694  
FXUS02 KWBC 011943  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
342 PM EDT WED JUN 01 2022  
 
VALID 12Z SAT JUN 04 2022 - 12Z WED JUN 08 2022  
 
...HEAVY RAIN THREAT OVER FLORIDA DUE TO TROPICAL MOISTURE INFLOW  
AND A POSSIBLY FORMING TROPICAL SYSTEM...  
 
   
..OVERVIEW
 
 
ONE NOTABLE FEATURE TO WATCH THIS WEEKEND WILL BE THE POSSIBILITY  
FOR A TROPICAL CYCLONE TO DEVELOP OVER THE NORTHWESTERN CARIBBEAN  
SEA/SOUTHEASTERN GULF OF MEXICO PARTIALLY FROM ENERGY FROM WHAT  
WAS AGATHA IN THE EASTERN PACIFIC (WHICH HAS NOW DISSIPATED OVER  
MEXICO). THE NATIONAL HURRICANE CENTER CURRENTLY SHOWS A HIGH  
CHANCE FOR A TROPICAL CYCLONE TO DEVELOP, AND ITS MOST LIKELY  
TRACK WOULD BE NORTHEASTWARD NEAR OR OVER THE FLORIDA PENINSULA  
AROUND SATURDAY AND THEN DEEPENING AS IT GOES INTO THE WESTERN  
ATLANTIC. THOUGH THE EXACT TIMING FOR DEVELOPMENT AND THE TRACK  
ARE UNCERTAIN, HEAVY RAIN WILL LIKELY IMPACT SOUTHERN FLORIDA  
REGARDLESS. FARTHER NORTH, FAIRLY ZONAL FLOW IS FORECAST OVER THE  
LOWER 48, BUT WITH SHORTWAVES AND SURFACE FRONTAL BOUNDARIES  
PROVIDING FOCI FOR THUNDERSTORMS AND POTENTIAL FOR HEAVY RAINFALL  
OVER MUCH OF THE CENTRAL CONUS.  
 
   
..MODEL GUIDANCE EVALUATION/PREFERENCES
 
 
THE LATEST GUIDANCE SUGGESTS AN AREA OF LOW PRESSURE WITHIN AN  
INVERTED TROUGH MOVING ACROSS SOUTHERN FLORIDA ON SATURDAY.  
NOTABLE DIFFERENCES OCCUR BETWEEN THE LAST SEVERAL RUNS OF THE EC  
AND GFS SUITES RESPECTIVELY. THE EC SUITE CONTINUES TO CARRY A  
SLOWER CLOSED LOW THAT INTENSIFIES FASTER THAN THE OTHER MODELS  
THROUGH THE WEEKEND. THE GFS SUITE IS FASTER AND FARTHER SOUTHEAST  
WITH THE POTENTIAL TROPICAL SURFACE LOW CENTER COMPARED TO THE 00Z  
CMC/EC AND LATEST 12Z UK. THE EC SUITE CLOSES OFF THE UPPER LOW ON  
SUNDAY DESPITE THE REST OF THE 12Z MODELS REMAINING GENERALLY OPEN  
THROUGHOUT THE SYSTEM'S LIFECYCLE.  
 
THE LATEST GUIDANCE REMAINS FAIRLY CONSISTENT WITH UPPER-LEVEL  
ZONAL FLOW, AND A SHORTWAVE RIDING ACROSS THE CENTRAL U.S. BY THE  
MIDDLE OF NEXT WEEK. THE 12Z UKMET APPEARS TO BE AN OUTLIER WITH  
RESPECT TO NEXT MONDAY'S WESTERN RIDGE, AS IT APPEARS TO AMPLIFY  
IT A BIT MORE THAN THE 12Z GFS AND 00Z DETERMINSTIC AND ENSEMBLE  
MEANS. FAIRLY GOOD AGREEMENT EXISTS IN THE SOUTHERN LAINS WITH THE  
UPPER RIDGE NEXT WEEK. THE 00Z EC APPEARS TO BE TE ONLY MODEL  
IDENTIFYING A CLOSED HIGH OVER TEXAS/NORTHERN MEXICO. THE 00Z EC  
AND 12Z GFS ARE IN GOOD AGREEMENT AS TO THE TIMING OF THE  
SHORTWAVE ENERGY ARRIVAL OVER THE CENTRAL PLAINS NEXT WEDNESDAY.  
FORTUNATELY, THE 00Z CMCE/ECE AND 12Z GEFS HANDLE THE WESTERN  
RIDGE AND ZONAL PATTERN WELL NEXT WEEK. THE 00Z AND 06Z CYCLES  
APPEAR TO CAPTURE A MEANDERING CLOSED UPPER LOW, WHICH WILL BE  
RESPONSIBLE FOR AN ATMOSPHERIC RIVER EVENT, NEAR THE PACIFIC  
NORTHWEST FAIRLY WELL.  
 
A GENERAL MODEL BLEND OF 00Z EC/UK/CMC WERE UTILIZED WITH THE 06Z  
GFS. THE 00Z UK CARRIED LESS WEIGHTING THORUGH DAY 5 AT WHICH  
POINT IT WAS REMOVED. ENSMEBLE MEANS AND THE 00Z EC AND 06Z GFS  
WERE BLENDED EQUALLY BY DAY 7.  
 
   
..SENSIBLE WEATHER/THREAT HIGHLIGHTS
 
 
REGARDLESS OF THE TIMING OF DEVELOPMENT OF A TROPICAL SYSTEM, DEEP  
TROPICAL MOISTURE IS FORECAST TO STREAM INTO SOUTHERN FLORIDA AND  
CAUSE THE POSSIBILITY FOR HEAVY RAINFALL AND FLASH FLOODING  
PARTICULARLY THROUGH SATURDAY, WITH SOME POSSIBILITY OF HEAVY RAIN  
IN CENTRAL/NORTHERN FLORIDA AS WELL. A SLIGHT RISK IS IN PLACE IN  
WPC'S EXPERIMENTAL DAY 4 EXCESSIVE RAINFALL OUTLOOK FOR THE  
SOUTHERN FLORIDA PENINSULA. GUSTY WINDS COULD ALSO BE A THREAT IF  
THE TROPICAL SYSTEM DEVELOPS, WITH STRONGER WINDS FOR A TROPICAL  
STORM THAN A TROPICAL DEPRESSION (BY DEFINITION). LINGERING  
CONVERGENCE ACROSS SOUTH FLORIDA AND THE KEYS COULD PROMOTE  
ADDITIONAL RAIN AND THUNDERSTORMS THERE THROUGH AT LEAST THE FIRST  
HALF OF NEXT WEEK.  
 
ELSEWHERE, RAIN CHANCES ARE EXPECTED TO INCREASE IN THE NORTHWEST  
INTO THE WEEKEND GIVEN THE TROUGH AXIS NEAR THE WEST COAST AND  
MOIST ONSHORE FLOW. ARI'S IN PORTIONS OF THE INTERIOR PAC NW  
SUGGEST AN ANOMALOUS LOCALLY HEAVY RAIN POSSIBLE FOR THAT REGION.  
HOWEVER, THE SOUTHWEST SHOULD REMAIN DRY AND HOT, WITH DEATH  
VALLEY EXPECTED TO MEET OR EXCEED 110F HIGH TEMPERATURES THIS  
WEEKEND INTO EARLY NEXT WEEK. FARTHER EAST, FRONTS ARE EXPECTED TO  
SPARK ROUNDS OF SHOWERS AND THUNDERSTORMS ACROSS THE CENTRAL AND  
EASTERN U.S., WITH PARTS OF THE PLAINS AND MISSISSIPPI VALLEY  
SEEING CONVECTION OVER THE WEEKEND AND EARLY NEXT WEEK AS FRONTS  
MEANDER THERE. THE AXES OF ENHANCED RAINFALL WILL BE HIGHLY  
DEPENDENT ON WHERE INDIVIDUAL BOUNDARIES SET UP, AND IT COULD TAKE  
INTO THE SHORT RANGE TO RESOLVE THESE DIFFERENCES BETWEEN MODELS  
ON PLACEMENT OF EXCESSIVE RAINFALL, BUT THE INGREDIENTS ARE  
CERTAINLY IN PLACE FOR HEAVY RAINFALL IN SOME AREAS ACROSS THE  
CENTRAL U.S. INTO EARLY NEXT WEEK. SOME SHOWERS AND THUNDERSTORMS  
COULD PRESS INTO THE EASTERN U.S. MONDAY-WEDNESDAY AHEAD OF A COLD  
FRONT.  
 
A RELATIVELY FLAT PATTERN ALOFT COMPARED TO THE SOMEWHAT MORE  
AMPLIFIED SHORT RANGE PERIOD SHOULD PRODUCE LESSER TEMPERATURE  
ANOMALIES THIS WEEKEND INTO THE FIRST HALF OF NEXT WEEK. PERIODIC  
TROUGHING IN THE NORTHERN TIER SHOULD LEAD TO SLIGHTLY BELOW  
AVERAGE TEMPERATURES BY AROUND 10F. MEANWHILE MUCH OF THE SOUTHERN  
TIER CAN EXPECT ABOVE NORMAL TEMPERATURES BY AROUND 5-10F BUT  
REACHING +15F ANOMALIES IN TEXAS EARLY NEXT WEEK. 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 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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