236  
FXUS02 KWBC 021927  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
327 PM EDT THU JUN 02 2022  
 
VALID 12Z SUN JUN 05 2022 - 12Z THU JUN 09 2022  
   
..OVERVIEW
 
 
AS THE MEDIUM RANGE PERIOD BEGINS SUNDAY, A TROPICAL DISTURBANCE,  
FOR WHICH THE NATIONAL HURRICANE CENTER SHOWS A HIGH CHANCE OF  
DEVELOPMENT, SHOULD BE EAST OF THE FLORIDA PENINSULA AND PULLING  
AWAY FROM THE U.S., BUT WITH SOME SHOWERS AND STORMS POSSIBLY  
LINGERING OVER FLORIDA AND POTENTIALLY UP THE SOUTHEAST COAST  
DEPENDING ON HOW CLOSE THE LOW TRACKS TO LAND. MEANWHILE FARTHER  
NORTH, THE LOWER 48 SHOULD SEE A FAIRLY ZONAL PATTERN, BUT WITH  
SHORTWAVES AND SURFACE FRONTAL BOUNDARIES PROVIDING FOCI FOR  
THUNDERSTORMS AND POTENTIAL FOR HEAVY RAINFALL OVER MUCH OF THE  
CENTRAL U.S. AND POSSIBLY INTO THE EAST.  
 
   
..MODEL GUIDANCE EVALUATION/PREFERENCES
 
 
DETERMINISTIC MODEL GUIDANCE IS SPLIT ON THE LOCATION OF THE  
TROPICAL SYSTEM IN THE WESTERN ATLANTIC BY SUNDAY MORNING WITH THE  
00Z EC/CMC PRODUCING A LOW THAT IS CLOSER TO THE FLORIDA COAST  
THAN THE 06Z GFS AND 00Z UKMET WHICH HAVE A MORE PROGRESSIVE  
TRACK. THE EC SUITE HAS GRADUALLY WEAKENED THE ATTENDANT LOW OVER  
ITS PAST FEW RUNS WHILE THE GFS SUITE HAS REMAINED FAIRLY  
CONSISTENT.  
 
BESIDES SMALL SCALE DIFFERENCES WITH RESPECT TO THE EVOLUTION OF A  
FEW SHORTWAVES, THE GENERAL TREND OVER MUCH OF THE LOWER 48 IS FOR  
RELATIVELY ZONAL FLOW TO DOMINATE THROUGH MUCH OF THE MEDIUM RANGE  
PERIOD BEFORE A MORE AMPLIFIED PATTERN DEVELOPS LATE NEXT WEEK.  
THE LATEST 12Z EC/GFS HAVE TRENDED WEAKER WITH THE BIT OF EMBEDDED  
SHORTWAVE ENERGY FORECAST TO PROPAGATE THROUGH THE MIDDLE  
MISSISSIPPI VALLEY ON SUNDAY WHILE THE 12Z UKMET IS STRONGER WITH  
THAT PIECE OF ENERGY. THE WEAKER TREND CONTINUES WITH THE  
SHORTWAVE AS IT MOVES INTO THE OHIO VALLEY AND NORTHEAST ON  
MONDAY, WHILE THE 12Z GEFS ACTUALLY TRENDS DEEPER WITH THE  
EVOLVING SHORTWAVE. THE 00Z EC, 06Z GFS AND ENSEMBLE MEANS TEND TO  
AGREE ON THE ZONAL PATTERN ACROSS MUCH OF THE NORTHERN AND CENTRAL  
TIER OF THE COUNTRY ON TUESDAY. THERE ARE SOME TIMING AND  
INTENSITY DIFFERENCES WITH THE ARRIVAL OF A MEAN UPPER TROUGH AS  
IT ROTATES THROUGH THE ROCKIES AND PLAINS NEXT WEDNESDAY, BUT THE  
00Z EC AND 06Z GFS CONTINUE TO AGREE ON THE TIMING OF ANOTHER  
SHORTWAVE OVER PARTS OF THE MID-SOUTH. THERE'S GENERAL MODEL  
CONSENSUS ON A RIDGE BUILDING OVER THE WEST AS A TROUGH MOVES  
THROUGH THE EASTERN HALF OF THE COUNTRY NEXT THURSDAY. A BLEND OF  
THE 00Z EC/CMC AND LESSER AMOUNTS OF THE 00Z UK AND 06Z GFS WERE  
FAVORED FOR DAY 3. FOR DAY 4 THE 00Z EC, 06Z GFS AND SOME ENSEMBLE  
MEANS WERE INCORPORATED INTO A BLEND. 00Z ECE/CMCE AND 06Z GEFS  
ENSEMBLES ACCOUNTED FOR THE MAJORITY OF BLENDER WEIGHTING THROUGH  
THE REST OF THE PERIOD WITH SOME 06Z GFS AND 00Z EC SPRINKLED IN  
ALTERNATINGLY THROUH DAY 7.  
 
   
..SENSIBLE WEATHER/THREAT HIGHLIGHTS
 
 
THOUGH THE BULK OF THE EFFECTS OF THE TROPICAL DISTURBANCE WILL BE  
IN THE SHORT RANGE PERIOD, SOME SHOWERS AND STORMS COULD BE  
PRESENT ACROSS FLORIDA WITH LINGERING MOISTURE AND POSSIBLY REACH  
THE SOUTHEAST COAST. CONTINUED CONVERGENCE ACROSS SOUTH FLORIDA  
AND THE KEYS COULD PROMOTE ADDITIONAL RAIN AND THUNDERSTORMS THERE  
THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK, BUT SCATTERED IN  
NATURE. MEANWHILE A WEAK TO MODERATE ATMOSPHERIC RIVER THIS  
WEEKEND AIMED AT THE NORTHWEST U.S. WILL INCREASE PRECIPITATION  
CHANCES THERE. THIS SHOULD BE MAINLY RAIN AS SNOW LEVELS ARE  
FORECAST TO BE HIGH, WITH CHANCES FOR SNOW ONLY IN THE HIGHEST  
PEAKS OF THE CASCADES AND NORTHERN ROCKIES. PARTS OF THE CENTRAL  
U.S. CAN LIKELY EXPECT THE MOST IMPACTFUL RAIN, HOWEVER.  
MEANDERING FRONTAL BOUNDARIES WILL PROVIDE AREAS OF FOCUS FOR  
ENHANCED RAINFALL WITH CONVECTION IN A PATTERN WITH PLENTY OF  
MOISTURE. THIS LOOKS TO BE MOST LIKELY ACROSS NORTHERN/CENTRAL  
PARTS OF THE PLAINS AND INTO THE MIDDLE MISSISSIPPI VALLEY AND  
POSSIBLY THE LOWER OHIO VALLEY. BUT UNFORTUNATELY, MODELS ARE  
QUITE VARIABLE WITH THE PLACEMENT OF HEAVY RAINFALL BEYOND THAT,  
AS THE AXES OF ENHANCED RAIN WILL BE HIGHLY DEPENDENT ON WHERE  
INDIVIDUAL BOUNDARIES SET UP. THE INGREDIENTS ARE CERTAINLY IN  
PLACE FOR HEAVY RAINFALL THAT COULD CAUSE FLASH FLOODING, BUT THE  
DETAILS OF AREAS WITH THE GREATEST THREAT COULD TAKE INTO THE  
SHORT RANGE TO RESOLVE, SO HELD OFF ON ADDING ANY SLIGHT RISKS TO  
THE EXPERIMENTAL DAY 4-5 EXCESSIVE RAINFALL OUTLOOK FOR NOW AS  
THEY WOULD ALMOST CERTAINLY HAVE TO MOVE AROUND. ADDITIONALLY,  
MODELS HAVE TRENDED HEAVIER WITH RAINFALL MOVING INTO THE  
NORTHEAST AROUND MONDAY-TUESDAY AHEAD OF A COLD FRONT.  
 
EXPECT THE GENERAL PATTERN FOR TEMPERATURES NEXT WEEK TO BE COOLER  
THAN AVERAGE IN THE NORTHERN TIER AND WARMER THAN AVERAGE IN THE  
SOUTHERN TIER. THE NORTHERN PLAINS IN PARTICULAR COULD SEE HIGHS  
10-20F AND LOWS AROUND 10F BELOW AVERAGE WITH PERIODS OF TROUGHING  
ALOFT. MEANWHILE, MUCH OF THE SOUTHERN TIER IS FORECAST TO SEE  
ABOVE NORMAL TEMPERATURES BY AROUND 5-10F BUT REACHING +15F  
ANOMALIES IN TEXAS FOR THE FIRST HALF OF NEXT WEEK GIVEN AN UPPER  
HIGH ALOFT. THE WEST COAST SHOULD BE A BIT COOLER THAN NORMAL OVER  
THE WEEKEND UNDER THE TROUGHING INFLUENCE, BUT MODERATING AND  
WARMING TO ABOVE NORMAL IN CALIFORNIA AND INTO THE GREAT BASIN AND  
SOUTHWEST BY AROUND MIDWEEK.  
 
TATE/KEBEDE  
 
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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