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FOUS30 KWBC 102234
QPFERD
EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
634 PM EDT FRI APR 10 2026
DAY 1
VALID 2200Z SAT APR 11 2026 - 12Z SAT APR 11 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE CENTRAL-SOUTHERN PLAINS AND PARTS OF SOUTHEAST TEXAS...
2200Z UPDATE:
HAVE HOISTED A MARGINAL RISK AREA ACROSS PARTS OF SE TX, TO INCLUDE
PORTIONS OF THE MID-UPPER TX COAST, ENCOMPASSING THE HOUSTON-
GALVESTON METROS. DEEP-LAYER CAPES OF 1500-2000 J/KG ALONG WITH
PWAT VALUES ~1.75" IS PROVIDING A FAVORABLE THERMODYNAMIC
ENVIRONMENT IN THE VICINITY OF A WEAK/UNORGANIZED MID-LEVEL VORT
LOBE. MEANWHILE, SOUTHEASTERLY LOW-LEVEL INFLOW (~15KTS) IS DOUBLE
THE MAGNITUDE OF THE MEAN DEEP-LAYER WEST-SOUTHWESTERLY FLOW,
WHICH WILL ALLOW FOR SOME TRAINING OF CONVECTION. LOCALIZED
RAINFALL RATES OF 2+ IN/HR WILL BE POSSIBLE WITHIN THE STRONGEST
CONVECTIVE CLUSTERS, WHICH COULD PRODUCE ISOLATED URBAN FLASH
FLOODING. FOR FURTHER DETAILS, PLEASE REFER TO THE THE MESOSCALE
PRECIPITATION DISCUSSION OR MPD #88.
ELSEWHERE, WE HAVE ALSO EXPANDED THE PLAINS MARGINAL RISK AREA A
BIT FARTHER WEST AND SOUTH TO INCLUDE MORE OF CENTRAL OK, THE OK-TX
PANHANDLES, AND A PORTION OF NORTHEAST NM. THIS WAS BASED PARTIALLY
ON CURRENT OBSERVATIONAL AND MESOANALYSIS TRENDS, WITH DEEP-LAYER
CAPES LATE THIS AFTERNOON NOW 2000-2500 J/KG ACROSS MUCH OF THIS
AREA, INCLUDING ~2,000 J/KG ACROSS PARTS OF THE TX PANHANDLE INTO
NORTHEAST NM. MEANWHILE, THE 18Z HREF QPF EXCEEDANCE PROBABILITIES
(PROBABILITIES OF 1-2 IN/HR RATES AND AT LEAST 3"/3HR) ALSO
SOMEWHAT DICTATED THE AREAL-EXTENT OF THE MARGINAL RISK AREA, ALONG
WITH THE LATEST CSU ERO UFVS-VERIFIED FIRST GUESS FIELD.
HURLEY
PREVIOUS DISCUSSION:
A WEST-EAST ORIENTATED FRONTAL BOUNDARY WILL BE DROPPING SOUTHWARD
THROUGH THE PERIOD WHILE PW VALUES OF +2-2.5 STANDARD DEVIATIONS
ADVECT NORTHWARD ACROSS THE REGION AS THE LOW LEVEL FLOW
STRENGTHENS. MEANWHILE, SHORTWAVE ENERGY PUSHING NORTHEASTWARD INTO
THIS HIGH PW AXIS IN THE VICINITY OF THIS FRONT WILL SUPPORT AREAS
OF SLOW MOVING CONVECTION ALONG THIS FRONT, LOCALLY HEAVY RAINS
AND ISOLATED RUNOFF ISSUES. HREF NEIGHBORHOOD PROBABILITIES SHOW
40-70% FOR 2 INCHES AND 20-40 % FOR 3 INCHES OF RAINFALL ACROSS
THESE AREAS. WHILE AREAL AVERAGES ARE GENERALLY EXPECTED TO BE LESS
THAN 1.5 INCHES, THERE ARE SIGNALS FOR ISOLATED MAXIMUMS OF 3-4+
INCHES PER THE LATEST CAM GUIDANCE. THE MARGINAL RISK AREA FOR
EXCESSIVE RAINFALL WAS MAINTAINED FROM THE OKLAHOMA/TEXAS
PANHANDLES TO SOUTHWEST MISSOURI.
WILDER/CAMPBELL
DAY 2
VALID 12Z SAT APR 11 2026 - 12Z SUN APR 12 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHERN PLAINS...
..SOUTHERN PLAINS
GULF MOISTURE WILL CONTINUE TO ADVECT NORTHWARD WITH PW ANOMALIES
ABOVE SEASONAL NORMALS ACROSS THE SOUTHERN PLAINS. UPPER DYNAMICS
WILL SUPPORT ASCENT AHEAD OF A LONGWAVE TROUGH ENTERING THE WEST
COAST, AS WELL AS EMBEDDED SHORT WAVES. AS RIDGING BUILDS IN
ACROSS THE EAST, THIS WILL ALSO PROMOTE STRONG SOUTHERLY FLOW AND A
LOW LEVEL JET OVER THE SOUTHERN PLAINS TO CONTINUE TO ADVECT
MOISTURE AND INSTABILITY INTO THE AREA. AT THE SURFACE, A DRY LINE
ACROSS WEST TEXAS WILL HELP SERVE AS AN INITIATING MECHANISM FOR
CONVECTION IN THE AFTERNOON. THUNDERSTORM ACTIVITY WILL MIGRATE
EASTWARD THROUGH THE PERMIAN BASIN AND WESTERN ROLLING PLAINS,
EVENTUALLY MAKING HEADWAY INTO THE ADJACENT CONCHO VALLEY AND LOWER
TRANS PECOS. AS CELLS MERGE DUE TO COLD POOL MERGERS AND LOW-LEVEL
JET INITIATION, A LARGE CLUSTER OF HEAVY RAINFALL WILL ENSUE
THROUGH THE REST OF SATURDAY NIGHT INTO SUNDAY MORNING.
THE LATEST MODEL GUIDANCE REMAINS UNCHANGED IN DEPICTING A SIGNAL
FOR 2-4 INCHES POSSIBLE FROM THE CONCHO VALLEY IN WEST TEXAS TO THE
RED RIVER VALLEY IN SOUTHERN OKLAHOMA. NEIGHBORHOOD 24 HR QPF HREF
PROBABILITIES SHOW A STRONG SIGNAL FOR 50-80% FOR 2 INCHES FOR
THIS REGION AND 40-70% FOR 3 INCHES. A SLIGHT RISK FOR EXCESSIVE
RAINFALL REMAINS IN EFFECT ACROSS PORTIONS OF THE SOUTHERN PLAINS,
ESPECIALLY THE AREAS REFERENCED ABOVE.
..UPPER MIDWEST AND GREAT LAKES
A MARGINAL RISK FOR EXCESSIVE RAINFALL WAS INTRODUCED ACROSS
WISCONSIN AND NORTHERN MICHIGAN. MOISTURE WILL INCREASE ALONG A
WARM FRONT LIFTING NORTHWARD THROUGH THE REGION AND WILL LIKELY
SEE STORMS FIRE ALONG THE BOUNDARY DURING THE AFTERNOON. THE
OVERALL QPF FOOTPRINT LOOKS FAIRLY MODEST IN THE 1" RANGE, BUT
HYDROLOGICAL CONCERNS FROM MELTING SNOW AND HIGH RIVER LEVELS MAY
ALLOW FOR RUNOFF CONCERNS. FLASH FLOODING PROSPECTS WILL BE MORE
ISOLATED IN GENERAL, HOWEVER, WE WILL BE MONITORING THE COMBINATION
OF SNOW MELT AND HEAVY RAINFALL VERY CAREFULLY AS HIGH SWE LEVELS
OVER THE NORTHERN GREAT LAKES ARE LIKELY TO POSE PROBLEMS IN THE
NEXT SEVERAL DAYS. A FLOOD WATCH IS ALREADY IN EFFECT ACROSS THE
MICHIGAN U.P. AS A RESULT OF THE IMPENDING PATTERN.
WILDER/CAMPBELL
DAY 3
VALID 12Z SUN APR 12 2026 - 12Z MON APR 13 2026
..THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL FOR CENTRAL TEXAS
..CENTRAL TEXAS
MULTIPLE ROUNDS OF STRONG TO SEVERE STORMS WILL PERSIST ACROSS THE
SOUTHERN/CENTRAL PLAINS AND LOWER MISSISSIPPI VALLEY GIVEN HIGH
MOISTURE PRESENCE, FAVORABLE WIND SHEAR AND INSTABILITY IN PLACE.
A MEANDERING DRY LINE ACROSS THE REGION WILL PROVIDE A FOCUS FOR
BACKBUILDING CELLS. WITH LIMITED EASTWARD PROGRESSION OF THE QPF
FOOTPRINT EXPECTED DURING THIS PERIOD, THERE IS A GROWING THREAT
FOR FLASH FLOOD CONCERNS ACROSS PORTIONS OF HILL COUNTRY TO THE I-35
CORRIDOR SOUTH OF DALLAS. A SLIGHT RISK FOR EXCESSIVE RAINFALL IS
NOW IN EFFECT FOR CENTRAL TEXAS FOR THE THREAT WITH A MARGINAL RISK
EXTENDING NORTHEASTWARD THROUGH OKLAHOMA AND ADJACENT AREAS OF
KANSAS/MISSOURI/ARKANSAS.
..NORTHERN MICHIGAN
A MARGINAL RISK FOR EXCESSIVE RAINFALL REMAINS ACROSS NORTHERN
MICHIGAN ON SUNDAY AS MOISTURE TRANSPORT FROM THE SOUTH WILL
INTERACT WITH A FRONTAL BOUNDARY ACROSS NORTHERN MICHIGAN. THIS WILL
PROVIDE A LIFTING MECHANISM FOR ADDITIONAL SHOWERS AND
THUNDERSTORMS. MODEL GUIDANCE AVERAGED AROUND 1-2 INCHES OF RAIN IN
THE 24 HOUR PERIOD. SNOW MELT CONCERNS AND HIGH RIVER LEVELS WILL
INCREASE THE POSSIBILITY FOR RUN-OFF, SIMILARLY TO SATURDAY. THE
AREA OF INTEREST WILL SHIFT A BIT EAST TO ENCOMPASS MORE OF THE
EASTERN MICHIGAN U.P., AS WELL AS THE NORTHERN PORTION OF THE MITT
IN MICHIGAN.
WILDER/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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