283  
FXUS06 KWBC 031901  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT FRI OCTOBER 03 2025  
 
6-10 DAY OUTLOOK FOR OCT 09 - 13 2025  
 
THE GEFS AND ECENS REMAIN IN GOOD AGREEMENT THAT AN OMEGA BLOCK DEVELOPS OVER  
THE NORTH PACIFIC AND WESTERN NORTH AMERICA DURING THE SECOND WEEK OF OCTOBER.  
THE HIGHLY AMPLIFIED BLOCKING PATTERN IS FORECAST TO CONSIST OF A: TROUGH OVER  
THE KAMCHATKA PENINSULA, AN ALASKAN RIDGE, AND A TROUGH ALONG THE WEST COAST.  
THE ECENS DEPICTS A POSITIVE 500-HPA HEIGHT ANOMALY OF +300 METERS NEAR THE  
ALASKA PENINSULA FOR THIS 5-DAY PERIOD. THE ECENS AND GEFS ARE IN BETTER  
AGREEMENT TODAY OVER THE CENTRAL AND EASTERN CONUS WITH A STRONG, PERSISTENT  
500-HPA RIDGE, WHILE THE CMCE IS AN OUTLIER WITH A TROUGH NEAR THE EAST COAST.  
SINCE THE ECENS HAS THE BEST DAILY CONTINUITY, THE MANUAL 500-HPA HEIGHT BLEND  
WAS WEIGHTED MOST HEAVILY WITH THIS MODEL SOLUTION.  
 
DESPITE THE EXPECTATION FOR AN AMPLIFYING 500-HPA RIDGE UPSTREAM OVER ALASKA  
WHICH CAN TYPICALLY LEAD TO AN OUTBREAK OF COLDER-THAN-NORMAL TEMPERATURES FOR  
THE LOWER 48 STATES, ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR A MAJORITY OF  
THE CONUS. THIS MILD TEMPERATURE PATTERN IS DUE TO THE LACK OF ANY SUSTAINED  
ANOMALOUS NORTHERLY FLOW AT THE MID TO HIGH LATITUDES OF NORTH AMERICA THROUGH  
MID-OCTOBER. THE LARGEST ABOVE-NORMAL TEMPERATURE PROBABILITIES (GREATER THAN  
70 PERCENT) ARE FORECAST FOR THE CENTRAL TO SOUTHERN GREAT PLAINS WHERE 5-DAY  
TEMPERATURES ARE LIKELY TO AVERAGE MORE THAN 10 DEGREES F WARMER-THAN-NORMAL.  
SINCE MODEL GUIDANCE HAS TRENDED TOWARDS A MORE AMPLIFIED 500-HPA TROUGH ALONG  
THE WEST COAST, AN INCREASED CHANCE OF BELOW-NORMAL TEMPERATURES IS FORECAST  
ACROSS THE PACIFIC NORTHWEST, CALIFORNIA, AND WESTERN NEVADA. NEAR-NORMAL  
TEMPERATURES ARE MOST LIKELY FOR PARTS OF THE NORTHEAST WHERE TEMPERATURES ARE  
PREDICTED TO TRANSITION FROM BELOW TO ABOVE FROM DAYS 6 TO 8.  
 
THE NATIONAL HURRICANE CENTER (NHC) IS MONITORING A BROAD AREA OF LOW PRESSURE  
A FEW HUNDRED MILES OFFSHORE OF SOUTHWESTERN MEXICO AND TROPICAL CYCLONE (TC)  
DEVELOPMENT IS IMMINENT. MODEL SOLUTIONS INDICATE THAT A SECOND TC COULD FORM  
JUST OFFSHORE OF SOUTHWESTERN MEXICO LATER NEXT WEEK. ALTHOUGH MODEL SPREAD  
REMAINS LARGE ON THE EXACT TRACK OF THESE POTENTIAL TCS ACROSS THE EAST  
PACIFIC, ANOMALOUS LOW TO MID-LEVEL MOISTURE IS LIKELY TO OVERSPREAD THE  
WESTERN CONUS BY DAY 6, OCTOBER 9. THIS ENHANCED MOISTURE COUPLED WITH THE  
AMPLIFIED 500-HPA TROUGH ALONG THE WEST COAST SUPPORTS AN INCREASED CHANCE OF  
ABOVE-NORMAL PRECIPITATION THROUGHOUT THE WESTERN CONUS. THE LARGEST  
ABOVE-NORMAL PRECIPITATION PROBABILITIES (EXCEEDING 60 PERCENT) ARE FORECAST  
FOR THE SOUTHWEST AND SOUTHERN CALIFORNIA. ABOVE-NORMAL PRECIPITATION IS ALSO  
FAVORED FOR THE NORTHERN TO CENTRAL GREAT PLAINS AND UPPER MISSISSIPPI VALLEY  
AS A SHORTWAVE TROUGH MAY EJECT FROM THE LONGWAVE TROUGH UPSTREAM ALONG THE  
WEST COAST. BROAD SURFACE HIGH PRESSURE, PREDICTED BY ALL THE ENSEMBLE MEAN  
SOLUTIONS, IS EXPECTED TO RESULT IN BELOW-NORMAL PRECIPITATION FROM THE  
NORTHEAST SOUTHWESTWARD TO THE LOWER MISSISSIPPI VALLEY AND SOUTHERN GREAT  
PLAINS. EASTERLY FLOW AND A BREAK IN THE SUBTROPICAL RIDGE SUPPORTS AN  
INCREASED CHANCE OF ABOVE-NORMAL PRECIPITATION ACROSS THE COASTAL SOUTHEAST,  
FLORIDA PENINSULA, AND SOUTHERN TEXAS.  
 
FORECAST CONFIDENCE IS HIGH ACROSS ALASKA WITH MODELS REMAINING CONSISTENT THAT  
A HIGHLY AMPLIFIED TROUGH CENTERED OVER THE KAMCHATKA PENINSULA LIKELY SPAWNS  
MULTIPLE SURFACE LOW PRESSURE SYSTEMS TRACKING INTO THE BERING SEA. THESE LOW  
PRESSURE SYSTEMS AND ASSOCIATED ONSHORE FLOW FAVOR ABOVE-NORMAL TEMPERATURES  
AND ABOVE-NORMAL PRECIPITATION FOR MUCH OF ALASKA. THE ONE EXCEPTION TO THE WET  
PATTERN IS OVER SOUTHEASTERN ALASKA, WHICH WOULD BE DOWNSTREAM OF THE 500-HPA  
RIDGE AXIS LEADING TO AN ELEVATED CHANCE OF BELOW-NORMAL PRECIPITATION.  
 
BASED ON THE GEFS AND ECENS, ABOVE-NORMAL TEMPERATURES AND ABOVE-NORMAL  
PRECIPITATION ARE FAVORED FOR HAWAII.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, AND 65% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 8  
 
 
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO  
GOOD AGREEMENT AMONG THE PRECIPITATION AND TEMPERATURE TOOLS THROUGHOUT MOST OF  
THE FORECAST DOMAIN.  
 
8-14 DAY OUTLOOK FOR OCT 11 - 17 2025  
 
THE PREFERRED ECENS AND GEFS ARE IN GOOD AGREEMENT WITH A 500-HPA RIDGE  
EXTENDING FROM THE GULF OF ALASKA NORTHWARD TO EASTERN MAINLAND ALASKA, A  
TROUGH ALONG THE WEST COAST OF THE CONUS, AND A BROAD MID-LEVEL RIDGE OVER THE  
CENTRAL AND EASTERN CONUS. THE CMCE WAS AN OUTLIER TODAY WITH ITS LOWER 500-HPA  
HEIGHTS ACROSS THE EAST. TOWARDS THE END OF WEEK-2, THE ECENS AND GEFS DEPICT  
THE AMPLIFIED ALASKAN RIDGE QUICKLY WEAKENING BUT FORECAST CONFIDENCE ON THIS  
TIMING IS LOW. THE BROAD 500-HPA RIDGE WITH ASSOCIATED POSITIVE HEIGHT  
ANOMALIES SUPPORT AN INCREASED CHANCE OF ABOVE-NORMAL TEMPERATURES FOR THE  
EASTERN TWO-THIRDS OF THE CONUS. ABOVE-NORMAL TEMPERATURE PROBABILITIES EXCEED  
60 PERCENT ACROSS MOST OF THE GREAT PLAINS AND MISSISSIPPI VALLEY WHICH IS  
CONSISTENT WITH THE LARGEST 500-HPA HEIGHT ANOMALIES. PROBABILITIES ARE REDUCED  
TO THE EAST OF THE APPALACHIANS SINCE RECENT MODEL RUNS HAVE FAVORED A  
TRANSIENT TROUGH DEVELOPING ALONG THE EAST COAST. DUE TO THE AMPLIFIED 500-HPA  
TROUGH ALONG THE WEST COAST, NEAR TO BELOW-NORMAL TEMPERATURES ARE FAVORED  
ACROSS THE PACIFIC NORTHWEST, GREAT BASIN, DESERT SOUTHWEST, AND CALIFORNIA.  
 
BY THE BEGINNING OF WEEK-2, ANOMALOUS LOW TO MID-LEVEL MOISTURE IS LIKELY TO BE  
WELL-ESTABLISHED THROUGHOUT THE WESTERN CONUS. THE AMPLIFIED 500-HPA TROUGH  
ALONG THE WEST COAST ALONG WITH THIS ENHANCED MOISTURE SUPPORT AN INCREASED  
CHANCE OF ABOVE-NORMAL PRECIPITATION ACROSS THAT REGION. ABOVE-NORMAL  
PRECIPITATION PROBABILITIES ARE MAXIMIZED FOR ARIZONA WHERE CLIMATOLOGY IS  
LOWER BUT ALSO BASED ON A MODEL CONSENSUS. THE ECENS FAVORS SURFACE LOW  
DEVELOPMENT ACROSS THE NORTHERN HIGH PLAINS ON DAY 8 WITH A SUBSEQUENT  
NORTHEASTWARD TRACK. THEREFORE, THE OUTLOOK LEANS SLIGHTLY ON THE WET SIDE FOR  
THE NORTHERN TO CENTRAL GREAT PLAINS AND UPPER MISSISSIPPI VALLEY. DUE TO THE  
BROAD RIDGE ALOFT AND A STORM TRACK LIKELY DISPLACED NORTHWARD OF ITS TYPICAL  
LOCATION DURING MID-OCTOBER, BELOW-NORMAL PRECIPITATION IS FAVORED FOR MUCH OF  
THE EASTERN AND SOUTH-CENTRAL CONUS. IT WAS NOTABLE THAT THE GEFS REFORECAST  
TRENDED MUCH DRIER TODAY ACROSS THE SOUTHERN GREAT PLAINS AND LOWER MISSISSIPPI  
VALLEY AND ALIGNS BETTER WITH ITS UNCALIBRATED MODEL OUTPUT. A PERSISTENT  
WEAKNESS IN THE SUBTROPICAL RIDGE SUPPORTS ELEVATED ABOVE-NORMAL PRECIPITATION  
PROBABILITIES ACROSS THE COASTAL SOUTHEAST AND FLORIDA PENINSULA. A TROPICAL  
WAVE HAS JUST MOVED WEST FROM AFRICA AND AS OF 2PM EDT ON OCTOBER 3, NHC STATES  
THAT THERE IS A 50 PERCENT CHANCE OF TC DEVELOPMENT ACROSS THE MAIN DEVELOPMENT  
REGION OF THE ATLANTIC WITHIN THE NEXT SEVEN DAYS. IN ADDITION, THERE COULD BE  
AN INCREASING CHANCE OF TC GENESIS ACROSS THE CARIBBEAN SEA LATER IN WEEK-2.  
THEREFORE, THE TROPICS WILL HAVE TO BE CLOSELY MONITORED IN SUBSEQUENT  
OUTLOOKS.  
 
SIMILAR TO THE 6-10 DAY PERIOD, SOUTHWESTERLY ONSHORE FLOW STRONGLY FAVORS  
ABOVE-NORMAL TEMPERATURES THROUGHOUT ALASKA. THE ENHANCED ONSHORE FLOW ALSO  
SUPPORTS AN INCREASED CHANCE OF ABOVE-NORMAL PRECIPITATION FOR MUCH OF ALASKA.  
DOWNSTREAM OF THE MID-LEVEL RIDGE AXIS, NEAR TO BELOW-NORMAL PRECIPITATION IS  
MORE LIKELY FOR PARTS OF SOUTHEASTERN ALASKA.  
 
BASED ON THE GEFS AND ECENS, ABOVE-NORMAL TEMPERATURES AND ABOVE-NORMAL  
PRECIPITATION ARE FAVORED FOR HAWAII. POSITIVE SEA SURFACE TEMPERATURE  
ANOMALIES ALSO SUPPORT ABOVE-NORMAL TEMPERATURES, ESPECIALLY ACROSS THE  
NORTHWESTERN ISLANDS.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, AND 65% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD  
AGREEMENT AMONG MOST OF THE TEMPERATURE AND PRECIPITATION TOOLS OFFSET BY  
UNCERTAINTY ON HOW FAST THE OMEGA BLOCK OVER THE NORTH PACIFIC AND WESTERN  
NORTH AMERICA BREAKS DOWN LATER IN WEEK-2.  
 
FORECASTER: BRAD PUGH  
 
NOTES:  
 
THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS THE SAME AS  
THAT IN THE TABLES: A-ABOVE N-NEAR NORMAL B-BELOW  
 
THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER (ORANGE,  
"A"), COLDER (BLUE, "B"), OR CLOSE TO (UNSHADED, "N"). HISTORICAL AVERAGE  
VALUES FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "F"). LABELS ON THE  
SHADED LINES GIVE THE PROBABILITY (> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  
PROBABILITY OF N IS ALWAYS < 40%.  
 
THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WETTER (GREEN,  
"A"), DRIER (TAN, "B"), OR CLOSE TO (UNSHADED, "N"). HISTORICAL MEDIAN VALUES  
FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "INCHES"). LABELS ON THE  
SHADED LINES GIVE THE PROBABILITY (> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  
PROBABILITY OF N IS ALWAYS < 40%.  
 
IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL BE A  
GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY EVEN A NORMAL  
(I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY SEASONS. IN SUCH CASES  
A FORECAST OF NEAR NORMAL IS EFFECTIVELY A FORECAST OF LITTLE OR NO  
PRECIPITATION.  
 
THE CLIMATE PREDICTION CENTER USES 1991-2020 BASE PERIOD MEANS AS REFERENCE IN  
THE CLIMATE OUTLOOKS.  
 
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON  
OCTOBER 16.  
 
ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)  
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE  
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:  
20071007 - 20040919 - 19621002 - 20080922 - 20010928  
 
ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)  
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE  
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:  
20040920 - 20071007 - 19981013 - 19621003 - 19730928  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR OCT 09 - 13 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A NRN CALIF B A  
SRN CALIF B A IDAHO A A NEVADA B A  
W MONTANA A A E MONTANA A A WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA A A S DAKOTA A A  
NEBRASKA A N KANSAS A N OKLAHOMA A B  
N TEXAS A B S TEXAS A N W TEXAS A N  
MINNESOTA A A IOWA A A MISSOURI A N  
ARKANSAS A B LOUISIANA A B WISCONSIN A A  
ILLINOIS A N MISSISSIPPI A B MICHIGAN A B  
INDIANA A B OHIO A B KENTUCKY A B  
TENNESSEE A B ALABAMA A B NEW YORK N B  
VERMONT N B NEW HAMP N B MAINE N B  
MASS N B CONN N B RHODE IS N B  
PENN A B NEW JERSEY A B W VIRGINIA A B  
MARYLAND A N DELAWARE A N VIRGINIA A N  
N CAROLINA A N S CAROLINA A N GEORGIA A N  
FL PNHDL A N FL PENIN A A AK N SLOPE A A  
AK ALEUTIAN A A AK WESTERN A A AK INT BSN A A  
AK S INT A A AK SO COAST A A AK PNHDL A B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR OCT 11 - 17 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON N A OREGON N A NRN CALIF B A  
SRN CALIF B A IDAHO N A NEVADA B A  
W MONTANA N A E MONTANA A A WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA A A S DAKOTA A A  
NEBRASKA A A KANSAS A N OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA A A IOWA A A MISSOURI A B  
ARKANSAS A B LOUISIANA A B WISCONSIN A A  
ILLINOIS A B MISSISSIPPI A B MICHIGAN A N  
INDIANA A B OHIO A B KENTUCKY A B  
TENNESSEE A B ALABAMA A B NEW YORK A N  
VERMONT A N NEW HAMP A N MAINE A N  
MASS A N CONN A N RHODE IS A N  
PENN A N NEW JERSEY A N W VIRGINIA A N  
MARYLAND A N DELAWARE A N VIRGINIA A N  
N CAROLINA A N S CAROLINA A N GEORGIA A N  
FL PNHDL A A FL PENIN A A AK N SLOPE A A  
AK ALEUTIAN A A AK WESTERN A A AK INT BSN A A  
AK S INT A A AK SO COAST A A AK PNHDL A B  
 
LEGEND  
TEMPS WITH RESPECT TO NORMAL PCPN WITH RESPECT TO MEDIAN  
A - ABOVE N - NEAR NORMAL A - ABOVE N - NEAR MEDIAN  
B - BELOW B - BELOW  
 
THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL  
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE  
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.  
 
FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS  
PMDMRD.  
 
 
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