053  
FXUS02 KWBC 200647  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
246 AM EDT TUE SEP 20 2022  
 
VALID 12Z FRI SEP 23 2022 - 12Z TUE SEP 27 2022  
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
MODEL AND ENSEMBLE SOLUTIONS ARE WELL CLUSTERED THROUGH MEDIUM  
RANGE TIME SCALES OVER THE LOWER 48, BOLSTERING FORECAST  
CONFIDENCE DESPITE SOME LINGERING LOCAL EMBEDDED SYSTEM  
TIMING/STRENGTH DIFFERENCES. THE WPC MEDIUM RANGE PRODUCT SUITE  
WAS MAINLY DERIVED FROM A BLEND OF THE 18 UTC GFS, 12 UTC  
ECMWF/UKMET/CANADIAN AND 01 UTC NATIONAL BLEND OF MODELS  
FRIDAY-SUNDAY, INCREASINGLY GRAVITATING TO THE COMPATIBLE  
GEFS/ECMWF ENSEMBLE MEANS INTO EARLY NEXT WEEK. OVERALL, GUIDANCE  
DIFFERENCES SEEM WELL MITIGATED BY THE COMPOSITE BLENDING PROCESS  
CONSISTENT WITH A PATTERN WITH ABOVE NORMAL PREDICTABILITY. WPC  
PRODUCT CONTINUITY IS WELL MAINTAINED IN THIS MANNER AND REMAINS  
IN LINE WITH LATEST 00 UTC MODELS AND ENSEMBLES.  
   
..PATTERN OVERVIEW AND WEATHER/HAZARDS HIGHLIGHTS
 
 
AMPLE COOL CANADIAN HIGH PRESSURE WILL SETTLE ACROSS MUCH OF THE  
CENTRAL TO EASTERN U.S. FRIDAY INTO THE WEEKEND IN THE WAKE OF A  
LEAD SYSTEM/COLD FRONT. THE LINGERING FRONT MAY FOCUS SOME SHOWERS  
ACROSS FLORIDA.  
MEANWHILE UPSTREAM, INITIALLY AMPLIFIED UPPER TROUGH EJECTION OUT  
FROM THE WEST AND SURFACE SYSTEM TRANSLATION SHOULD FOCUS MODEST  
CONVECTION COVERAGE OVER THE NORTH-CENTRAL U.S/MIDWEST BY  
FRIDAY/SATURDAY. A WARMING UPPER RIDGE WITH UPWARDS TO 10F+ ABOVE  
NORMAL MAXIMUM TEMPERATURE ANOMALIES IS EXPECTED TO BUILD BACK  
OVER THE DRIER WEST IN THE WAKE OF THIS SYSTEM SUNDAY INTO EARLY  
NEXT WEEK. THIS RIDGE AMPLIFICATION SHOULD FAVOR THE DOWNSTREAM  
DIGGING OF REINFORCING NORTHERN STREAM SHORTWAVE ENERGIES/FRONTAL  
SYSTEMS THAT IS FORECAST TO REJUVENATE LEAD CONVECTIVE RAINFALL  
POTENTIAL THAT MAY OFFER SOME LOCAL RUNOFF ISSUES FROM THE GREAT  
LAKES/OHIO VALLEY/APPALACHIANS SUNDAY THROUGH THE  
NORTHEAST/MID-ATLANTIC MONDAY. THE TRAILING FRONTAL PUSH ACROSS  
THE SOUTH EARLY NEXT WEEK SEEMS TO ONLY OFFER ISOLATED SHOWER  
ACTIVITY, BUT WILL USHER IN ANOTHER REFRESHING SURGE OF CANADIAN  
HIGH PRESSURE DOWN ACROSS MUCH OF THE CENTRAL-EASTERN U.S..  
 
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, EXPERIMENTAL EXCESSIVE RAINFALL  
OUTLOOK, WINTER WEATHER OUTLOOK PROBABILITIES AND HEAT INDICES ARE  
AT:  
 
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  
 

 
 

 
 
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