609  
FXUS02 KWBC 190602  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
101 AM EST SUN JAN 19 2020  
 
VALID 12Z WED JAN 22 2020 - 12Z SUN JAN 26 2020  
   
..OVERVIEW
 
 
A DEVELOPING SYSTEM IN THE SOUTHERN PLAINS WILL SPREAD MODEST TO  
PERHAPS LOCALLY HEAVY RAINFALL FROM THE LOWER MISSISSIPPI VALLEY  
NORTHEASTWARD NEXT THU-SUN. IN THE PACIFIC NORTHWEST, A STEADY  
STREAM OF SYSTEMS WILL SUBJECT SOME CITIES TO SOME SOGGINESS.  
OVERALL, A WARMING TREND OVER MOST OF THE CONUS IS EXPECTED.  
   
..GUIDANCE/PREDICTABILITY ASSESSMENT
 
 
THE MODELS/ENSEMBLES WERE IN GENERALLY GOOD SYNOPTIC AGREEMENT IN  
SHOWING A PROGRESSIVE AND MODESTLY AMPLIFIED LONGWAVE FLOW  
PATTERN. A BLEND AMONG THE GFS/ECMWF/CANADIAN FORMED A GOOD  
CLUSTER AROUND THE ENSEMBLE CONSENSUS WHICH STILL SHOWS FAIRLY  
TYPICAL SPREAD. THE 12Z CANADIAN WAS MOSTLY IN BETWEEN THE GFS AND  
ECMWF AND CLOSER TO THE BEST ENSEMBLE CLUSTERING, BUT NEITHER  
OTHER SCENARIO WAS CONSIDERED IMPROBABLE. THIS WOULD TAKE THE  
SOUTHERN SYSTEM NORTHEASTWARD TOWARD THE MIDWEST WITH A JUMP  
ACROSS THE APPALACHIANS THROUGH THE MID-ATLANTIC NEXT WEEKEND. OFF  
THE WEST COAST, ENSEMBLES HAVE TRENDED TOWARD DEEPER TROUGHING  
NEXT WEEKEND AT THE EXPENSE OF THE LEADING SYSTEMS EAST OF THE  
ROCKIES.  
 
   
..WEATHER/HAZARD HIGHLIGHTS
 
 
DESPITE WHAT IS NORMALLY JUST ABOUT THE COLDEST TIME OF THE YEAR,  
TEMPERATURES WILL TREND TOWARD ABOVE AVERAGE NEARLY CONUS-WIDE BY  
THE END OF THE WEEK INTO NEXT WEEKEND. HIGHEST ANOMALIES WILL LIE  
ASTRIDE THE CANADIAN BORDER WITH NEAR TO SLIGHTLY ABOVE AVERAGE  
TEMPERATURES NEAR THE GULF COAST.  
 
PRECIPITATION WILL BE NON-CONTINUOUS BUT QUITE REPETITIVE IN THE  
NORTHWEST AS SEVERAL SYSTEMS PUSH THROUGH. THE GENERALLY MILD FLOW  
WILL KEEP SNOW LEVELS A BIT HIGHER TOO. FARTHER EAST, RAINFALL  
WILL EXPAND OVER TEXAS TO POINTS EASTWARD/NORTHEASTWARD WITH HELP  
FROM LEFTOVER MID/HIGH-LEVEL MOISTURE ACROSS THE EASTERN  
PACIFIC/BAJA MEXICO. GULF INFLOW WILL HELP REALIZE MODEST RAINFALL  
TOTALS ALONG THE NW GULF COAST BUT WITH CONTINUED UNCERTAINTY TO  
ITS NORTHWARD EXTENT. SOME AMOUNTS COULD BE LOCALLY HEAVY. THE  
SYSTEM WILL LIKELY HAVE SOME WINTRY WEATHER ON ITS NORTHERN SIDE  
FROM THE CENTRAL PLAINS TO THE GREAT LAKES BUT WITH AMOUNTS  
CONTINGENT ON THE PRECIPITATION STRUCTURE AND SYSTEM EVOLUTION.  
 
FRACASSO  
 
ADDITIONAL 3-7 DAY HAZARDS INFORMATION CAN BE FOUND ON THE WPC  
MEDIUM RANGE HAZARDS CHART AT:  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP  
 
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,  
QUANTITATIVE PRECIPITATION, 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/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML  
 

 
 
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