492  
FXUS02 KWBC 221806  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
205 PM EDT WED JUN 22 2022  
 
VALID 12Z SAT JUN 25 2022 - 12Z WED JUN 29 2022  
 
...EXCESSIVE HEAT THREATS FOR THE SOUTH AND NORTHWEST THIS WEEKEND  
WILL MODERATE NEXT WEEK...  
 
   
..OVERVIEW
 
 
THE BROAD UPPER LEVEL RIDGING OVER THE SOUTHERN U.S. WILL FINALLY  
BEGIN TO WEAKEN AND BREAK DOWN THIS WEEKEND AS A SHORTWAVE THROUGH  
THE NORTHERN TIER TO THE NORTH BEGINS TO AMPLIFY AS IT REACHES THE  
GREAT LAKES AND ESPECIALLY THE NORTHEAST EARLY NEXT WEEK.  
MEANWHILE, MONSOONAL MOISTURE WILL CONTINUE TO PERSIST INTO THE  
FOUR CORNERS REGION THROUGH MUCH OF THE PERIOD WITH POTENTIAL FOR  
HEAVIER TO EXCESSIVE RAINS ALONG THE SOUTHERN HALF OF THE ROCKIES  
THIS WEEKEND WITH THE ARRIVAL OF A SURFACE FRONT AND TRAILING LOW  
LEVEL UPSLOPE FLOW. THE PATTERN LOOKS TO BECOME MORE AMPLIFIED BY  
EARLY NEXT WEEK ACROSS THE CONUS WITH TROUGHING IN THE EAST AND  
THE ARRIVAL OF A CLOSED UPPER LOW TOWARDS THE WEST COAST, AND  
RIDGING BUILDING IN BETWEEN OVER A WARMED INTERIOR WEST.  
 
   
..GUIDANCE/PREDICTABILITY EVALUATION
 
 
THE WPC MEDIUM RANGE PRODUCT SUITE WAS PRIMARILY DERIVED FROM A  
COMPOSITE BLEND OF WELL CLUSTERED MODEL GUIDANCE OF THE 06 UTC  
GFS, 00 UTC ECMWF/UKMET/CANADIAN AND 13 UTC NATIONAL BLEND OF  
MODELS DAYS 3-5 (SATURDAY-MONDAY). GUIDANCE SOLUTIONS REMAIN WELL  
CLUSTERED AT MID-LARGER SCALES INTO DAYS 6/7, BUT THE GFS/ECMWF  
AND GEFS/ECMWF ENSEMBLE MEANS SEEM TO OFFER THE BEST COMBINATION  
WITH AGREED UPON EMBEDDED FEATURES AT THESE LONGER TIME FRAMES AND  
MESH SEEMINGLY WELL WITH THE NBM AS WELL IN A CONTINUING PATTERN  
WITH ABOVE NORMAL PREDICTABILITY.  
 
   
..SENSIBLE WEATHER/THREAT HIGHLIGHTS
 
 
ANOMALOUSLY HIGH MONSOONAL MOISTURE FOR THIS TIME OF YEAR, LIKELY  
TIED AT LEAST IN PART TO AN EASTERN PACIFIC TROPICAL SYSTEM, WILL  
CONTINUE STREAMING INTO THE FOUR CORNERS STATES INTO EARLY NEXT  
WEEK. LOCALLY HEAVY TO EXCESSIVE RAINFALL IS POSSIBLE,  
PARTICULARLY OVER SENSITIVE BURN SCAR AREAS AND CONSIDERING THE  
MULTIPLE DAY REPEATING NATURE OF THIS ACTIVITY. RAINFALL MAY TREND  
HEAVIER OVER PARTS OF COLORADO/NEW MEXICO BY THE WEEKEND AS A  
FRONT DROPPING SOUTH THROUGH THE REGION AND TRAILING LOW LEVEL  
UPSLOPE FLOW COULD INTERACT WITH THE MOISTURE ALREADY IN PLACE.  
MODELS SHOWED ENOUGH AGREEMENT FOR THE INCLUSION OF A SLIGHT RISK  
IN NORTHEAST NEW MEXICO ON THE EXPERIMENTAL DAY 4 AND DAY 5 ERO.  
MOISTURE WILL CONTINUE ROUNDING THE TOP OF THE RIDGE THROUGH THE  
PLAINS, WHILE INTERACTING WITH A COLD FRONT THROUGH THE UPPER  
MIDWEST, WHERE SOME INCREASED THREAT FOR ORGANIZED SHOWERS IS  
POSSIBLE. THE COLD FRONT SHOULD BE FAIRLY PROGRESSIVE THROUGH THE  
MIDWEST AND INTO THE EAST THIS WEEKEND, BUT WITH ENOUGH MOISTURE  
AND INSTABILITY ALONG THE BOUNDARY PRESENT, SOME LOCALLY HIGHER  
TOTALS SEEM LIKELY, SPECIFIC AMOUNTS AND LOCATIONS THO REMAIN  
HIGHLY DEPENDENT ON STILL UNCERTAIN TIMING OF THE FRONT. A FRONT  
SETTLING ACROSS THE SOUTHEAST INTO SATURDAY SHOULD ALSO BRING A  
PERIOD OF ENHANCED RAINFALL TO PARTS OF THE FLORIDA PENINSULA.  
 
EXCESSIVE HEAT ACROSS THE SOUTHERN U.S. SHOULD FINALLY BEGIN TO  
WANE SOME, ESPECIALLY IN PARTS OF THE SOUTHEAST, BY THIS WEEKEND.  
ANOMALIES AVERAGING 10 TO 15 DEGREES ABOVE NORMAL WILL CONTINUE  
ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHERN PLAINS WITH  
ANOTHER FEW DAYS OF RECORDS BOTH FOR DAYTIME HIGHS AND WARM  
OVERNIGHT MINS. BY EARLY NEXT WEEK, TEMPERATURES ALL ACROSS THE  
SOUTH SHOULD FINALLY TREND BACK TOWARDS NORMAL. RELATIVELY COOLER  
TEMPERATURES WITH WELL BELOW NORMAL HIGHS ARE LIKELY TO BE MOST  
PERSISTENT OVER PARTS OF NEW MEXICO AND COLORADO GIVEN THE  
MONSOONAL CLOUDS AND RAIN COVERAGE. THE NORTHERN HIGH PLAINS MAY  
ALSO SEE COOL HIGHS FROM SATURDAY INTO SUNDAY. THE WEST COAST  
STATES SHOULD SEE HIGHS 5-15F ABOVE AVERAGE THROUGH ABOUT TUESDAY  
AS UPPER RIDGING MOVES THROUGH THE REGION, WITH THE INTERIOR  
NORTHWESTERN U.S. HAVING AN EXCESSIVE HEAT THREAT THIS WEEKEND IN  
PARTICULAR.  
 
SANTORELLI/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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