN HOUR AMOUNTS RIGHT AT THE END OF THE PERIOD THURSDAY  
MORNING, WITH A 40%+ CHANCE OF 2"+ SOMEWHERE BETWEEN COASTAL  
BROWARD AND MARTIN COUNTIES. AT THE MOMENT, THE THREAT OF FLASH  
FLOODING HERE APPEARS TOO ISOLATED AND TOO MARGINAL FOR A MARGINAL  
RISK TO BE DEPICTED.  
 
THE PROBABILITY OF RAINFALL EXCEEDING FLASH FLOOD GUIDANCE IS LESS  
THAN 5 PERCENT.  
 
ROTH  
 
DAY 3  
VALID 12Z THU JAN 22 2026 - 12Z FRI JAN 23 2026  
 
SOUTH FLORIDA...  
THE BEST SIGNAL REMAINS NEAR SOUTH FLORIDA THURSDAY MORNING WHERE  
ENOUGH MOISTURE AND INSTABILITY APPEAR TO EXIST FOR LOCALLY HEAVY  
RAIN. THE GUIDANCE APPEARS TO DRIFT THIS ACTIVITY NORTHWARD AS THE  
LOW- LEVEL FLOW VEERS; CONVECTION IS NOT EXPECTED TO SIT IN ANY  
PARTICULAR LOCATION FOR TOO LONG. AT THE MOMENT, THE THREAT OF  
FLASH FLOODING HERE APPEARS TOO ISOLATED/MARGINAL FOR A MARGINAL  
RISK TO BE DEPICTED.  
 
THE PROBABILITY OF RAINFALL EXCEEDING FLASH FLOOD GUIDANCE IS LESS  
THAN 5 PERCENT.  
 
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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