588  
FOUS30 KWBC 140826  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
426 AM EDT TUE APR 14 2026  
 
DAY 1  
VALID 12Z TUE APR 14 2026 - 12Z WED APR 15 2026  
 
...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS THE CENTRAL  
L.P. OF MICHIGAN AND SOUTHEAST WISCONSIN...  
   
..GREAT LAKES REGION
 
 
A SLIGHT RISK FOR EXCESSIVE RAINFALL REMAINS IN EFFECT FOR PORTIONS  
OF THE GREAT LAKES REGION. A SHORTWAVE/VORTICITY CENTER LIFTING  
OUT OVER THE MEAN RIDGE IN THE GREAT LAKES REGION WILL DRIVE  
STRONGER CONFLUENCE OF THE LOW LEVEL JET ACROSS IOWA TO TRIGGER ANOTHER  
ROUND OF STRONG TO SEVERE THUNDERSTORMS TUESDAY EVENING. OVERALL  
DEEP LAYER STEERING FLOW AND FAIRLY ORTHOGONAL ASCENT OVER BOUNDARY  
SHOULD HELP TO FOCUS A SIMILAR WEST TO EAST (WNW TO ENE) ORIENTED  
AXIS OF TRAINING THUNDERSTORMS. UPPER-LEVEL DUAL JET COUPLET WILL  
FURTHER ENHANCE UP-SCALE GROWTH TO A BROADER COMPLEX TO MAINTAIN  
THROUGH THE OVERNIGHT PERIOD. MOST OF THE AREA REMAINS AT NEAR OR  
ABOVE RECORD SPRING RAINFALL AND SOILS ARE FAIRLY SATURATED, SO  
WITH CELLS CAPABLE OF 1.5-2"/HR RATES AND LOCALIZED TOTALS OF 2-3+"  
SUGGEST THE PLACEMENT OF A SLIGHT RISK OF EXCESSIVE RAINFALL  
ACROSS PORTIONS OF EASTERN WI AND CENTRAL MI (ALONG AND NORTH OF  
I-94).  
   
..PECOS RIVER VALLEY THROUGH SOUTHERN PLAINS INTO OZARK PLATEAU
 
 
A STEADY STREAM OF PW VALUES OF 1.25 TO 1.5 INCHES WILL BE  
ADVECTING NORTHWARD THROUGH THE SOUTHERN/CENTRAL PLAINS NEARLY  
PARALLEL TO THE DRYLINE. THIS WILL BE CONDUCIVE FOR SLOW STORM  
MOTION WITH LOCALLY HEAVY RAINFALL. CONSENSUS SUGGESTS 3 TO 4  
INCHES POSSIBLE WITHIN THE ISOLATED CELLS. THE MARGINAL RISK AREA  
IS CONNECTED TO THE AREA OF CONCERN OVER THE GREAT LAKES AND JUST  
NOTE THE COVERAGE WILL DECREASE NORTHWARD ALONG THE DRY-LINE.  
 
CAMPBELL/GALLINA  
 
DAY 2  
VALID 12Z WED APR 15 2026 - 12Z THU APR 16 2026  
 
...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM TEXAS TO  
THE UPPER MIDWEST/GREAT LAKES REGION...  
 
THE SURFACE TO MID-LEVEL ENVIRONMENT REMAINS VERY SIMILAR TO THE  
PRIOR 3 DAYS, WITH A STARK DRY LINE EXTENDING FROM THE PECOS RIVER  
VALLEY ACROSS THE SOUTHERN PLAINS INTO THE UPPER MISSISSIPPI  
VALLEY. DURING THIS PERIOD THE LONGWAVE TROUGH WILL FINALLY BE  
MAKING PROGRESS TOWARD THE CENTRAL PLAINS ALBEIT AS IT BEGINS TO  
WEAKEN AND THE DEEP LAYER MOISTURE AXIS AND INSTABILITY SHIFT  
SLIGHTLY EASTWARD. THUNDERSTORMS ARE EXPECTED TO BREAK OUT WITH  
HOURLY RATES PULSING UP TO 2 INCHES/HR. SOME LOCATIONS AHEAD OR  
ALONG THE FRONTAL BOUNDARY MAY RECEIVE OVER 3 INCHES BETWEEN THE  
OZARKS PLATEAU AND NORTHEAST TEXAS.  
 
FURTHER NORTH, THE ENVIRONMENT OVER THE MIDWEST/GREAT LAKES REGION  
WILL HAVE NOTABLY LESS MOISTURE AND INSTABILITY PRESENT THEN THE  
DAYS PRIOR, HOWEVER ADDITIONAL RAINS WILL MAINTAIN AN ELEVATED  
THREAT FOR LOCALIZED FLOODING OVER THE HYDROLOGICALLY  
SENSITIVE/SATURATED AREAS OF THE NORTHERN GREAT LAKES REGION. THE  
MOST FAVORABLE LOCATION FOR APPRECIABLE PRECIPITATION WILL BE FROM  
NORTHEAST ILLINOIS TO SOUTHER MICHIGAN. THE MARGINAL RISK AREA WAS  
MAINTAINED AND IN SPANS FROM NORTHEAST TEXAS NORTHWARD TO  
WISCONSIN/LOWER MICHIGAN AND EAST TO WESTERN NEW YORKS AND  
PENNSYLVANIA.  
 
CAMPBELL/GALLINA  
 
DAY 3  
VALID 12Z THU APR 16 2026 - 12Z FRI APR 17 2026  
 
THE PROBABILITY OF RAINFALL EXCEEDING FLASH FLOODING GUIDANCE IS  
LESS THAN 5 PERCENT.  
 
CAMPBELL  
 
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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