575  
FXUS02 KWBC 030828  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
428 AM EDT FRI OCT 3 2025  
 
VALID 12Z MON OCT 06 2025 - 12Z FRI OCT 10 2025  
 
   
..GENERAL OVERVIEW
 
 
UPPER RIDGING OVER THE EASTERN SEABOARD WILL SHUNT SOUTH AND SHIFT  
WEST OVER THE GULF COAST MONDAY THROUGH TUESDAY WHERE IT WILL  
PERSIST THROUGH NEXT WEEK. MEANWHILE A MORE TRANSIENT UPPER PATTERN  
CONTINUES OVER THE CENTRAL/NORTHERN STATES WITH A DEEP TROUGH  
SWINGING THROUGH THE GREAT LAKES TUESDAY INTO WEDNESDAY. A COLD  
FRONT A CANADIAN SURFACE HIGH PRESSURE FOLLOWS THIS TROUGH WITH  
COOLER THAN NORMAL TEMPERATURES TRACKING FROM THE NORTHERN PLAINS  
TUESDAY TO THE NORTHEAST BY LATE WEEK. FARTHER SOUTH, TROPICAL  
MOISTURE INTERACTING WITH A LINGERING STATIONARY FRONT MAY PRODUCE  
HEAVY THUNDERSTORMS OVER FLORIDA, GEORGIA, AND INTO SOUTH CAROLINA  
MONDAY. FINALLY, DEEP UPPER TROUGHING LOOKS TO AMPLIFY ALONG/OFF  
THE PACIFIC NORTHWEST COAST LATER NEXT WEEK.  
 
   
..GUIDANCE/PREDICTABILITY ASSESSMENT
 
 
A MAJOR SHIFT IN THE 00Z GUIDANCE IS NOTED OVER PRIOR RUNS WITH  
STRONGER RIDGING OVER FLORIDA MONDAY INTO TUESDAY WITH MARKEDLY  
LESS QPF IN SC/GA. ALSO THE 00Z ECMWF IS MUCH SLOWER WITH TROPICAL  
ACTIVITY/QPF INTO THE DESERT SOUTHWEST LATER NEXT WEEK COMPARED TO  
THE 12Z RUN. ALSO, THE LATE WEEK TROUGHING OVER THE NORTHWEST LOOKS  
TO BE SLOWER AND FARTHER WEST/OFFSHORE IN THE 00Z GUIDANCE COMPARED  
TO THE PREVIOUS. QUITE REMARKABLE HOW STARK THE DIFFERENCES ARE  
WITH DAYS 4/5 QPF IN THE SOUTHEAST AND DAYS 6/7 IN THE SOUTHWEST.  
HOWEVER, MUCH OF THIS WAS NOTED IN THE 12Z/18Z EC-AIFS RUNS WHICH  
ONCE AGAIN SEEMS TO BE LEADING GLOBAL DETERMINISTIC GUIDANCE IN  
OVERALL SYNOPTIC PATTERN RECOGNITION. BY THE WAY THE UKMET IS NO  
LONGER AVAILABLE FOR USAGE IN OUR BLENDING PROCESS, SO THE WPC  
FORECAST RELIED HEAVILY ON THE EC/GFS WITH SOME CMC DAYS 3-5 BEFORE  
GOING HEAVIER ON THE ECENS MEANS FOR 6/7.  
 
   
..WEATHER/HAZARDS HIGHLIGHTS
 
 
DESPITE 00Z GUIDANCE HAVING MARKED REDUCTIONS IN SOUTHEAST QPF  
MONDAY/TUESDAY, THE NEW DAY 4 ERO REMAINS MARGINAL WITH SOME SHIFTS  
SOUTH AND INLAND. THE MOISTURE ANOMALIES ARE NOW GENERALLY FOCUSED  
OVER THE FL PENINSULA INTO GA/AL, SO THIS ARE WILL NEED CONTINUED  
MONITORING FOR EXCESSIVE RAIN.  
 
A COLD FRONT AHEAD OF A POWERFUL TROUGH PIVOTS OVER THE CENTRAL  
PLAINS INTO THE MIDWEST MONDAY. THE RISK OF REPEATING HEAVY RAIN  
WARRANTS MAINTENANCE OF A MARGINAL RISK FOR DAY 4 FROM CENTRAL KS  
THROUGH THE IL/WI BORDER. THE AREA WAS SHIFTED SOUTH A BIT BASED ON  
00Z CONSENSUS TRENDING MORE TOWARD THE GREATER INSTABILITY TO THE  
SOUTH.  
 
MOISTURE ANOMALIES INCREASE OVER NEW MEXICO TUESDAY FROM CONTINUED  
SURGES OF MOISTURE FROM THE WESTERN GULF ONTO A FRONTAL WAVE THAT  
IS STALLED OVER NORTHERN NM. INTRODUCED A DAY 5 MARGINAL RISK FOR  
MUCH OF NM. CONSIDERED A SLIGHT RISK, BUT GIVEN THE NOTABLE RUN-  
TO-RUN CHANGES IN GUIDANCE A MARGINAL WILL SUFFICE FOR NOW.  
 
TEMPERATURES WILL BE BELOW NORMAL UNDER TROUGHING OVER THE  
INTERMOUNTAIN WEST MONDAY WITH THAT COOLER TREND SHIFTING EAST  
WITH A COLD FRONT OVER THE NORTHERN PLAINS TUESDAY, THE MIDWEST  
WEDNESDAY, AND THE EASTERN SEABOARD FOR THURSDAY/FRIDAY. MEANWHILE,  
RIDGING OVER THE GULF COAST WILL MAINTAIN ABOVE NORMAL TEMPERATURES  
OVER TEXAS AND LOUISIANA THROUGH NEXT WEEK.  
 
JACKSON  
 
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  
 

 
 
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