442  
FOUS30 KWBC 061559  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1159 AM EDT SAT JUN 6 2026  
 
DAY 1  
VALID 16Z SAT JUN 06 2026 - 12Z SUN JUN 07 2026  
 
...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE  
SOUTHERN PLAINS, OHIO VALLEY, UPPER TEXAS COAST, AND CENTRAL GULF  
COAST...  
   
..SOUTHERN PLAINS
 
 
A PLUME OF DEEP TROPICAL MOISTURE WILL SURGE NORTHWARD ACROSS THE  
SOUTHERN PLAINS SATURDAY. THE LOW LEVEL JET ADVECTING THIS MOISTURE  
NORTH WILL RUN INTO AN AREA OF ENHANCED LIFT DUE TO A NEARBY  
LINGERING UPPER-LOW, WHICH WILL BE LIFTING NORTHEAST TO REJOIN THE  
JET. THE RESULT WILL BE A SERIES OF ROUNDS OF STORMS MOVING NORTH-  
NORTHEAST ACROSS PORTIONS OF NORTH/NORTHWEST TEXAS, OKLAHOMA, AND  
WESTERN ARKANSAS. HIGHLY EFFICIENT WARM RAIN PROCESSES WILL  
DOMINATE DUE TO THE PRESENCE OF SUCH ABUNDANT AMOUNTS OF MOISTURE,  
WITH PWATS CLOSE TO 2 INCHES. FOR EASTERN OKLAHOMA/WESTERN  
ARKANSAS, RAINFALL IS ALREADY ONGOING AND WILL PERSIST FOR MUCH OF  
THE DAY IN THE FORM OF TRAINING LINES OF STORMS. TO THE WEST,  
ANOTHER ROUND OF STORMS IS EXPECTED TO DEVELOP WITH DAYTIME HEATING  
ALONG THE EASTERN PERIPHERY OF THE UPPER-LOW, WITH THE EXPECTATION  
THAT REPEATED ROUNDS OF STORM DEVELOPMENT AND STORM  
CLUSTERING/MERGING COLD POOLS MAY EVENTUALLY LEAD TO A MORE  
ORGANIZED CONVECTIVE SYSTEM THAT WILL PROGRESS SLOWLY TO THE EAST-  
SOUTHEAST THROUGH THE EVENING AND OVERNIGHT HOURS. AN INTERNAL  
HIGHER- END SLIGHT COVERS FROM SOUTHWEST OF THE METROPLEX THROUGH  
IT, AND CONTINUING INTO MUCH OF EASTERN OKLAHOMA AND WESTERN  
ARKANSAS FOR THE COMBINATION OF TWO AREAS OF PERSISTENT HEAVY RAIN.  
THE LATEST CONVECTION ALLOWING GUIDANCE (CAMS) SHOW PEAK RAIN  
RATES REACHING UPWARDS OF 2-3 INCHES PER HOUR WITH LOCALLY HEAVY  
TOTALS INTO THE 5-6+ INCH RANGE, MORE THAN SUFFICIENT FOR AT LEAST  
SCATTERED INSTANCES OF FLASH FLOODING DESPITE SOME LOCALLY DRIER  
ANTECEDENT CONDITIONS.  
 
   
..OHIO VALLEY
 
 
A VERY-SLOW MOVING COLD FRONT DRIFTING SOUTH ACROSS THE  
MIDWEST/OHIO VALLEY ON SATURDAY WILL BE THE ANIMUS FOR MULTIPLE  
ROUNDS OF STORMS WHICH WILL TRACK EAST-SOUTHEAST WITHIN THE SLIGHT  
RISK AREA ROUGHLY FROM CENTRAL INDIANA EAST TO THE CENTRAL  
APPALACHIANS. THE FRONT WILL FORM THE LEADING NOSE OF A PLUME OF  
DEEP GULF MOISTURE TRACKING NORTHWARD UP THE MISSISSIPPI VALLEY.  
THE FRONT WILL "SHEAR" THE MOISTURE EASTWARD IN A NARROW CORRIDOR,  
ALONG WHICH THE STORMS WILL FORM AND MOVE. THERE IS SOME  
UNCERTAINTY AS TO HOW PERSISTENT AN ONGOING COMPLEX OF STORMS  
MOVING INTO CENTRAL OHIO WILL BE AS THEY PROGRESS EAST-  
SOUTHEASTWARD THROUGH THE AFTERNOON. HOWEVER, EVEN IF STORMS DO NOT  
MAINTAIN QUITE THE SAME STRENGTH/ORGANIZATION AS THEY MOVE INTO  
THE MOUNTAINS OF WESTERN PENNSYLVANIA AND WEST VIRGINIA, THESE  
AREAS HAVE LOWER FFG THRESHOLDS AND THE RISK FOR SCATTERED FLASH  
FLOODING WILL REMAIN A CONCERN. UPLIFT ALONG THE WESTERN FACE OF  
THE APPALACHIANS MAY ALSO LOCALLY ENHANCE RAINFALL RATES. ANOTHER  
ROUND OF STORMS IS EXPECTED ALONG THE BOUNDARY FURTHER WEST WITHIN  
THE SLIGHT RISK OVER CENTRAL INDIANA WHERE THE CAMS/HREF SUGGEST  
HEAVIER TOTALS INTO THE 3-5 INCH RANGE ARE POSSIBLE. ADDITIONAL  
STORMS ARE ALSO FORECAST TO DEVELOP FURTHER WEST ALONG THE BOUNDARY  
STRETCHING THROUGH CENTRAL ILLINOIS AND ALONG THE IOWA/MISSOURI  
BORDER. HOWEVER, THESE STORMS ARE FORECAST TO REMAIN MORE  
SCATTERED/LESS ORGANIZED WITH GENERALLY LOWER RAIN TOTALS IN THE  
CAMS, KEEPING THE FLASH FLOOD THREAT MORE ISOLATED COMPARED TO  
FURTHER EAST.  
 
   
..UPPER TEXAS COAST
 
 
A SLIGHT RISK REMAINS IN EFFECT FOR THE GREATER HOUSTON AREA/UPPER  
TEXAS GULF COAST. EXTREME AMOUNTS OF MOISTURE WILL BE IN PLACE  
THROUGHOUT THE ATMOSPHERE OF SOUTHEAST TEXAS SATURDAY AFTERNOON.  
PWATS BETWEEN 2 AND 2.25 INCHES ARE 3 SIGMA ABOVE NORMAL FOR THIS  
TIME OF YEAR, AN IMPRESSIVE THRESHOLD TO MEET FOR JUNE. WITH PEAK  
HEATING THIS AFTERNOON, SCATTERED SHOWERS AND THUNDERSTORMS ARE  
EXPECTED TO FORM, LIKELY 20-50 MILES INLAND FROM THE COAST. COLD  
POOLS FROM FRIDAY'S STORMS AND NEW ONES FROM THE STORMS THAT FORM  
SATURDAY AFTERNOON WILL LIKELY DRIVE NEW STORM DEVELOPMENT ALONG  
THE I-10 CORRIDOR FROM SOUTHWEST OF HOUSTON EAST INTO SOUTHWESTERN  
LOUISIANA. WITH PLENTY OF NEW MOISTURE STREAMING NORTH OFF THE  
GULF, THE STORMS WILL HAVE NO TROUBLE REFORMING AND TRAINING OVER  
THE SAME AREAS FOR THE DURATION OF THE LONG AFTERNOON. NIGHTFALL  
SHOULD END THE STORMS IN THE AREA DUE TO LACK OF OTHER FORCING AND  
THE LOSS OF INSTABILITY. FRIDAY'S STORMS HAVE KNOCKED DOWN FFGS IN  
THIS REGION SIGNIFICANTLY, AND WITH GOOD CAPABILITY OF EFFICIENT  
WARM RAIN PROCESSES, URBAN CONCERNS IN HOUSTON, AND SLOW STORM  
MOVEMENT WERE ALL REASONS CONTRIBUTING TO THE SLIGHT RISK.  
 
   
..CENTRAL GULF COAST
 
 
NO CHANGES WERE NEEDED TO THE SLIGHT RISK AREA FROM NEW ORLEANS  
EAST TO PENSACOLA. A STRONG FRONT IS IN PLACE ACROSS THE EASTERN  
GULF, CHARACTERIZED BY VERY DRY AIR TO ITS EAST, RATHER THAN ANY  
SIGNIFICANT TEMPERATURE GRADIENT. THE DRY AIR IS 2 SIGMA BELOW  
NORMAL OVER PORTIONS OF CENTRAL FLORIDA...UNDER 1 INCH PWATS.  
MEANWHILE TO THE WEST FROM LOUISIANA THROUGH TEXAS, AN ABNORMALLY  
MOIST AIR MASS WILL BE STREAMING NORTH TO THE WEST OF THE HIGH  
PRESSURE AREA CHARACTERIZED BY THE DRY AIR. OVER MUCH OF LOUISIANA,  
PWATS WILL BE OVER 2.25 INCHES OR 3 SIGMA ABOVE NORMAL. THE FRONT  
MAKES UP THE GRADIENT BETWEEN THESE EXTREMELY CONTRASTING AIR  
MASSES. THROUGH THE DAY, THE FRONT WILL PUSH EAST AS THE MOIST AIR  
MASS GRADUALLY GAINS GROUND. HOWEVER, THE FRONT WILL BE THE FORCING  
ALONG WHICH NUMEROUS SHOWERS AND THUNDERSTORMS PUSHING NORTH OUT  
OF THE GULF WILL FORM ALONG. THE FRONT WILL BE SLOW TO MOVE,  
ALLOWING REPEATING ROUNDS OF STORMS TO IMPACT THE CENTRAL GULF  
COAST. FFGS ARE HIGH, ABOUT 4 INCHES/HOUR, BUT THE REPEATING ROUNDS  
OF STORMS SHOULD RATHER QUICKLY BRING THOSE NUMBERS DOWN, ALLOWING  
FOR SCATTERED INSTANCES OF FLASH FLOODING TO DEVELOP WHERE THE  
RAINS ARE MOST PERSISTENT BY LATE AFTERNOON, PARTICULARLY FOR URBAN  
AREAS. HREF PROBABILITIES FOR RAINFALL EXCEEDING 5 INCHES ARE ALSO  
MODERATE TO HIGH (45-70%), WITH LOW END PROBABILITIES (~15%) OF  
EXCEEDING 8 INCHES. STORMS ARE ALSO EXPECTED WEST ALONG AND JUST TO  
THE NORTH OF THE I-10 CORRIDOR BETWEEN THE SLIGHT RISKS COVERING  
SOUTHEASTERN AND FAR SOUTHWESTERN LOUISIANA. HOWEVER, MORE  
PERSISTENT FORCING/GREATER STORM COVERAGE TO THE EAST AND LOWER  
FFGS TO THE WEST SUGGEST THERE WILL BE A RELATIVELY MORE ISOLATED  
THREAT IN BETWEEN. SIMILAR TO THE UPPER TEXAS COAST, NIGHTFALL  
SHOULD SEE A DECREASE IN SHOWER AND STORM ACTIVITY, ENDING THE  
FLOODING THREAT.  
 
PUTNAM/WEGMAN  
 
DAY 2  
VALID 12Z SUN JUN 07 2026 - 12Z MON JUN 08 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE  
MID-MISSISSIPPI VALLEY, OZARKS, AND THE WESTERN TENNESSEE  
VALLEY...  
 
A PAIR OF FORCINGS WILL WORK CAUSE RENEWED ROUNDS OF SHOWERS AND  
STORMS ACROSS MUCH OF THE MISSISSIPPI VALLEY ON SUNDAY INTO SUNDAY  
NIGHT. A SLOW MOVING BUT STILL POTENT UPPER LEVEL LOW WILL TRACK  
NORTHEASTWARD UP THE PLAINS AND INTO THE MIDWEST BY LATE SUNDAY  
NIGHT. MEANWHILE A STRONG FRONT ORIENTED NORTH-SOUTH WILL ALLOW FOR  
SHOWER AND THUNDERSTORM DEVELOPMENT FURTHER EAST ACROSS PORTIONS OF  
THE SOUTH. FOR THE MID-MISSISSIPPI VALLEY AND OZARKS, THE SHORTWAVE  
WILL BE THE PRIMARY FORCING. DEEP TROPICAL MOISTURE CHARACTERIZED  
BY PWATS ON EITHER SIDE OF 2 INCHES WILL ADVECT NORTHWARD UP THE  
MISSISSIPPI VALLEY. THE SHORTWAVE WILL PROVIDE THE FORCING FOR  
STORMS TO FORM, ALONG WITH THE TOPOGRAPHY OF THE OZARKS. MANY OF  
THESE AREAS, ESPECIALLY FROM FAR EASTERN OKLAHOMA, NORTHWESTERN  
ARKANSAS, AND SOUTHWEST MISSOURI HAVE SEEN REPEATED ROUNDS OF HEAVY  
RAIN IN RECENT DAYS, SO FFGS ARE LOWER IN THIS AREA. THUS, A  
HIGHER-END SLIGHT WAS INTRODUCED FOR THIS AREA DEPICTING AN EVEN  
GREATER THREAT FOR FLASH FLOODING, AS THE TOPOGRAPHY OF THE OZARKS  
WORKS TO INCREASE THE SEVERITY OF ANY FLOODING. FFGS ARE ALSO LOWER  
FROM NORTHERN MISSOURI INTO IOWA. STORMS FORMING IN THESE AREAS  
WILL BE CLOSER TO THE NOSE OF THE LOW LEVEL JET, THOUGH THE UPPER  
LEVEL SHORTWAVE SHOULD STILL BE THE PRIMARY FORCING.  
 
THE SLIGHT RISK AREA WAS EXPANDED NORTH UP THE MISSISSIPPI VALLEY  
INTO SOUTHERN AND EASTERN IOWA AND WESTERN ILLINOIS WITH THIS  
UPDATE.  
 
FOR PORTIONS OF THE WESTERN TENNESSEE VALLEY, INCLUDING WESTERN  
TENNESSEE FAR NORTHEASTERN MISSISSIPPI, AND ESPECIALLY NORTHERN  
ALABAMA, THE AFOREMENTIONED NORTH-SOUTH ORIENTED FRONT WILL BE THE  
PRIMARY FORCING FOR THE FIRST HALF OF THE DAY. THE FRONT WILL MORE  
RAPIDLY RETREAT EAST ACROSS GEORGIA BY SUNDAY NIGHT, LEAVING ANY  
FORCING TO WEAK UPPER LEVEL SHORTWAVES. THUS, MOST OF THE STORMS  
WILL BE DURING THE AFTERNOON AND EVENING DURING PEAK HEATING AND  
WHEN THE FRONT IS CLOSER. FFGS ARE LOWER ACROSS NORTHERN ALABAMA  
FROM RECENT HEAVY RAINFALL, AROUND 2.5 IN/HOUR, WHICH DUE TO PWATS  
OCCASIONALLY OVER 2 INCHES, SHOULD BE EASILY ATTAINABLE BY THE  
STRONGEST STORMS EXPECTED SUNDAY AFTERNOON. THUS, THE SLIGHT RISK  
WAS EXPANDED SOUTHEAST FOR THESE REASONS.  
 
WEGMAN  
 
DAY 3  
VALID 12Z MON JUN 08 2026 - 12Z TUE JUN 09 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE  
MID-MISSISSIPPI, LOWER OHIO, AND WESTERN TENNESSEE VALLEYS...  
 
ON MONDAY, THE EXCESSIVE RAINFALL RISK TRANSLATES A BIT FURTHER  
NORTH AND EAST INTO THE MID-MISSISSIPPI, LOWER OHIO, AND WESTERN  
TENNESSEE VALLEYS. A STRONG FRONT OVER THE GREAT LAKES WILL RETREAT  
NORTHEASTWARD AS THE PLUME OF ANOMALOUSLY DEEP MOISTURE FROM THE  
GULF SURGES NORTHEASTWARD TO REPLACE THE DRIER AIR MASS IN PLACE  
OVER THE NORTHEAST. A SLOW-MOVING NEGATIVELY TILTED TROUGH WILL  
ALSO PROMOTE UPPER DIVERGENCE AND LIFT THROUGHOUT THE ATMOSPHERE  
OVER THE SLIGHT RISK AREA THROUGHOUT THE PERIOD. PWATS AROUND 2  
INCHES WILL BE 3 SIGMA ABOVE NORMAL FOR THIS TIME OF YEAR ACROSS  
THE REGION, SO MANY OF THE STORMS THAT FORM WILL CONSIST OF HIGHLY  
EFFICIENT WARM RAIN PROCESSES, WHICH WILL PROMOTE HEAVY RAINFALL.  
FFGS ACROSS THE REGION WILL AVERAGE AROUND 2-2.5 INCHES, WHICH WILL  
BE EASILY OVERCOME BY MANY OF THE STRONGEST CELLS, SO LONG AS THEIR  
FORWARD SPEED IS KEPT IN CHECK. THE SLIGHT RISK AREA WAS NUDGED  
WEST OVER MORE OF SOUTHEASTERN MISSOURI WITH THIS UPDATE, ADJUSTED  
FOR EXPECTED HEAVY RAINFALL AND LIKELY LOWER FFGS IN THIS REGION  
FROM THE DAY 2/SUNDAY PERIOD.  
 
WEGMAN  
 
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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