416  
FOUS30 KWBC 160821  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
421 AM EDT TUE JUN 16 2026  
 
DAY 1  
VALID 12Z TUE JUN 16 2026 - 12Z WED JUN 17 2026  
 
...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
THE TEXAS GULF COAST THROUGH THE LOWER MISSISSIPPI VALLEY...  
 
AN IMPRESSIVE AND DYNAMIC SETUP WITH MULTIPLE MESOSCALE FEATURES  
IS EXPECTED TO DEVELOP THROUGH THE DAY TODAY FROM THE TEXAS GULF  
COAST THROUGH THE LOWER MISSISSIPPI VALLEY. THE MOST RAINFALL FOR  
THE DAY WILL OCCUR THROUGH THIS MORNING. A TROPICAL DISTURBANCE  
OVER DEEP SOUTH TEXAS WILL SUPPORT THE STRENGTHENING OF THE TYPICAL  
DIURNAL LOW LEVEL JET OUT OVER THE GULF, DRIVING A PLUME OF  
IMPRESSIVELY DEEP TROPICAL MOISTURE NORTHWARD INTO THE TEXAS AND  
LOUISIANA GULF COASTS. MEANWHILE A STATIONARY FRONT CURRENTLY OVER  
SOUTHERN ARKANSAS AND NORTHERN MISSISSIPPI WILL ADVANCE SOUTHWARD  
AS A COLD FRONT DUE TO A DISTURBANCE AND PUSH OF COOLER DRIER AIR  
SOUTH BEHIND THE FRONT. THIS CLASH OF AIR MASSES WILL RESULT IN  
CONTINUED UPSCALE DEVELOPMENT OF STORMS THAT HAVE BROKEN OUT OVER  
NORTHERN LOUISIANA THROUGH THE OVERNIGHT AND INTO TUESDAY MORNING.  
FFGS ARE ALREADY LOWER IN MANY SPOTS WEST FROM THE WESTERN TIP OF  
MISSISSIPPI. THIS NEARLY STATIONARY LINE OF TRAINING STORMS IS  
LIKELY TO PERSIST WELL INTO THE AFTERNOON, WHICH COULD MAKE FOR A  
NARROW BUT NEVERTHELESS SEVERE AREA OF VERY HIGH TOTALS OF STORM  
TOTAL RAINFALL, ESPECIALLY INTO WESTERN MISSISSIPPI. GUIDANCE HAS  
SUGGESTED THIS NARROW CORRIDOR, HIGHLIGHTED IN MUCH OF THE GUIDANCE  
SINCE YESTERDAY ALONG THE I-20 CORRIDOR HAS NOW SHIFTED A FEW  
COUNTIES SOUTH, EXTENDING FROM ALEXANDRIA, LA EAST ALMOST TO  
HATTIESBURG, MS. THE INHERITED MODERATE RISK FOR THIS AREA WAS  
TRIMMED ON THE NORTH SIDE BOTH WITH THE CURRENT START OF CONVECTION  
IN THIS CORRIDOR AND THE SOUTHWARD TREND IN THE GUIDANCE.  
 
MEANWHILE, A NUMBER OF OTHER PIECES OF CAMS GUIDANCE SUGGEST THAT  
THE SHOWERS AND STORMS DEVELOPING ALONG THE IMMEDIATE COAST ROUGHLY  
FROM GALVESTON/TRINITY BAYS EAST TO LAFAYETTE, LA WILL BE THE  
PRIMARY AND DOMINANT LINE OF SHOWERS AND STORMS IMPACTING THE  
NORTHWESTERN GULF COAST TODAY. THIS LINE WOULD FROM LARGELY FROM  
SEA BREEZE/FRICTIONAL CONVERGENCE OF THE STRONG ONSHORE SOUTHERLY  
FLOW INTO THE COAST. THE FRONT TO THE NORTH MAY PLAY A ROLE IN  
MAINTAINING THE STORMS WHERE THEY ARE, BUT WOULD LIKELY PLAY A  
SECONDARY ROLE. SHOULD THIS LINE DEVELOP ROBUSTLY, IT WILL FORCE  
THE AFOREMENTIONED LINE OF STORMS OVER NORTHERN LA/SOUTHWEST MS  
EASTWARD, RESULTING IN LESS RAIN OVER NORTHERN/CENTRAL LA. MOST  
LIKELY THERE WILL BE A COMBINATION OF THE TWO, WITH THE EAST-  
NORTHEASTWARD MOVING STORMS ALONG THE SOUTHWEST LOUISIANA COAST  
CONTINUING WITH THE LINE TO THE NORTHEAST OVER WESTERN MISSISSIPPI.  
ONCE AGAIN THE MODERATE RISK HERE REMAINS IN PLACE WITH FEW  
CHANGES.  
 
FINALLY, FURTHER SOUTH ALONG THE TEXAS GULF COAST, THE LARGER  
SYNOPTIC LEVEL DISTURBANCE, RESPONSIBLE FOR THE HEAVY RAINS AND  
FLASH FLOODING OVER DEEP SOUTH TEXAS YESTERDAY WILL LIKELY EJECT  
EAST INTO THE GULF TODAY. AS IT DOES SO, IT WILL CREATE LOCALIZED  
BANDS OF HEAVY RAIN ALONG THE MIDDLE TEXAS COAST, WHICH WILL THEN  
ADVECT NORTHEAST TO JOIN THE LINE EAST OF HOUSTON. THIS AREA FROM  
CORPUS CHRISTI TO HOUSTON REMAINS THE MOST UNCERTAIN PORTION OF THE  
MODERATE RISK AREA, AS A SMALL SOUTH/EAST SHIFT IN THE TRACK OF THE  
DISTURBANCE WILL TAKE THE LION'S SHARE OF THE ASSOCIATED RAINFALL  
AHEAD OF THE LOW TRACK OUT OVER THE OPEN GULF, AND GREATLY LIMIT  
ANY RAINFALL TODAY ALONG THE COAST. THE INHERITED MODERATE RISK WAS  
TRIMMED COMPLETELY SOUTH OF CORPUS CHRISTI, WITH JUST A SLIGHT  
ALONG THE IMMEDIATE LOWER TEXAS GULF COAST TO ACCOUNT FOR ONGOING  
RAINS IN THE AREA. THE THREAT WILL SHIFT OFF THE COAST BY LATE THIS  
AFTERNOON.  
 
WITH ALL THREE AREAS OF HEAVY RAIN ABOVE, THEY WILL ALL DIMINISH  
AND DISSIPATE AS A SIGNIFICANT HEAVY RAIN THREAT BY THIS EVENING.  
OCCASIONAL SHOWERS AND A STORM OR TWO MAY IMPACT THE IMMEDIATE GULF  
COAST THROUGH THE OVERNIGHT, BUT FOR THE MOST PART THE HEAVY RAIN  
THREAT THROUGH TONIGHT SHOULD BE MINIMAL.  
 
WEGMAN  
 
 
DAY 2  
VALID 12Z WED JUN 17 2026 - 12Z THU JUN 18 2026  
 
...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE UPPER  
TEXAS GULF COAST THROUGH SOUTHWESTERN LOUISIANA...  
   
..GULF COAST
 
 
AN UPPER LEVEL SHORTWAVE DISTURBANCE OVER THE NORTHWESTERN GULF  
WILL LIKELY CONTRIBUTE TO THE DEVELOPMENT OF A SMALL SURFACE LOW  
OR SURFACE TROUGH ALONG THE TEXAS GULF COAST ON WEDNESDAY. THIS  
DISTURBANCE WILL GRADUALLY TRACK PARALLEL TO THE COAST TOWARDS THE  
NORTHEAST, AND MOVE INTO SOUTHWESTERN LOUISIANA THIS EVENING. THE  
EXACT TRACK OF THE CENTER OF CIRCULATION WILL REMAIN THE  
DISTINCTIVE FACTOR DETERMINING HOW MUCH RAIN PENETRATES INLAND  
ALONG THE TEXAS COAST, INCLUDING INTO THE HOUSTON METRO. SOME OF  
THE CAMS GUIDANCE HAS TRENDED WEST WITH THE TRACK OF THE LOW, WHICH  
WILL PROLONG A PERIOD OF HEAVY RAIN INTO HOUSTON AS CELLS RIDE  
NORTHWESTWARD AHEAD OF THE LOW IN A SMALL BUT VERY POTENT BAND OF  
HEAVY RAIN. IT WILL BE POTENT NOT JUST BECAUSE OF THE MULTIPLE  
SOURCES OF FORCING FOR THE HEAVY RAIN, BUT ALSO THE SHEER AMOUNT OF  
ATMOSPHERIC MOISTURE THAT WILL BE AVAILABLE FOR THE STORMS TO TAP  
INTO. PWATS WILL REMAIN EXCEPTIONALLY HIGH, LIKELY PEAKING IN THE  
UPPER 2S AS THE LOW REACHES ITS PEAK INTENSITY THIS AFTERNOON.  
WHILE THE PREDOMINANT SOUTHERLY FLOW WILL ADVECT SOME INSTABILITY  
INTO THE LOW, EXTENSIVE CLOUD COVER WILL WORK AGAINST ACHIEVING  
HEAVY RAINFALL RATES IN MANY CASES. THE HYDROLOGY WILL BECOME  
INCREASINGLY FAVORABLE FOR FLASH FLOODING EVEN WITH LESS THAN  
OPTIMAL RAINFALL RATES AS PRIOR DAYS' RAINS COMBINE WITH THE NEW  
RAINFALL TO CONTINUE LOWERING FFGS. THE MODERATE RISK WAS NUDGED  
WEST IN COORDINATION WITH HGX/HOUSTON, TX FORECAST OFFICE TO  
INCLUDE ALL OF THE HOUSTON METRO. PROLONGED NORTHWESTWARD MOVING  
CELLS IN A NARROW BAND COULD EASILY START CAUSING FLASH FLOODING  
PROBLEMS OVER THE HOUSTON METRO SHOULD THE TRACK OPTIMIZE.  
 
FURTHER EAST, THERE IS MORE CERTAINTY WITH HEAVY RAINFALL RATES  
IMPACTING THE AREA FROM BEAUMONT EAST INTO SOUTHWESTERN LOUISIANA.  
SOUTHERLY FLOW EXACTLY ORTHOGONAL TO THE COAST, FRICTIONAL  
CONVERGENCE, AND THEN THE LOW ITSELF IMPACTING THE AREA FROM LATE  
IN THE DAY WEDNESDAY THROUGH WEDNESDAY NIGHT WILL ALL CONTRIBUTE TO  
ADDITIONAL HEAVY RAINS OVER AN AREA OF LOUISIANA ALREADY HARD HIT  
FROM THE CURRENT RAIN AND EXPECTED RAIN IN THE AREA ON DAY 1. THE  
MODERATE RISK AREA WAS LITTLE CHANGED FROM INHERITED IN THIS AREA.  
 
FURTHER NORTH AND EAST, THE HEAVY RAIN THREAT WILL CONCENTRATE OVER  
THE WEDNESDAY NIGHT TIMEFRAME. AS THE LOW AND ASSOCIATED UPPER  
LEVEL DISTURBANCE MOVE INTO LOUISIANA, A LEADING BAND OF HEAVY  
RAIN, ORIENTED SOUTHWEST TO NORTHEAST, WILL OVERSPREAD PORTIONS OF  
CENTRAL AND EASTERN LOUISIANA AND CONTINUE INTO WESTERN  
MISSISSIPPI. THERE IS CONSIDERABLE UNCERTAINTY HOW FAR INTO  
MISSISSIPPI THE HEAVY RAIN GETS. BUT IT WILL LIKELY EXTEND FROM THE  
COAST SOUTH OF LAFAYETTE NORTHEAST THROUGH BATON ROUGE AND INTO  
SOUTHWESTERN MISSISSIPPI. HERE TOO, FAVORABLE HYDROLOGY DUE TO WET  
SOILS FROM HEAVY RAINS FROM TODAY/DAY 1 WILL CONTRIBUTE TO ANY  
RESULTANT FLASH FLOODING. FOR NOW, THIS APPEARS TO STAY WEST OF NEW  
ORLEANS, BUT WILL LIKELY BE TOO CLOSE FOR COMFORT, AND THE NEW  
ORLEANS METRO COULD SEE OCCASIONAL HEAVY RAIN FROM PASSING CELLS.  
   
..MIDWEST
 
 
VERY FEW CHANGES WERE NEEDED TO THE LARGE SLIGHT RISK ACROSS MUCH  
OF THE MIDWEST ON WEDNESDAY. A STRONG AND IMPRESSIVELY POTENT LOW  
DRIVING EASTWARD FROM THE PLAINS WILL RUN INTO INCREASING AMOUNTS  
OF DEEP TROPICAL MOISTURE AS IT MOVES INTO THE GREAT LAKES. THIS  
WILL CONTRIBUTE TO INCREASING COVERAGE OF SHOWERS AND STORMS, FIRST  
WITH ITS WARM FRONT FROM CHICAGO EAST ALONG MICHIGAN'S SOUTHERN  
BORDER, THEN FOLLOWED VERY QUICKLY IN SOME AREAS BY STRONGER STORMS  
ASSOCIATED WITH THE LOW'S COLD FRONT. FAVORABLE HYDROLOGY FROM  
SEVERAL BOUTS OF HEAVY RAIN OVER THE PAST WEEK WILL SUPPORT FLASH  
FLOODING DEVELOPMENT. HOWEVER, THIS LOW AND ITS ASSOCIATED STORMS  
WILL BE RACING EASTWARD. THUS, DURATION OF HEAVY RAIN WILL BE VERY  
LIMITING IN MANY AREAS. FOR THE CORRIDOR FORMING THE NORTHERN HALF  
OF THE SLIGHT RISK AREA, HEAVY RAIN DURATION WILL BE LONGER, AS THE  
WARM FRONT AND ASSOCIATED ELEVATED CONVECTION QUICKLY FOLLOWED BY  
STRONGER CONVECTION WITH THE COLD FRONT COULD ALLOW FOR SOME AREAS  
TO SEE MULTIPLE HOURS WITH INTERSPERSED HEAVY RAIN THROUGH THE DAY.  
INSTABILITY MAY BE MORE LIMITED IN THIS AREA HOWEVER, SO THAT WILL  
WORK AGAINST HEAVY RAINS.  
 
FOR THE SOUTHERN HALF OF THE SLIGHT, THERE WILL BE SIGNIFICANTLY  
MORE MOISTURE AND INSTABILITY FOR THE STORMS TO WORK WITH AS THEY  
RACE SOUTHEASTWARD, SO RAINFALL RATES SHOULD BE HIGHER THAN FURTHER  
NORTH. HOWEVER, IT'S LIKELY JUST THE COLD FRONT'S STORMS THAT WILL  
IMPACT MOST AREAS, SO IT'S ONE SHOT AND DONE. TRAINING AND  
BACKBUILDING WON'T BE A CONCERN UNTIL YOU GET BACK INTO MISSOURI  
AND KANSAS. ONCE AGAIN, THE SOILS REMAIN WET IN THESE AREAS, SO IT  
MAY BE ENOUGH TO GET WIDELY SCATTERED INSTANCES OF FLASH FLOODING,  
PARTICULARLY IN URBAN AREAS. AS IS TYPICAL THIS TIME OF YEAR, THE  
COLD FRONT WILL HANG UP ON ITS SOUTHERN AND WESTERN PERIPHERY, AS  
IT RUNS INTO THE SOUTHWESTERLY LOW LEVEL JET. THIS WILL GREATLY  
EXTEND THE POTENTIAL FOR HEAVY RAIN FROM SOUTHEASTERN KANSAS  
THROUGH SOUTHERN MISSOURI WEDNESDAY NIGHT. THESE AREAS HAVE ALSO  
BEEN HARD HIT WITH HEAVY RAIN IN RECENT DAYS, AS WELL AS THE  
TOPOGRAPHY OF THE OZARKS, SO THE SLIGHT REMAINS IN PLACE THERE WITH  
FEW CHANGES.  
 
WEGMAN  
 
 
DAY 3  
VALID 12Z THU JUN 18 2026 - 12Z FRI JUN 19 2026  
 
...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
THE LOWER MISSISSIPPI VALLEY THROUGH CENTRAL ALABAMA...  
   
..LOWER MISSISSIPPI VALLEY THROUGH CENTRAL ALABAMA
 
 
THE TROPICAL LOW AND ITS ASSOCIATED MOISTURE ARE EXPECTED TO START  
THE DAY 3 PERIOD OVER NORTHERN LOUISIANA OR WESTERN MISSISSIPPI.  
THE LEADING BAND OF HEAVY RAIN WILL BE ONGOING FROM EASTERN  
LOUISIANA INTO SOUTHERN MISSISSIPPI. THE LOW WILL SLOWLY DRIFT  
EASTWARD ACROSS MISSISSIPPI THROUGH THE DAY, THEN GRADUALLY  
INCREASE ITS FORWARD SPEED THURSDAY NIGHT AS IT TRACKS EAST ACROSS  
ALABAMA AND ENDS THE PERIOD IN NORTHERN GEORGIA. A VERY PERSISTENT  
HEAVY BAND OF RAIN WILL REMAIN SOUTH AND EAST OF THE LOW CENTER  
THROUGHOUT THE DAY 3 PERIOD. THIS WILL FOCUS THE HEAVIEST RAINS IN  
THE MODERATE RISK CORRIDOR FROM CENTRAL LOUISIANA THROUGH CENTRAL  
ALABAMA. PROLONGED SOUTHERLY FLOW OF THE DEEP TROPICAL MOISTURE  
WITH PWATS TO 2.5 INCHES WILL SUPPORT DEVELOPMENT AND REDEVELOPMENT  
OF CONVECTION AHEAD OF THE MAIN BAND ASSOCIATED WITH THE LOW. THUS,  
HEAVY RAIN WITH MULTIPLE INCHES OF RAIN PER HOUR RAIN RATES ARE  
EXPECTED THROUGH THE MODERATE RISK AREA. SOILS IN LOUISIANA AND  
MISSISSIPPI ARE ALREADY SATURATED NOW EVEN BEFORE DAYS 1 AND 2'S  
RAINS. WHILE SOME PARTS OF CENTRAL ALABAMA HAVE DRY SOILS, THAT  
SHOULD CHANGE AS THE SOILS ARE PRIMED TODAY/DAY 1. THUS, BY DAY 3,  
THE ENTIRE MODERATE RISK AREA SHOULD HAVE WELL WETTER THAN NORMAL  
SOILS. THUS, HYDROLOGY WILL PLAY A BIG ROLE IN FLASH FLOOD  
DEVELOPMENT. FOR WESTERN AREAS, NEARLY CONSTANT HEAVY RAIN IN DAYS  
1-2 WILL MAKE FLOODING INTO D3/THURSDAY VERY EASY. FURTHER EAST  
INTO ALABAMA, THE SOUTHERLY FLOW OF DEEP TROPICAL MOISTURE WILL  
LAST LONGER AS THE LOW TRACKS EASTWARD, SO THERE WILL BE A LONGER  
PERIOD WHERE HEAVY RAIN MAY BE OCCURRING OVER ALABAMA. IN  
COORDINATION WITH BMX/BIRMINGHAM, AL FORECAST OFFICE, THE MODERATE  
RISK WAS EXPANDED EAST ACROSS CENTRAL ALABAMA WITH THIS UPDATE.  
EVEN ONCE THE LOW CENTER PASSES, THE AIR MASS WILL BE LARGELY  
UNCHANGED BEHIND THE LOW, AS THE TROPICAL AIR MASS WILL STILL BE IN  
PLACE INTO THE LOWER MISSISSIPPI VALLEY, THUS, THE LOW'S COLD FRONT  
COULD CONTINUE TO PRODUCE STORMS INTO SOUTHERN ALABAMA INTO  
THURSDAY NIGHT.  
   
..OHIO VALLEY
 
 
THE NORTHERN EDGE OF THE DEEP TROPICAL AIR MASS SUPPORTING THE  
TROPICAL LOW TO THE SOUTH WILL BUMP UP AGAINST A STRONG COLD FRONT  
THAT WILL BE SET UP ALONG THE OHIO RIVER ON THURSDAY. AS THE  
PLENTIFUL MOISTURE ON SOUTHWESTERLY FLOW RUNS INTO THE FRONT,  
TRAINING THUNDERSTORMS ARE EXPECTED THROUGH MUCH OF KENTUCKY,  
PARTICULARLY THE SOUTHERN HALF, THURSDAY AFTERNOON AND EVENING.  
THIS COULD LEAD TO A PROLONGED PERIOD OF HEAVY RAIN DUE TO TRAINING  
AND BACKBUILDING THUNDERSTORMS OVER THE REGION. FOR THIS REASON, AN  
INTERNAL HIGHER-END SLIGHT WAS ISSUED FOR THE SOUTHERN 2/3 OF THE  
STATE. THE SLIGHT INTO THE MID-APPALACHIANS WAS TRIMMED ON THE  
NORTHERN SIDE AROUND PITTSBURGH, PA DUE TO LESS MOISTURE MAKING IT  
THAT FAR NORTH AND EAST, AND WITH THE COLD FRONT OVER KENTUCKY  
CONCENTRATING THE STORMS FURTHER WEST, COVERAGE OF STORMS INTO WEST  
VIRGINIA ALSO APPEARS TO HAVE DIMINISHED IN THE GUIDANCE. THUS, THE  
SLIGHT WAS DROPPED TO A LOWER-END SLIGHT.  
 
AT THE WESTERN END OF THE FRONT INTO SOUTHEASTERN OKLAHOMA AND  
PARTS OF ARKANSAS, AN MCS MAY DEVELOP LATE THURSDAY NIGHT AS THE  
NOCTURNAL JET INTENSIFIES. A SLIGHT RISK WAS DRAWN IN FROM FAR  
NORTH TEXAS ALONG THE MO/AR BORDER TO THE MISSISSIPPI/OHIO RIVER  
CONFLUENCE FOR EXPECTED SLOW-MOVING AND TRAINING STORMS ALONG MUCH  
OF THE FRONT, THOUGH THE HIGHEST CONCENTRATION OF STORMS SHOULD BE  
INTO SOUTHEASTERN OKLAHOMA.  
 
WEGMAN  
 
 
DAY 4 AND DAY 5  
 
VALID 12Z FRI JUN 19 2026 - 12Z SUN JUN 21 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF  
THE SOUTHERN PLAINS, MID SOUTH, AND SOUTHERN APPALACHIANS ON DAY  
4...  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER THE PARTS OF  
THE MIDWEST ON DAY 5...  
 
DAY 4'S (FRIDAY) EXCESSIVE RAINFALL THREAT REMAINS FIXED ACROSS  
MUCH OF THE SOUTH. THE COMBINATION OF THE LINGERING DISTURBANCE,  
THAT MAY BECOME A MORE FORMIDABLE SURFACE CYCLONE, WILL RESIDE  
WITHIN AN ENVIRONMENT THAT CONTAINS >2.0" PWS OVER MUCH OF THE  
MID-SOUTH. SUFFICIENT INSTABILITY ALOFT WILL CONTINUE TO SUPPORT  
THUNDERSTORMS THAT CAN PRODUCE HIGHLY EFFICIENT RAINFALL RATES.  
MUCH OF THE REGION WILL ALSO HAVE RECEIVED A STEADY DOUSING OF  
HEAVY RAINFALL DURING THE WORK-WEEK AS WELL, PRIMING SOILS FOR MORE  
POTENTIAL FLASH FLOODING. FARTHER WEST, A SHORTWAVE TROUGH OVER TX  
AND THE RETURN OF LOW-LEVEL SERLY FLOW WILL INTRODUCE WILL  
REINTRODUCE MORE GULF MOISTURE OVER CENTRAL TX AND AS FAR WEST AS  
SOUTHWEST NM. THE TX HILL COUNTRY IS MOST PRONE TO FLASH FLOODING,  
ALTHOUGH SOME LOCALIZED FLASH FLOODING OVER THE GUADALUPE AND  
SACRAMENTO MOUNTAINS COULD ALSO TRANSPIRE.  
 
BY DAY 5 (SATURDAY), A POTENT 500MB SHORTWAVE TROUGH OVER THE GREAT  
BASIN WILL RACE EAST TOWARDS THE NORTHERN ROCKIES AROUND MIDDAY AND  
REACH THE NORTHERN HIGH PLAINS BY SATURDAY NIGHT. AS A COLD FRONT  
RACES SOUTH FROM CANADA, A WARM FRONT LIFTING NORTH THROUGH THE  
CENTRAL PLAINS WILL DELIVER A PLUME OF ANOMALOUS MOISTURE AND  
FOSTER AN INCREASINGLY UNSTABLE ENVIRONMENT OVER THE MIDWEST BY  
LATE SATURDAY. WHILE THE EXACT PLACEMENT OF THE DEVELOPING  
THUNDERSTORM ACTIVITY VARIES BY MODEL, THEY ALL SHOW A DEEPENING  
SURFACE LOW OVER THE CENTRAL PLAINS AND A STRENGTHENING LLJ THAT  
RESULTS IN A >500 KG/M/S IVT FIELD OVER THE MIDWEST. STORMS SHOULD  
BE ABLE TO PRODUCE EFFICIENT RAINFALL RATES THANKS TO A GROWING  
SHIELD OF >1.5" PWS OVER THE MO RIVER VALLEY, WHICH DOES SURPASS  
THE 90TH CLIMATOLOGICAL PERCENTILE. FOR THESE REASONS, A DAY 5  
SLIGHT RISK WAS INTRODUCED. FARTHER SOUTH, A WEAKENING FRONTAL  
BOUNDARY AND RESIDUAL ANOMALOUS MOISTURE ALOFT WILL HELP TRIGGER  
ADDITIONAL STORMS FROM SOUTH TX ON EAST ACROSS MANY OF THE GULF  
COAST STATES. GIVEN THE SOUTH'S INCREASINGLY SENSITIVE SOILS AND  
THE PRESENCE OF PWS HOVERING AROUND 2.0", THUNDERSTORMS COULD  
PRODUCE LOCALIZED FLASH FLOODING SATURDAY AFTERNOON AND EVENING.  
 
MULLINAX  
 
 
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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