509  
FXUS02 KWBC 012000  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
300 PM EST SUN MAR 1 2026  
 
VALID 12Z WED MAR 04 2026 - 12Z SUN MAR 08 2026  
   
..EMERGING EAST-CENTRAL U.S. HEAVY RAINFALL PATTERN THIS WEEK  
 
   
..GUIDANCE/PREDICTABILITY ASSESSMENT  
 
GUIDANCE UNCERTAINTY IN THE UPCOMING MEDIUM-RANGE PERIOD BEGINS  
PRIMARILY FOCUSED ACROSS THE PLAINS AND VICINITY MID-LATER WEEK.  
RECENT GFS/GEFS CONTINUES TO ADVERTISE A FRONTAL WAVE TO TRACK  
NORTHEASTWARD ACROSS THE MIDWEST. THIS SOLUTION REMAINS MORE  
AMPLIFIED THAN THE REST OF THE DYNAMICAL SOLUTIONS THAT DIG ENERGY  
MORE SHARPLY THROUGH THE WEST. THE AI MODELS FAVOR A DELAYED  
AMPLIFICATION RELATIVE TO THE GFS/GEFS BUT THEY HAVE COME INTO  
BETTER AGREEMENT TODAY. THE ECMWF REMAINS THE LEAST AMPLIFIED  
GUIDANCE REGARDING THIS WAVE. THEREAFTER, ANOTHER UPPER-LEVEL  
TROUGH/WAVE IS NOW MORE UNIFORMLY FORECAST IN GUIDANCE TO DIG MORE  
THROUGH THE WEST TO THE SOUTHWEST/BAJA NEXT WEEKEND, BUT ALSO  
ALLOW FOR RENEWED GULF RETURN FLOW DOWNSTREAM IN CHANNELED FLOW ON  
THE WESTERN TO NORTHERN PERIPHERY OF A BUILDING/WARMING SOUTHWEST  
U.S./ATLANTIC UPPER TROUGH. THIS WILL SET ANOTHER STAGE FOR THE  
NEXT BOUT OF HIGH QPF INTO NEXT WEEKEND FROM THE SOUTH-CENTRAL  
PLAINS TO THE MIDWEST IN A REGION HAVING JUST EXPERIENCED  
WIDESPREAD RAINFALL/CONVECTION.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS  
 
A PRONOUNCED SPLIT UPPER FLOW PATTERN WILL DOMINATE THE NATION THIS  
WEEK. A LEADING SOUTHERN STREAM UPPER TROUGH AND SURFACE SYSTEM  
WILL EJECT FROM THE SOUTH-CENTRAL U.S. THROUGH THE MIDWEST THEN  
NORTHEAST MID-LATE WEEK AND RETURN INFLOW WILL FUEL AN EMERGING  
AREA OF MODERATE TO HEAVY RAINS/CONVECTION UNDER A FAVORABLE UPPER  
JET. THE DAY 4 & 5 (WEDNESDAY/THURSDAY) WPC EXCESSIVE RAINFALL  
MARGINAL THREAT AREAS WERE REDUCED GIVEN THE FOCUS OF HIGHEST QPFS  
IS NOW ACROSS THE SOUTHERN PLAINS TO THE MID-MISSISSIPPI VALLEY  
BASED ON THE LATEST FROM GUIDANCE. OVERRUNNING MOISTURE INTO COLD  
CANADIAN HIGH PRESSURE SLIDING INTO THE U.S. NORTHERN TIER AS  
DRIVEN BY MORE PROGRESSIVE NORTHERN STREAM ENERGIES SHOULD ALSO  
SUPPORT A SWATH OF SNOW FROM NORTHERN PORTIONS OF THE UPPER  
MIDWEST/GREAT LAKES TO THE INTERIOR NORTHEAST WHERE CONDITIONS MAY  
ALSO SUPPORT AN ICY TRANSITION ZONE TO MONITOR.  
 
MEANWHILE UPSTREAM, AN AMPLIFIED UPPER TROUGH WILL DIG SHARPLY  
SOUTHEASTWARD INTO THE WEST FROM THE PACIFIC NORTHWEST TO THE  
SOUTHWEST/ROCKIES WEDNESDAY-FRIDAY AND BRING UNSETTLED AND COOLING  
FLOW ALONG WITH A WIDESPREAD MODERATE PRECIPITATION FOCUS FROM THE  
PACIFIC NORTHWEST THROUGH THE NORTH-CENTRAL INTERMOUNTAIN/ROCKIES  
TO INCLUDE TERRAIN ENHANCED SNOWS. WHILE RECENT GUIDANCE TRENDS DIG  
AN INCREASING SOUTHERN STREAM DETACHED UPPER LOW/TROUGH THROUGH  
THE SOUTHWEST INTO BAJA NEXT WEEKEND, DOWNSTREAM ENERGY TRANSLATION  
SHOULD ALSO ACT TO RENEW THE WET/CONVECTIVE FLOW PATTERN NEXT  
WEEKEND AGAIN OVER THE SOUTH-CENTRAL U.S. TO MIDWEST TO MONITOR FOR  
RUNOFF ISSUES GIVEN AMPLE EARLIER RAINFALL TO MOISTEN SOILS.  
ADDITIONAL FLOW FROM THE NORTHEAST PACIFIC MAY ALSO WORK BACK INTO  
THE NORTHWEST TO RENEW MODERATE PRECIPITATION NEXT WEEKEND AND  
CONTINUED NORTHERN STREAM ENERGY TRANSLATION INTO CYCLONIC UPPER  
FLOW DOWNSTREAM INTO THE NORTHERN TIER COULD ALSO ALLOW FOR SOME  
COOLER AIRMASS INTRUSIONS TO INTERACT WITH THE NORTHERN FRINGE OF  
THE AFOREMENTIONED EXPANDING SOUTHERN STREAM PRECIPITATION AREA.  
 
IN THIS PATTERN, AMPLIFIED SOUTHEAST/ATLANTIC UPPER RIDGING AND  
SIGNIFICANT SPRINGTIME WARMING WILL BUILD AND LINGER UP THE EAST  
COAST THROUGH LATER NEXT WEEK/WEEKEND AS LEAD COLD DAMNED HIGH  
PRESSURE MODERATES AND LOSES SOUTHWARD INFLUENCE.  
 
KONG/SCHICHTEL  
 
ADDITIONAL 3-7 DAY HAZARD INFORMATION CAN BE FOUND ON THE WPC  
MEDIUM RANGE HAZARDS OUTLOOK CHART AT:  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP  
 
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,  
QUANTITATIVE PRECIPITATION FORECAST (QPF), EXCESSIVE RAINFALL  
OUTLOOK (ERO), WINTER WEATHER OUTLOOK (WWO) PROBABILITIES, HEAT  
INDICES, AND KEY MESSAGES CAN BE ACCESSED FROM:  
 
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST500_WBG.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST_WBG_CONUS.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/5KM_GRIDS/5KM_GRIDSBODY.HTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/DAY4-7.SHTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=ERO  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=OVW  
 
 
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