032  
FOUS30 KWBC 111603  
QPFERD  
 
EXCESSIVE RAINFALL DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1203 PM EDT SAT JUL 11 2026  
 
DAY 1  
VALID 16Z SAT JUL 11 2026 - 12Z SUN JUL 12 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS  
ARIZONA AND THE SOUTHERN PLAINS TO THE CENTRAL APPALACHIANS...  
 
1600Z UPDATE -- MAIN CHANGE TO THE DAY 1 ERO WAS TO EXPAND THE  
MARGINAL RISK TO INCLUDE MUCH OF THE WESTERN AND CENTRAL GULF  
COAST. DEEP-LAYER BULK SHEAR VALUES DO REMAIN LOW (<20KTS), HOWEVER  
WEAK MID-LEVEL PERTURBATIONS (INCLUDING A H5 VORT ACROSS SOUTH TX)  
AND WEAK, BROAD CYCLONIC FLOW ALONG THE COAST WILL ALLOW FOR MORE  
ORGANIZED STORM CLUSTERS GIVEN MIXED LAYER CAPES BETWEEN 2000-3000  
J/KG AND PWS OF 2.0-2.3 INCHES.  
 
HURLEY  
 
PREVIOUS DISCUSSION...  
   
..OK INTO THE OH AND TN VALLEYS  
 
AN ACTIVE CONVECTIVE REGIME IS ANTICIPATED AHEAD OF A  
SOUTHEASTWARD MOVING SHORTWAVE TROUGH AXIS EXTENDING FROM MO TO OH.  
AT 12Z THIS MORNING, AN INITIAL ROUND OF CONVECTION WILL BE  
ONGOING FROM SOUTHERN IL INTO PORTIONS OF KY AND TN. MODEL GUIDANCE  
SUPPORTS A TRANSITION TOWARD A PRIMARILY FORWARD PROPAGATING  
CONVECTIVE MODE THIS MORNING, WHICH SHOULD PLACE THE OVERALL FLASH  
FLOOD RISK ON A DECLINING TREND, THOUGH LOCALIZED UPWIND  
PROPAGATION MAY KEEP AN ISOLATED THREAT GOING.  
 
BY THIS AFTERNOON, THE PRIMARY MCV/SHORTWAVE WILL SHIFT OVER IL  
AND IN, INTERACTING WITH A SOUTHWARD MOVING FRONTAL BOUNDARY TO  
TRIGGER SCATTERED REDEVELOPMENT ACROSS PORTIONS OF IL, IN AND WV.  
WITHIN THIS ZONE, PW VALUES NEAR OR JUST UNDER 2" WILL OVERLAP WITH  
CAPE OF 1000-2000 J/KG. WHILE WIDESPREAD CONVECTIVE ORGANIZATION  
IS NOT ANTICIPATED, SLOW CELL MOTIONS AND LOCALIZED MERGERS NEAR  
THE FRONTAL ZONE WILL SUPPORT HEAVY RAINFALL RATES CAPABLE OF  
PRODUCING LOCALIZED POCKETS OF 2-3" OF RAIN. THIS IS SUPPORTED BY  
THE 00Z HREF AND REFS, WHICH BOTH SHOW FFG EXCEEDANCE  
PROBABILITIES OF 15-40%.  
 
A MORE ORGANIZED, AND POTENTIALLY HIGHER END, FLASH FLOOD THREAT  
IS EXPECTED TO EVOLVE LATER THIS AFTERNOON INTO TONIGHT ACROSS  
PORTIONS OF KY AND TN. CONVECTION SHOULD DEVELOP TO THE SOUTH-  
SOUTHEAST OF THE MAIN SHORTWAVE/MCV, LIKELY FOCUSING ALONG REMNANT  
OUTFLOW BOUNDARIES AND INSTABILITY GRADIENTS LEFT BEHIND BY THE  
MORNING ACTIVITY. GLOBAL DETERMINISTIC AND AI MODELS FAVOR A HEAVY  
RAINFALL AXIS FOCUSED PRIMARILY FROM KY INTO NORTHEAST TN,  
WHEREAS HIGH RES MODELS (INCLUDING THE RRFS/REFS) SUGGEST THE CORE  
THREAT MAY TRACK FURTHER SOUTH INTO TN. GIVEN THE STRONG WESTERLY  
LOW LEVEL MOISTURE TRANSPORT SOUTH OF THE MCV, THE ENVIRONMENT  
WILL BE FAVORABLE FOR BACKBUILDING AND TRAINING CONVECTIVE CLUSTERS  
TONIGHT. THIS ENVIRONMENT, COMBINED WITH PWS HOVERING AROUND 2",  
SUGGESTS THAT MANY HREF MEMBERS MAY BE UNDERDOING THE  
AFTERNOON/NOCTURNAL THREAT. DO EXPECT TO SEE A SWATH OF HEAVY  
RAINFALL MATERIALIZE SOMEWHERE ACROSS THE KY/TN CORRIDOR, WHERE AN  
AXIS OF LOCALLY HIGHER END FLASH FLOOD IMPACTS IS POSSIBLE. A  
HIGHER END SLIGHT RISK IS MAINTAINED, WITH A MDT RISK UPGRADE NOT  
OUT OF THE QUESTION IF WE GAIN SPATIAL MODEL CONVERGENCE AND MORE  
CONFIDENCE ON EXACT CONVECTIVE MODE.  
 
FURTHER WEST, ISOLATED TO SCATTERED FLASH FLOODING IS ALSO EXPECTED  
ACROSS PORTIONS OF CENTRAL OK INTO AR. LOW LEVEL FLOW WILL BECOME  
CONVERGENT ON THE SOUTHWESTERN FLANK OF THE BROADER CONVECTIVE  
REGIME. SLOW CELL MOTIONS NEAR A BOUNDARY WILL POSE A THREAT OVER  
OK, WHILE ENHANCED NORTHERLY FLOW ON THE WESTERN PERIPHERY OF THE  
MCV/SHORTWAVE WILL CONVERGE WITH THE BROAD SOUTH-SOUTHWESTERLY  
INFLOW TO PROMOTE SOME BACKBUILDING/TRAINING THREAT OVER PARTS AR.  
   
..MID-ATLANTIC  
 
A LOCALIZED FLASH FLOOD THREAT IS FORECAST ACROSS PORTIONS OF THE  
MID-ATLANTIC. WHILE LOW LEVEL FLOW WILL BE NORTHERLY, ONE OR TWO  
LOW LEVEL CONVERGENCE AXES ARE PROJECTED TO SETUP ACROSS THE  
REGION, POTENTIALLY ACTING AS A FOCUS FOR CONVECTION. DESPITE THE  
NORTHERLY FLOW, AMPLE MOISTURE AND INSTABILITY WILL REMAIN IN  
PLACE. CONVECTIVE CELLS WILL GENERALLY TRACK FROM NORTH TO SOUTH,  
BUT LOCALIZED REPEATING CELLS WILL BE POSSIBLE ALONG THE TROUGH  
AXIS. THE STRONGEST SIGNAL FOR LOCALIZED 3" TOTALS WITH THE HREF  
RESIDES ALONG THE COASTAL PLAIN FROM NJ SOUTHWARD INTO SOUTHEAST  
VA WHERE CONVERGENCE IS ENHANCED. BECAUSE FFG VALUES ARE GENERALLY  
HIGHER HERE COMPARED TO INLAND LOCATIONS, THINK THE OVERALL FLASH  
FLOOD RISK SHOULD STAY ISOLATED, THOUGH LOCALIZED URBAN AND LOW  
LYING FLOOD IMPACTS ARE EXPECTED.  
   
..AZ AND NM  
 
THE PERSISTENT TERRAIN DRIVEN PATTERN CONTINUES ACROSS THE  
SOUTHWEST, WITH CONVECTION DEVELOPING OVER THE HIGHER ELEVATIONS  
BEFORE PROPAGATING SOUTHWESTWARD INTO A POOLING INSTABILITY AXIS  
OVER THE LOWER DESERTS OF SOUTHERN AZ. INSTABILITY AND MOISTURE  
PROFILES SHOULD BE A BIT HIGHER TODAY RELATIVE TO THE PAST FEW  
DAYS, LEADING TO A CORRESPONDING INCREASE IN THE OVERALL FLASH  
FLOOD RISK. BOTH THE 00Z HREF AND REFS DEPICT GREATER CONVECTIVE  
COVERAGE AND HIGHER LOCALIZED RAINFALL TOTALS. WHILE FAST  
SOUTHWESTWARD STORM PROPAGATION AND CELL SPEEDS MAY ACT AS A  
LIMITING FACTOR, THE MOISTURE/INSTABILITY FOOTPRINT SHOULD BE  
SUFFICIENT TO PROMOTE SOME CELL MERGERS AND LOCALIZED 1-2"/HR  
RAINFALL, JUSTIFYING THE MAINTENANCE OF THE SLIGHT RISK.  
 
A MARGINAL RISK HAS BEEN ADDED TO PORTIONS OF EASTERN NM. THIS AREA  
RECEIVED LOCALLY HEAVY RAIN YESTERDAY, AND THE MODEL QPF SIGNAL IS  
A BIT STRONGER TODAY WITHIN AN ENVIRONMENT CHARACTERIZED BY  
SLIGHTLY HIGHER MOISTURE AND INSTABILITY. CONVECTION SHOULD REMAIN  
ISOLATED TO SCATTERED, WITH THE PRIMARY FLASH FLOOD THREAT FOCUSED  
OVER RECENT BURN SCARS, PARTICULARLY ACROSS THE SACRAMENTO  
MOUNTAINS.  
   
..TX  
 
A MARGINAL RISK WAS ADDED TO PORTIONS OF THE TX HILL COUNTRY, WHERE  
PWS ARE FORECAST TO CLIMB ABOVE 2". ISOLATED TO SCATTERED  
CONVECTION IS EXPECTED WITHIN A BROAD SOUTHERLY LOW LEVEL FLOW  
REGIME. WHILE MOST CELLS WILL REMAIN TRANSIENT AND PRODUCE ONLY  
BRIEF DOWNPOURS, ANY CELLS THAT ESTABLISH MESOSCALE ORGANIZATION  
COULD BRIEFLY TRAIN OR BACKBUILD INTO THE LOW LEVEL INFLOW.  
GUIDANCE SUGGESTS A WEAK MCV CURRENTLY SOUTH OF THE RIO GRANDE  
THAT MAY TRACK NORTHWARD TOWARDS THE REGION LATER TODAY, WHICH  
COULD PROVIDE AN ADDITIONAL FOCUS FOR ASCENT. THE RISK AREA ALIGNS  
CLOSELY WITH THE HREF AND REFS 1" EAS PROBABILITIES OF 10-20%  
(SIGNALING ORGANIZATION POTENTIAL), AND 3" NEIGHBORHOOD  
PROBABILITIES EXCEEDING 40%. GLOBAL DETERMINISTIC AND AI SUITES  
ALSO SHOW A DISTINCT CONVECTIVE FOCUS OVER THIS CORRIDOR.  
 
CHENARD  
 
 
DAY 2  
VALID 12Z SUN JUL 12 2026 - 12Z MON JUL 13 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF  
EASTERN KENTUCKY AND TENNESSEE INTO THE CAROLINAS..  
   
..SOUTHEAST QUARTER OF THE COUNTRY  
 
A SLIGHT RISK HAS BEEN INTRODUCED STRETCHING FROM KY AND TN  
EASTWARD INTO SOUTHERN VA AND THE CAROLINAS. A WELL DEFINED  
SHORTWAVE/LOW OVER THE KY/TN VICINITY WILL INTERACT WITH A SLOW  
MOVING BACKDOOR FRONT TO FOCUS ORGANIZED CONVECTION. HIGH RES  
GUIDANCE, INCLUDING THE RRFS, FV3 AND 3KM NAM, INDICATES A  
CONCENTRATED AXIS OF CONVECTION CAPABLE OF PRODUCING LOCALIZED  
TOTALS EXCEEDING 3". WHILE THE GLOBAL GFS AND ECMWF ARE LESS  
PRONOUNCED WITH THEIR QPF SWATHS THE GEM REGIONAL AND UKMET ARE  
MORE IN LINE WITH THE HIGH RES GUIDANCE. THE AIFS AND AIGFS ALSO  
DEPICT A CORRIDOR OF ENHANCED QPF THAT GENERALLY MATCHES THE SLIGHT  
RISK PLACEMENT. BENEATH THE CLOSED LOW OVER KY AND TN, CONVECTION  
MAY BE LESS ORGANIZED, BUT SLOW MOVING. GIVEN PWS NEAR 2" AND THE  
POSSIBILITY OF SATURATED SOILS FROM DAY 1 RAINFALL, A FLASH FLOOD  
RISK SHOULD CONTINUE. ACROSS THE CENTRAL AND EASTERN CAROLINAS PWS  
OVER 2" COMBINED WITH LOW LEVEL SOUTHERLY MOISTURE TRANSPORT AND  
BACKDOOR FRONTAL CONVERGENCE SHOULD CREATE AN ENVIRONMENT FOR HIGH  
RAINFALL RATE DRIVEN FLASH FLOOD POTENTIAL.  
 
SURROUNDING THE SLIGHT RISK, A BROAD MARGINAL ENCOMPASSES EASTERN  
NM, TX AND MUCH OF THE SOUTHEAST. A SOUTHWARD ADVANCING COLD FRONT,  
THE AFOREMENTIONED MID LEVEL SHORTWAVE/LOW, AND UPPER JET SUPPORT  
WILL PROVIDE THE NECESSARY SYNOPTIC FORCING FOR SCATTERED  
CONVECTION. PWS OVER 2" AND CAPE OF 2000-3000 J/KG WHERE DAYTIME  
HEATING IS MAXIMIZED, WILL SUPPORT HEAVY RAINFALL RATES. SOME  
MESOSCALE UNCERTAINTY EXISTS WITH THE TRACK AND STRENGTH OF THE  
SHORTWAVE AND FRONTAL POSITIONS. AN EMBEDDED SLIGHT RISK OR TWO  
MAY BE NEEDED ON FUTURE UPDATES AS CONFIDENCE INCREASES. INCREASING  
LOW LEVEL WESTERLY FLOW ALONG THE CENTRAL GULF COAST PROVIDES A  
SIGNATURE FOR BACKBUILDING AND TRAINING, BUT MODEL DIVERGENCE ON  
THE EXACT AXIS REMAINS. GIVEN THE HIGHER REGIONAL FFG, DID NOT  
WANT TO GO WITH AN OVERLY LARGE SLIGHT RISK AT THIS TIME.  
   
..SOUTHWEST  
 
MONSOONAL MOISTURE AND INSTABILITY WILL EXPAND NORTHWESTWARD ON  
SUNDAY, NECESSITATING A BROADER MARGINAL RISK ACROSS AZ. WHILE AN  
EMBEDDED SLIGHT RISK MAY EVENTUALLY BE NEEDED, LINGERING QUESTIONS  
REGARDING STORM COVERAGE AND ORGANIZATION KEEP THE RISK AT  
MARGINAL FOR NOW. CURRENT INDICATIONS SUGGEST THAT WHILE ROBUST  
CONVECTION WILL INITIATE OVER THE TERRAIN, IT WILL PROPAGATE  
WESTWARD QUICKLY, POTENTIALLY LIMITING THE THREAT TO ISOLATE  
INSTANCES OF FLASH FLOODING.  
 
CHENARD  
 
 
DAY 3  
VALID 12Z MON JUL 13 2026 - 12Z TUE JUL 14 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF  
THE CENTRAL GULF COAST...  
   
..CENTRAL GULF COAST TO THE SOUTHEAST  
 
THE INHERITED SLIGHT RISK ACROSS PORTIONS OF THE CENTRAL GULF COAST  
HAS BEEN MAINTAINED AND EXPANDED BOTH WESTWARD INTO SOUTHEAST TX  
AND EASTWARD INTO THE FL PANHANDLE. A FAVORABLE SYNOPTIC AND  
MESOSCALE SETUP FOR TRAINING AND BACKBUILDING IS FORECAST TO ALIGN  
WITH COASTAL AREAS. ENHANCED WEST TO NORTHWESTERLY LOW LEVEL FLOW  
SOUTH OF THE PERSISTENT SHORTWAVE/LOW OVER THE TN/GA VICINITY WILL  
CONVERGE WITH SOUTHWESTERLY INFLOW OFF THE GULF. THIS CONFIGURATION  
IS CONDUCIVE FOR UPWIND PROPAGATION AND SOME TRAINING CONVECTION.  
WHILE SOME UNCERTAINTY REMAINS REGARDING HOW FAR INLAND THE HEAVIER  
TOTALS WILL REACH, THE MOIST AIRMASS CHARACTERIZED BY PWS AROUND  
2.25" WILL SUPPORT HEAVY RAINFALL RATES.  
 
FURTHER WEST, INCREASING LOW LEVEL SOUTHERLY MOISTURE TRANSPORT  
OUT OF THE WESTERN GULF WILL PUSH UP THE RIO GRANDE VALLEY AND INTO  
CENTRAL TX, POTENTIALLY RESULTING IN CONVECTIVE CLUSTERS MONDAY  
NIGHT. FUTURE SHIFTS MAY NEED TO EXPAND THE SLIGHT RISK EVEN  
FURTHER INTO TX DEPENDING ON HOW THIS THREAT EVOLVES.  
 
A BROAD MARGINAL RISK REMAINS IN PLACE FROM TN INTO THE SOUTHEAST  
AND SOUTHERN MID-ATLANTIC, SIMILAR TO DAY 2, A LINGERING  
SHORTWAVE/LOW WILL CONTINUE TO INTERACT WITH A BACKDOOR FRONTAL  
ZONE. MODEL DIVERGENCE EXISTS REGARDING THE EXACT POSITIONING OF  
THESE FEATURES AND THE AVAILABLE INSTABILITY FOOTPRINT BY THIS  
TIME. GIVEN THIS, AND THE FACT THAT MODEL QPF SIGNALS ARE A BIT  
MORE MUTED COMPARED TO SUNDAY, WE WILL MAINTAIN THE MARGINAL  
RISK...ALTHOUGH AN EMBEDDED SLIGHT RISK UPGRADE MAY STILL  
EVENTUALLY BE NEEDED AS THE MESOSCALE DETAILS CLARIFY.  
   
..SOUTHWEST  
 
A MARGINAL RISK IS MAINTAINED FROM SOUTHERN NM INTO AZ, SOUTHEAST  
CA AND SOUTHERN NV. DEEP MONSOONAL MOISTURE WILL CONTINUE TO PUSH  
NORTHWESTWARD WITH ISOLATED TO SCATTERED CONVECTION EXPECTED TO  
RESULT IN AT LEAST A LOCALIZED FLASH FOOD THREAT.  
 
CHENARD  
 
 
DAY 4 AND DAY 5  
 
VALID 12Z TUE JUL 14 2026 - 12Z THU JUL 16 2026  
 
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ALONG PARTS OF THE  
CENTRAL GULF COAST ON MONDAY...  
   
..SOUTHEAST U.S. INTO TEXAS  
 
LINGERING EFFECTS FROM ELEVATED MOISTURE AND SLOWLY DECAYING  
QUASI-STATIONARY FRONT ACROSS THE SOUTHEAST U.S. WILL LEAD TO ONE  
LAST PERIOD OF ELEVATED CONVECTIVE ENHANCEMENTS FROM EAST TX  
THROUGH THE SOUTHERN HALF OF THE SOUTHEASTERN CONUS. PWAT ANOMALIES  
WILL REMAIN GENERALLY SEASONAL TO PERHAPS UPWARDS OF +1 STANDARD  
DEVIATIONS OVER THE REGION, ENOUGH OF A THREAT FOR HEAVY RAIN  
PROSPECTS IN A ENVIRONMENT THAT FAVORS RELATIVELY SLOWER CELL  
MOTIONS. CONSIDERING THE FACT SOME OF THE SOUTHEAST WILL HAVE  
RECEIVED A FORMIDABLE AMOUNT OF RAINFALL LEADING INTO THE D4, SOME  
LOCALIZED FLASH FLOOD CONCERNS WILL LINGER FOR AT LEAST ONE MORE  
DAY BEFORE FINALLY WANING INTO THE D5 WHERE THE RISK OVER THE  
SOUTHEAST IS VOID AND WE SETTLE INTO A MORE BENIGN PATTERN OVERALL.  
 
FURTHER WEST INTO THE WESTERN HALF OF TX, THE SAME STORY CANNOT BE  
SAID AS THE PATTERN WILL BEGIN SHAPING UP INTO A MUCH MORE  
FAVORABLE FLASH FLOOD ENVIRONMENT THANKS TO A SHIFT IN THE MID AND  
UPPER LEVEL PATTERN WEST OF THE MISSISSIPPI. DOMINANT RIDGING OVER  
THE TOP INTO THE NORTHERN TIER OF THE CONUS WILL GIVE WAY TO  
A BROAD INVERTED TROUGH AXIS MIGRATING WESTWARD INTO THE SOUTHERN  
PLAINS AS WE MOVE INTO THE MIDDLE OF NEXT WEEK LEADING TO WEAKENING  
FLOW ALOFT AND A MYRIAD OF SMALLER MID-LEVEL PERTURBATIONS ROTATING  
UNDER THE DOMINANT CYCLONIC FLOW. LOWERING HEIGHTS AND REGIONAL  
FORCING ALIGN TO FOSTER A MORE SUITABLE CONVECTIVE ENVIRONMENT  
ACROSS THE WESTERN HALF OF TX WITH AN EMPHASIS CURRENTLY ON  
WEST AND SOUTHWEST TX AS NOTED VIA THE MULTI-MODEL CONSENSUS IN  
BOTH THE DETERMINISTIC AND ENSEMBLE OUTPUTS. SOME OF THE GUIDANCE  
IS INCREDIBLY AGGRESSIVE IN THEIR PRESENTATIONS WITH SEVERAL INCHES  
OF RAIN IN BOTH THE D4 AND D5 TIME FRAMES WITH A GENERAL MAXIMA  
LOCATED OVER THE LOWER TRANS PECOS OVER INTO THE NEIGHBORING  
EDWARDS PLATEAU WHERE THE PATTERN WOULD ALLOW FOR GREATER LOW-LEVEL  
CONVERGENCE AND PROSPECTS FOR ORGANIZED CONVECTIVE CLUSTERS TO  
SNEAK OUT OF MEXICO (MEXICAN STATE OF COAHUILA). CONSIDERING A  
SOLID AGREEMENT WITHIN THE MODEL SUITE THIS EVENING, FELT CONFIDENT  
ENOUGH TO INTRODUCE A SLGT RISK ACROSS SOUTHWEST TX OVER INTO THE  
EDWARDS PLATEAU AND PORTIONS OF THE CENTRAL RGV. THIS IS CERTAINLY  
AN AREA TO MONITOR CLOSELY AS SIGNIFICANT RAINFALL POTENTIAL IS  
PLAUSIBLE IN THE CURRENT SYNOPTIC EVOLUTION BEING DEPICTED.  
   
..SOUTHWEST U.S  
 
THE SOUTHWESTERN U.S. WILL LIE WITHIN THE WESTERN FLANK OF THE  
BROAD RIDGE PATTERN OVER THE CENTRAL AND EASTERN U.S WHICH WILL  
PROVIDE A DOMINANT SOUTHERLY FLOW OVER THE REGION ALLOWING FOR  
CONTINUED MOISTURE ADVECTION AND ENHANCED SURFACE TROUGHING OVER AZ  
UP THROUGH THE GREAT BASIN. THIS PATTERN IS A CONTINUATION OF THE  
MONSOONAL PRESENCE OUT WEST WITH A POTENTIAL FOR INCREASING FLASH  
FLOOD PROSPECTS AS MULTI-DAY IMPACTS COULD SPUR TARGETED  
OPPORTUNITIES FOR REPETITION OF AREAS GETTING HIT BY CONVECTION IN  
CONSECUTIVE PERIODS. THIS SETUP REMAINS VERY STABLE IN TERMS OF THE  
BROAD SYNOPTIC PATTERN IN PLACE OVER THE WESTERN CONUS, HOWEVER WE  
WILL SEE A PERSISTENT MOISTURE PLUME ADVECT MORE FORMIDABLE DEEP  
LAYER MOISTURE POLEWARD AS WE MOVE INTO EARLY-MID NEXT WEEK LEADING  
TO PWAT ANOMALIES PUSHING THE 90-99TH PERCENTILE ACCORDING TO THE  
NAEFS AND 00Z ECENS OUTPUTS. THE STRONGEST ANOMALIES WILL LIE  
WITHIN THE GREAT BASIN UP INTO THE NORTHERN ROCKIES ON D4 WITH SOME  
MODIFICATION BY D5, BUT STILL VERY MUCH ENTRENCHED WITHIN THE UPPER  
BOUNDS OF THE ANOMALIES, ESPECIALLY OVER THE NORTHERN ROCKIES AND  
INTERIOR NORTHWEST. INCREASED UPPER TROUGHING MIGRATING FROM THE  
WEST WILL SLIDE UNDER THE RIDGE ACROSS THE NORTHERN CONUS LEADING  
TO AN ENHANCEMENT FOR CONVECTIVE POTENTIAL OVER A BROADER SCOPE BY  
D5 WITH WIDESPREAD THUNDERSTORM PROSPECTS ALIGNED FROM THE CANADIAN  
BORDER IN MT DOWN THROUGH THE INTER-MOUNTAIN WEST INTO THE  
SOUTHWESTERN DESERTS. THIS SETUP CAN LEAD TO SNEAKY SIGNIFICANT  
RAINFALL PROSPECTS FOR THOSE IN THE INTERIOR WITH A MORE TYPICAL  
MONSOONAL PRESENTATION IN THE CONVECTIVE COVERAGE.  
 
GIVEN THE ABOVE VARIABLES, THE MRGL WAS EXPANDED NORTH AND  
NORTHWEST FOR D4 INTO THE GREAT BASIN WITH ANOTHER MRGL RISK ADDED  
ACROSS THE NORTHERN ROCKIES IN THE WESTERN HALF OF MT AND NORTHERN  
ID. D5 IS A BROAD MRGL RISK FOR MUCH OF THE SOUTHWEST AND INTERIOR  
WEST, INCLUDING AREAS THAT WERE OMITTED FROM THE PREVIOUS PERIOD(S)  
MRGL RISKS. THERE IS POTENTIAL FOR TARGETED SLGT RISKS TO BE ISSUED  
IN FUTURE UPDATES AS WE MOVE CLOSER TO THE EVENT, SO PLEASE CHECK  
BACK OVER THE NEXT SEVERAL DAYS AS THE PATTERN BECOMES MUCH MORE  
ACTIVE AND FAVORABLE FOR FLASH FLOOD PROSPECTS.  
 
KLEEBAUER  
 
 
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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