629  
FXUS02 KWBC 251901  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
300 PM EDT FRI MAR 25 2022  
 
VALID 12Z MON MAR 28 2022 - 12Z FRI APR 01 2022  
 
...WET WEATHER MOVING THROUGH SOUTHERN CALIFORNIA EARLY NEXT WEEK  
WILL BE FOLLOWED BY LOW PRESSURE SYSTEM INTENSIFYING OVER THE  
PLAINS MID-LATE WEEK TO BRING HEAVY RAIN/SEVERE WEATHER ACROSS THE  
SOUTH AND INCREASING POTENTIAL OF HEAVY SNOW/ICE ACROSS THE UPPER  
GREAT LAKES TO UPPER MIDWEST...  
   
..OVERVIEW
 
 
AN AMPLIFIED UPPER TROUGH AND LINGERING WINTRY WEATHER WILL EXIT  
THE NORTHEASTERN U.S. BY EARLY NEXT WEEK, FOLLOWED BY A GRADUAL  
MODERATION OF A POLAR AIRMASS ACROSS THE NORTH-CENTRAL THROUGH  
EASTERN STATES. THE MAIN WEATHER FOCUS ACROSS THE NATION WILL  
THEN SHIFT TO THE WEST AS A STRONG UPPER TROUGH AND EMBEDDED  
CLOSED LOW PROGRESS INTO AND THROUGH THE SOUTHWESTERN STATES EARLY  
NEXT WEEK. AS THE SYSTEM LIFTS ACROSS THE SOUTH-CENTRAL  
ROCKIES/PLAINS MIDWEEK, MODEL GUIDANCE CONTINUES TO TREND TOWARD  
SUPPORTING ADDITIONAL PHASING WITH NORTHERN STREAM TROUGH ENERGIES  
DIGGING INTO THE NORTHERN PLAINS MID TO LATE WEEK THAT WOULD  
PROMOTE MORE SOLID INTENSIFICATION OF A SURFACE LOW AND ASSOCIATED  
FRONTAL SYSTEMS. OVERALL, THIS WILL FAVOR RATHER UNSETTLED AND  
WET PATTERN FROM CA AND THE SOUTHWEST TO THE SOUTH-CENTRAL ROCKIES  
EARLY NEXT WEEK (INCLUDING MOUNTAIN SNOWS) THAT WILL EMERGE/  
EXPAND IN MAGNITUDE AND SPREAD FROM THE PLAINS TO THE EAST-CENTRAL  
AND EASTERN/SOUTHEASTERN U.S. LATER NEXT WEEK AS GULF MOISTURE  
INCREASING FEEDS INTO THE SYSTEM.  
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
SINCE YESTERDAY, MODEL GUIDANCE HAS CONTINUED THE TREND OF  
INCREASING INTERACTION/PHASING BETWEEN A DEVELOPING SURFACE LOW  
OVER THE SOUTHERN PLAINS ON WEDNESDAY AND A SURGE OF COLDER AIR  
DOWN THE NORTHERN AND CENTRAL PLAINS. THE GFS TOOK THE MOST  
DECISIVE SHIFT OF TRACKING A RATHER ROBUST CYCLONE INTO THE UPPER  
MIDWEST BY THURSDAY MORNING. THE 00Z ECMWF AND, TO THE LESSER  
EXTENT, THE 00Z CMC HAVE TRENDED TOWARD A MORE ROBUST  
CYCLOGENESIS. THE 12Z ECMWF, CMC, AS WELL AS THE GFS HAVE NOW  
AGREED TO THIS SCENARIO.  
 
   
..WEATHER HIGHLIGHTS/THREATS
 
 
THE MEDIUM-RANGE PERIOD WILL BEGIN WITH A VIGOROUS UPPER LOW  
MOVING ONSHORE OVER THE SOUTHWESTERN U.S. ON MONDAY. THE HEAVIEST  
RAIN TOTALS FOR SOUTHERN CALIFORNIA WILL LIKELY BE ENHANCED BY  
HIGHER TERRAIN AND COULD CAUSE FLOODING ISSUES IF HEAVY RAIN FALLS  
OVER BURN SCAR AREAS. RAIN AND HIGHER ELEVATION SNOW WILL SPREAD  
ACROSS THE INTERMOUNTAIN WEST AND ROCKIES MONDAY AND TUESDAY. AS  
SURFACE LOW PRESSURE STRENGTHENS IN THE PLAINS AND TRACKS EAST,  
MORE WIDESPREAD RAIN AND POSSIBLY SEVERE THUNDERSTORMS ARE  
FORECAST TO DEVELOP OVER THE SOUTHERN PLAINS LATE TUESDAY AND THEN  
MOVE ACROSS THE SOUTH ON WEDNESDAY BEFORE REACHING THE SOUTHEAST  
ON THURSDAY. MEANWHILE, LIGHT RAIN AND SOME THUNDERSTORMS ARE  
ALSO EXPECTED FARTHER NORTH FROM THE CENTRAL PLAINS THROUGH THE  
MID-ATLANTIC. ON THE NORTHERN SIDE OF THE PRECIPITATION SHIELD,  
THE POTENTIAL FOR A SWATH OF HEAVY WINTRY MIX AND ACCUMULATING  
SNOWS HAVE INCREASED ACROSS THE UPPER GREAT LAKES INTO THE UPPER  
MIDWEST WEDNESDAY-THURSDAY. DEPENDING ON THE STRENGTH AND SIZE OF  
THE INTENSIFYING CYCLONE, HIGH WINDS COULD ALSO IMPACT A LARGE  
PORTION OF THE NORTHERN U.S. DURING THIS TIME FRAME. SOME WINTRY  
PRECIPITATION IS ALSO FORECAST FOR INTERIOR NEW ENGLAND LATE  
THURSDAY/EARLY FRIDAY AHEAD OF A WARM FRONT, WHILE POCKETS OF  
HEAVY RAIN IS POSSIBLE DOWN THE EAST COAST AHEAD OF A COLD FRONT.  
 
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  
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/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML  
 

 
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page