767  
FXUS02 KWBC 090655  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
155 AM EST WED FEB 9 2022  
 
VALID 12Z SAT FEB 12 2022 - 12Z WED FEB 16 2022  
   
..WEATHER PATTERN OVERVIEW
 
 
A RATHER SIGNIFICANT PATTERN CHANGE IS COMING EARLY NEXT WEEK AS A  
STRONG TROUGH, ORIGINATING OVER THE GULF OF ALASKA, DROPS  
SOUTHEASTWARD ACROSS THE WEST COAST REGION. THIS WILL ABRUPTLY  
REPLACE THE LONG-STANDING UPPER RIDGE (POSITIVE PNA PATTERN) THAT  
WILL BE OVER THE WESTERN THIRD OF THE NATION THROUGH THE END OF  
THIS WEEK AND INTO THIS WEEKEND, WHICH IS EXPECTED TO LEAD TO  
SURFACE CYCLOGENESIS BY THE MIDDLE OF NEXT ACROSS THE WESTERN HIGH  
PLAINS. THIS WILL TEND TO DISPLACE THE RIDGE AXIS FARTHER EAST  
ACROSS THE PLAINS, ALTHOUGH LESS AMPLIFIED THAN BEFORE, AND  
RESULTING IN MORE OF A QUASI-ZONAL FLOW PATTERN ACROSS MUCH OF THE  
CENTRAL AND EASTERN U.S. AS THE DEEP UPPER TROUGH OVER THE EAST  
COAST REGION LIFTS OUT BY EARLY-MID NEXT WEEK. ADDITIONALLY,  
THERE WILL LIKELY BE AN OFFSHORE LOW THAT DEVELOPS OFF THE EAST  
COAST FOR LATE SUNDAY AND THEN LIFTS NORTHEASTWARD TO NOVA SCOTIA  
AND NEWFOUNDLAND.  
   
..GUIDANCE EVALUATION/PREDICTABILITY ASSESSMENT
 
 
THE 00Z DETERMINISTIC MODEL GUIDANCE HAS COME INTO MUCH BETTER  
AGREEMENT ON THE EXPECTED SYNOPTIC SCALE EVOLUTION OF THE WESTERN  
U.S. TROUGH THAT BUILDS IN FOR EARLY NEXT WEEK. HOWEVER, THERE  
ARE STILL SOME MODEL DIFFERENCES WITH SHORTWAVE ENERGY CROSSING  
THE EASTERN U.S. THROUGH EARLY MONDAY AND ITS ROLE IN OFFSHORE  
SURFACE CYCLOGENESIS. AT THIS TIME, THIS SOUTHERN STREAM  
SHORTWAVE IS NOT EXPECTED TO PHASE WITH THE NEXT GREAT LAKES  
DISTURBANCE UNTIL AFTER THE COLD FRONT EXITS THE EAST COAST, AND  
THIS WILL LIMIT THE CHANCES OF AN OFFSHORE LOW FORMING CLOSE  
ENOUGH TO THE COAST TO CAUSE ISSUES, BUT FUTURE MODEL TRENDS WILL  
CONTINUE TO BE MONITORED, ESPECIALLY IF THE STRONGER GFS SOLUTION  
COMES TO PASS.  
 
THE WPC FRONTS/PRESSURES FORECAST WAS PRIMARILY DERIVED FROM A  
DETERMINISTIC BLEND THROUGH THE WEEKEND, AND THEN GRADUALLY  
INCREASING PERCENTAGES OF THE MEANS THROUGH EARLY NEXT WEEK. FOR  
QPF, MORE OF THE ENSEMBLE BIASED CORRECTED MODEL, ALONG WITH SOME  
OF THE CMC/GFS/ECMWF, WAS USED SINCE THE NBM APPEARS TOO LIGHT  
WITH ITS QPF ACROSS THE NORTH-CENTRAL U.S. AND LAKE EFFECT SNOW  
FOR THE WEEKEND.  
   
..WEATHER HIGHLIGHTS/THREATS
 
 
A STRONG BUT PROGRESSIVE CLIPPER TYPE LOW PRESSURE SYSTEM WILL  
CROSS SOUTHERN QUEBEC AND FAR NORTHERN NEW ENGLAND BY SATURDAY,  
WITH THE POTENTIAL FOR LIGHT TO MODERATE LAKE EFFECT SNOW ACROSS  
PORTIONS OF MICHIGAN AND UPSTATE NEW YORK IN ITS WAKE. THERE WILL  
ALSO BE BREEZY TO WINDY CONDITIONS ACROSS THE GREAT LAKES REGION  
AND THE NORTHEAST AS THIS LOW MOVES THROUGH THE REGION. ANOTHER  
CANADIAN SURFACE HIGH DROPS SOUTHWARD ACROSS THE CENTRAL U.S. AND  
DELIVERS DRY CONDITIONS TO MUCH OF THE NATION FOR THE UPCOMING  
WEEKEND. IT APPEARS LIKELY THAT A OCEANIC LOW WILL DEVELOP OFF  
THE EAST COAST BY SUNDAY EVENING, BUT IS CURRENTLY EXPECTED TO BE  
FAR ENOUGH OFFSHORE TO KEEP MOST OF THE PRECIPITATION AND WIND  
AWAY FROM LAND, ALTHOUGH SOME LIGHT SNOW IS POSSIBLE FOR THE  
DELMARVA AND COASTAL PORTIONS OF NEW ENGLAND. DEPENDING ON THE  
EVENTUAL EVOLUTION OF THE WESTERN TROUGH AND ACCOMPANYING SURFACE  
LOW, PRECIPITATION IS FORECAST TO INCREASE IN COVERAGE ACROSS  
PORTIONS OF THE ROCKIES AND PACIFIC NORTHWEST BY NEXT TUESDAY, AND  
AN INCREASE IN SHOWERS AND SOME STORMS ACROSS THE CENTRAL/SOUTHERN  
PLAINS BY WEDNESDAY AND BEYOND ALONG WITH GUSTY WINDS.  
 
IN TERMS OF TEMPERATURES, THERE WILL A BRIEF WARM-UP FOR THE EAST  
COAST ON SATURDAY, FOLLOWED BY A RETURN TO BELOW AVERAGE READINGS  
BY SUNDAY AND INTO EARLY NEXT WEEK AS THE STRONG COLD FRONT USHERS  
IN A RENEWED ROUND OF COLD WEATHER. HIGHS UP TO 20 DEGREES BELOW  
NORMAL ARE POSSIBLE FOR PORTIONS OF THE GREAT LAKES REGION THIS  
WEEKEND. IT SHOULD BE MILD ONCE AGAIN ACROSS MOST OF THE PLAINS  
FOR SUNDAY AND INTO MONDAY WITH THE WEST COAST REGION BEGINNING TO  
COOL DOWN WITH THE TROUGH BUILDING IN, AFTER ANOMALOUS WARMTH  
ACROSS PORTIONS OF CALIFORNIA THIS WEEKEND.  
 
HAMRICK  
 
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, 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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