895  
FXUS02 KWBC 020657  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
257 AM EDT TUE JUL 2 2024  
 
VALID 12Z FRI JUL 5 2024 - 12Z TUE JUL 9 2024  
 
***MAJOR HEATWAVE EXPECTED FOR THE LOWER ELEVATIONS OF CALIFORNIA  
AND THE DESERT SOUTHWEST NEXT WEEK, AND BERYL EVENTUALLY HEADED  
FOR THE WESTERN GULF***  
   
..OVERVIEW
 
 
THE MAIN THING MAKING WEATHER HEADLINES DURING THIS FORECAST PERIOD  
WILL THE INTENSE AND PROLONGED HEATWAVE ENCOMPASSING MUCH OF  
CALIFORNIA AND EXTENDING INTO THE LOWER ELEVATIONS OF THE DESERT  
SOUTHWEST. HOT AND HUMID CONDITIONS WILL ALSO CONTINUE FOR MUCH OF  
THE SOUTHERN STATES AND EXTENDING TO THE EAST COAST. A LOW PRESSURE  
SYSTEM IS FORECAST TO CROSS THE UPPER MIDWEST AND BRING A ROUND OF  
HEAVY RAIN AND STORMS TO THE GREAT LAKES ON FRIDAY, AND ADDITIONAL  
STORMS NEAR THE TRAILING FRONTAL BOUNDARY ACROSS PORTIONS OF THE  
SOUTHERN PLAINS AND EXTENDING EAST TO THE OHIO VALLEY AND THE MID-  
ATLANTIC REGION. THE TRACK OF HURRICANE BERYL IS EXPECTED TO ENTER  
THE BAY OF CAMPECHE AND THE WESTERN GULF BY SATURDAY WITH RAINFALL  
CHANCES INCREASING FOR PORTIONS OF SOUTHERN TEXAS BY THE WEEKEND.  
 
   
..GUIDANCE/PREDICTABILITY ASSESSMENT
 
 
THE 00Z MODEL GUIDANCE SUITE INDICATES GOOD OVERALL SYNOPTIC SCALE  
AGREEMENT ACROSS THE CONTINENTAL U.S. TO CLOSE OUT THE WORK WEEK,  
AND BETTER AGREEMENT ON THE MASSIVE UPPER RIDGE BUILDING OVER THE  
WEST COAST, POTENTIALLY REACHING 600DM. THE GUIDANCE SUGGESTS THIS  
RIDGE SHOULD SLOWLY MOVE EAST OVER THE SOUTHERN INTERMOUNTAIN WEST  
BY NEXT TUESDAY/WEDNESDAY. MEANWHILE, A GENERAL TROUGH AXIS  
SITUATED OVER THE NORTH-CENTRAL U.S. SHOULD BE ANCHORED IN PLACE BY  
ANOTHER RIDGE AXIS OVER THE WESTERN ATLANTIC OCEAN. A GENERAL  
DETERMINISTIC MODEL BLEND SUFFICED AS A GOOD STARTING POINT IN THE  
FORECAST PROCESS FOR FRIDAY/SATURDAY, AND THEN INCREASED THE  
ENSEMBLE MEANS TO ABOUT 40% BY NEXT TUESDAY.  
 
THE LATEST FORECAST FROM THE NATIONAL HURRICANE CENTER HAS  
HURRICANE BERYL REACHING THE YUCATAN PENINSULA AROUND FRIDAY  
MORNING, AND THEN EMERGING OVER THE BAY OF CAMPECHE BY SATURDAY,  
FOLLOWED BY MORE OF A NORTHWESTWARD TURN. THERE HAS BEEN A RECENT  
TREND IN THE GUIDANCE FOR A MORE NORTHWARD TRACK BY THE TIME IT  
ENTERS THE WESTERN GULF, WHICH COULD RESULT IN DETERIORATING  
WEATHER CONDITIONS FOR SOUTHERN TEXAS. THE TROUGH OVER THE CENTRAL  
U.S. WILL BE A BIG FACTOR IN DETERMINING THE EVENTUAL TRACK. BERYL'S  
TRACK WILL CONTINUE TO BE CLOSELY MONITORED OVER THE NEXT SEVERAL  
DAYS, AND THE NHC HAS ADDITIONAL INFORMATION PERTAINING TO THIS.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
HEAVY RAIN WITH EMBEDDED THUNDERSTORMS ARE LIKELY TO CONTINUE  
ACROSS NORTHERN WISCONSIN AND INTO THE UPPER PENINSULA OF MICHIGAN  
GOING INTO FRIDAY AS THE DEVELOPING SURFACE LOW TRACKS ACROSS THE  
REGION, AND A MARGINAL RISK WILL REMAIN THERE FOR THE DAY 4 PERIOD.  
FARTHER SOUTH, A CORRIDOR OF HEAVY SHOWERS AND STORMS IS LIKELY  
FROM NORTHERN TEXAS TO THE TENNESSEE RIVER VALLEY, AND A MARGINAL  
RISK AREA IS ALSO VALID HERE FOR FRIDAY. THIS HAS TRENDED MORE  
SOUTHWARD COMPARED TO YESTERDAY'S FORECAST. LOOKING AHEAD TO  
SATURDAY, THERE IS ENOUGH OF A MODEL SIGNAL TO SUPPORT A PLANNED  
MARGINAL RISK AREA FOR PORTIONS OF THE MID-ATLANTIC, WHERE SOME  
SLOW MOVING THUNDERSTORMS ARE LIKELY TO DEVELOP IN THE VICINITY OF  
A SLOW MOVING FRONTAL BOUNDARY. SOME OF THE OUTER RAIN BANDS OF  
BERYL COULD BE APPROACHING SOUTHERN TEXAS BY LATE SATURDAY AND  
INTO EARLY SUNDAY, BUT GENERALLY NOT EXPECTED TO BE HEAVY ENOUGH BY  
THAT TIME TO WARRANT ANY RISK AREAS. THIS COULD CHANGE GOING INTO  
SUNDAY, ESPECIALLY IF THE TRACK TRENDS FARTHER NORTH IN LATER  
FORECAST UPDATES, SO STAY TUNED!  
 
IT WILL CONTINUE TO REMAIN HOT AND HUMID ACROSS TEXAS AND EXTENDING  
EASTWARD ACROSS THE DEEP SOUTH AND INTO THE SOUTHEAST FOR THE END  
OF THE WEEK AND INTO NEXT WEEKEND, WITH HIGHS IN THE MIDDLE TO  
UPPER 90S AND DEWPOINTS WELL INTO THE 70S. IT WILL ALSO BE GETTING  
VERY HOT FOR THE INLAND LOWER ELEVATIONS OF CALIFORNIA AND INTO THE  
ARIZONA DESERTS WITH WIDESPREAD 105-115 DEGREE READINGS LIKELY,  
AND LOCALLY HIGHER FOR THE NORMALLY WARMER LOCATIONS. DAILY  
TEMPERATURES RECORDS MAY BE TIED OR BROKEN IN MANY CASES. THE HEAT  
LIKELY EXPANDS ACROSS INLAND PORTIONS OF WASHINGTON, OREGON, AND  
MUCH OF THE INTERMOUNTAIN WEST BY THE SUNDAY-TUESDAY TIME PERIOD,  
WITH 100+ DEGREE HIGHS LIKELY FOR THE LOWER VALLEY LOCATIONS.  
 
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 FORECAST (QPF), EXCESSIVE RAINFALL  
OUTLOOK (ERO), WINTER WEATHER OUTLOOK (WWO) PROBABILITIES, HEAT  
INDICES, AND KEY MESSAGES CAN BE ACCESSED FROM:  
 
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  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=OVW  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page