270  
FOUS30 KWBC 141605  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1205 PM EDT TUE APR 14 2026  
 
DAY 1  
VALID 16Z TUE APR 14 2026 - 12Z WED APR 15 2026  
 
...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS THE CENTRAL  
L.P. OF MICHIGAN,SOUTHEAST WISCONSIN, AND THE OHIO VALLEY...  
   
.. OHIO VALLEY
 
 
16Z UPDATE: THE SLIGHT RISK FOR EXCESSIVE RAINFALL WAS EXPANDED  
FARTHER SOUTH TO INCLUDE CENTRAL ILLINOIS TO CENTRAL INDIANA.RADAR  
AND SURFACE OBSERVATIONS SHOW AN OUTFLOW BOUNDARY LINGERING ACROSS  
THE REGION FROM EARLY MORNING SHOWERS AND THUNDERSTORMS THAT MAY BE  
A FOCAL POINT FOR LOCALLY HEAVY RAINFALL THIS AFTERNOON AND  
EVENING. THE RRFS AND ARW MODEL CAMPS IN PARTICULAR ARE  
HIGHLIGHTING THIS REGION WITH QPF MAXIMA IN THE 2-5 INCH RANGE.  
HIGH SEASONABLE PWATS AND ABUNDANT INSTABILITY ALSO SUPPORT THE  
POTENTIAL FOR HIGH HOURLY RAINFALL RATES.  
   
..WISCONSIN AND MICHIGAN
 
 
16Z UPDATE:  
 
THE FORECAST CONTINUES TO SUPPORT THE RISK FOR FLASH  
FLOODING AS STORMS ARE EXPECTED TO FORM ALONG A STATIONARY BOUNDARY  
OVER WISCONSIN AND THEN CONGEAL INTO A LINE OF STORMS THAT  
PROGRESSES SOUTHEASTWARD INTO MICHIGAN. THE LOW LEVEL JET WILL  
TRANSPORT MOISTURE ORTHOGONAL TO A STATIONARY BOUNDARY ACROSS THE  
REGION WITH THE TRAINING OF STORMS POSSIBLE. MOST OF THE AREA  
REMAINS AT NEAR OR ABOVE RECORD SPRING RAINFALL AND SOILS ARE  
FAIRLY SATURATED. CELLS CAPABLE OF 1.5-2"/HR RATES AND LOCALIZED  
TOTALS OF 2-3+" SUGGEST THE PLACEMENT OF A SLIGHT RISK OF EXCESSIVE  
RAINFALL FROM SOUTHERN WISCONSIN TO EASTERN MICHIGAN.  
   
..PREVIOUS DISCUSSION
 
 
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).  
   
.. LOWER TRANS-PECOS/BIG BEND
 
 
16 UPDATE:  
 
LATEST MODEL GUIDANCE INDICATES A HIGHER QPF MAXIMA ACROSS THE  
LOWER TRANS-PECOS REGION INTO THE BIG BEND AS STORMS FIRE ALONG THE  
DRY LINE IN PRESENCE OF A SEASONALLY MOIST ENVIRONMENT. HREF 24  
HOUR QPF NEIGHBORHOOD PROBABILITIES ARE AROUND 50-70% FOR 2 INCHES  
AND 10-20% PROBABILITIES FOR 3 HOUR QPF EXCEEDING FLASH FLOOD  
GUIDANCE. A MARGINAL RISK WAS MAINTAINED, BUT THIS AREA WILL BE A  
FOCUS FOR LOCALLY HEAVY RAINFALL.  
   
..OKLAHOMA AND KANSAS
 
 
16Z UPDATE: ANOTHER TARGETED AREA FOR HEAVY RAINFALL WILL BE SPAN  
SOUTH OF THE NORMAN AREA, NORTHEASTWARD INTO THE TULSA METRO AND  
SOUTHERN KANSAS. HI-RES GUIDANCE INDICATES MULTIPLE ROUNDS OF  
STORMS COULD TRAVERSE THIS REGION AS STORMS FIRE ALONG THE DRY LINE  
BOUNDARY AND SOUTH OF A STATIONARY FRONT IN KANSAS. HREF 24 HOUR  
QPF PROBABILITIES EXCEEDING 2 INCHES ARE FAIRLY HIGH (50-70%) AND  
20-40% FOR EXCEEDING 3 INCHES.  
   
..PREVIOUS DISCUSSION
 
 
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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