415  
FXUS06 KWBC 102001  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST WED DECEMBER 10 2025  
 
6-10 DAY OUTLOOK FOR DEC 16 - 20 2025  
 
THE 0Z ECMWF, GEFS, AND CANADIAN ENSEMBLE MEANS PREDICT AN AMPLIFIED  
CIRCULATION PATTERN OVER NORTH AMERICA AND SURROUNDING REGIONS DURING THE 6–10  
DAY PERIOD. ALL MODELS PREDICT AN AMPLIFIED RIDGE AND A STRONG POSITIVE 500-HPA  
HEIGHT ANOMALY CENTERED TO THE WEST OF MAINLAND ALASKA. DOWNSTREAM, MODELS  
PREDICT A POSITIVELY TILTED TROUGH AND NEGATIVE 500-HPA HEIGHT ANOMALIES OVER  
EASTERN AND CENTRAL MAINLAND ALASKA, SOUTHEAST ALASKA, THE GULF OF ALASKA, AND  
PARTS OF THE NORTHWESTERN CONTIGUOUS U.S. (CONUS). ENSEMBLE MEANS PREDICT A  
RIDGE AND ASSOCIATED POSITIVE 500-HPA HEIGHT ANOMALIES OVER MOST OF THE CONUS  
AT THE START OF THE 6–10 DAY PERIOD THAT EXPANDS EASTWARD OVER TIME. A TROUGH  
AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES OVER MAINE AT THE START OF THE  
PERIOD ARE PREDICTED TO RAPIDLY PROGRESS NORTHEASTWARD AS MID-LEVEL HEIGHTS  
RISE. NEAR TO BELOW NORMAL 500-HPA HEIGHTS ARE PREDICTED ACROSS HAWAII DURING  
THE 6–10 DAY PERIOD.  
 
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN ALEUTIAN ISLANDS UNDER  
PREDICTED POSITIVE 500-HPA HEIGHT ANOMALIES. NEAR TO BELOW NORMAL TEMPERATURES  
ARE LIKELY FOR MAINLAND ALASKA UNDER ANOMALOUS NORTHERLY MID-LEVEL FLOW. BELOW  
NORMAL TEMPERATURES ARE LIKELY FOR SOUTHEAST ALASKA UNDER A PREDICTED TROUGH.  
NEAR TO ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE CONUS (EXCEPT FOR  
PARTS OF MAINE, WHERE BELOW NORMAL TEMPERATURES ARE FAVORED UNDER BELOW-NORMAL  
500-HPA HEIGHTS) DUE TO A PERSISTENT RIDGE AND ABOVE NORMAL 500-HPA HEIGHTS.  
PROBABILITIES EXCEED 90 PERCENT OVER PARTS OF THE FOUR CORNERS REGION,  
SUPPORTED BY MOST OF THE DYNAMICAL TEMPERATURE FORECAST TOOLS. ABOVE NORMAL  
TEMPERATURES ARE VERY LIKELY ACROSS HAWAII IN THE 6–10 DAY PERIOD, CONSISTENT  
WITH THE TEMPERATURE CONSOLIDATION.  
 
BELOW NORMAL PRECIPITATION IS LIKELY FOR THE ALEUTIAN ISLANDS AND SOUTHERN  
MAINLAND ALASKA UNDER AND AHEAD OF THE POSITIVE 500-HPA ANOMALY CENTER. NEAR TO  
ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR NORTHERN MAINLAND ALASKA,  
CONSISTENT WITH ALL ENSEMBLE MODEL PRECIPITATION FORECASTS. ABOVE NORMAL  
PRECIPITATION IS VERY LIKELY FOR THE PACIFIC NORTHWEST AND ACROSS THE NORTHERN  
ROCKIES, AHEAD OF THE TROUGH OVER THE NORTH PACIFIC AND CONSISTENT WITH ALL  
ENSEMBLE MODEL PRECIPITATION TOOLS. ENHANCED PROBABILITIES FOR ABOVE NORMAL  
PRECIPITATION EXTEND AS FAR SOUTH AS CENTRAL CALIFORNIA, CONSISTENT WITH  
TELECONNECTIONS TO THE STRONG POSITIVE 500-HPA HEIGHT ANOMALY CENTER TO THE  
WEST OF ALASKA. ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS THE NORTHERN TIER  
OF THE WESTERN CONUS INTO PARTS OF THE NORTHERN PLAINS, MUCH OF THE GREAT LAKES  
REGION, AND PARTS OF THE NORTHEAST UNDER STRONG WESTERLY MID-LEVEL FLOW. BELOW  
NORMAL PRECIPITATION IS FAVORED OVER THE SOUTHWESTERN CONUS AND THE CENTRAL  
PLAINS UNDER THE PREDICTED RIDGE AND POSITIVE 500-HPA HEIGHT ANOMALIES. BELOW  
NORMAL PRECIPITATION IS SLIGHTLY FAVORED OVER PORTIONS OF THE MIDDLE ATLANTIC  
AND THE SOUTHEAST, CONSISTENT WITH MOST MODEL PRECIPITATION TOOLS DESPITE  
UNCERTAINTY IN A CHANGING PATTERN. PROBABILITIES FOR ABOVE NORMAL PRECIPITATION  
ARE ENHANCED OVER SOUTHEASTERN AREAS OF TEXAS AND THE SOUTHERN FLORIDA  
PENINSULA, WHERE MODEL FORECASTS ARE IN AGREEMENT. NEAR TO ABOVE NORMAL  
PRECIPITATION IS FAVORED FOR MOST OF THE HAWAIIAN ISLANDS, CONSISTENT WITH  
MODEL FORECASTS.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 8, AND 30% OF TODAY'S 0Z CANADIAN 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 ENSEMBLE MODEL FORECASTS, OFFSET BY SOME DIFFERENCES AMONG  
TEMPERATURE AND PRECIPITATION FORECAST TOOLS FOR CERTAIN AREAS.  
 
8-14 DAY OUTLOOK FOR DEC 18 - 24 2025  
 
THE 0Z ECMWF, GEFS, AND CANADIAN ENSEMBLE MEAN SOLUTIONS FOR THE 8–14 DAY PERIOD  
PREDICT A FAIRLY CONSISTENT 500-HPA CIRCULATION PATTERN RELATIVE TO THE 6–10 DAY  
PERIOD ACROSS NORTH AMERICA AND THE SURROUNDING REGIONS. A VERY AMPLIFIED RIDGE  
AND POSITIVE 500-HPA HEIGHT ANOMALY PERSISTS TO THE WEST OF MAINLAND ALASKA. A  
TROUGH AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED  
DOWNSTREAM OVER EASTERN AND CENTRAL MAINLAND ALASKA AND SOUTHEAST ALASKA.  
POSITIVE 500-HPA HEIGHT ANOMALIES EXPAND ACROSS THE ENTIRE CONUS IN THE MANUAL  
BLEND AND THE 0Z ECMWF, GEFS, AND CANADIAN ENSEMBLE MEANS. NEAR TO BELOW NORMAL  
500-HPA HEIGHTS ARE PREDICTED ACROSS HAWAII DURING THE WEEK-2 PERIOD.  
 
ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR THE WESTERN ALEUTIAN  
ISLANDS IN THE 8–14 DAY PERIOD UNDER STRONG POSITIVE 500-HPA HEIGHT ANOMALIES.  
BELOW NORMAL TEMPERATURES ARE LIKELY ACROSS THE ALASKA MAINLAND IN THE WEEK-2  
PERIOD UNDER ANOMALOUS NORTHERLY MID-LEVEL FLOW. MODEL TOOLS FOR THE CONUS  
PREDICT LIKELY NEAR TO ABOVE NORMAL TEMPERATURES ACROSS MOST OF THE CONUS IN  
THE 8–14 DAY PERIOD UNDER A PERSISTENT RIDGE AND POSITIVE 500-HPA HEIGHT  
ANOMALIES. BELOW NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE NORTHERN  
PLAINS, THE UPPER MISSISSIPPI VALLEY, AS WELL AS PORTIONS OF THE NORTHEAST  
UNDER PREDICTED ANOMALOUS NORTHERLY FLOW THROUGH MOST OF THE 8–14 DAY PERIOD.  
THE CONSOLIDATION CONTINUES TO SUPPORT HIGH PROBABILITIES FOR ABOVE NORMAL  
TEMPERATURES FOR HAWAII.  
 
BELOW NORMAL PRECIPITATION IS FAVORED FOR SOUTHERN AND CENTRAL MAINLAND ALASKA  
IN THE WEEK-2 PERIOD UNDER ANOMALOUS NORTHERLY FLOW AHEAD OF THE AMPLIFIED  
RIDGE. ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR A SMALL AREA OF THE  
NORTHEASTERN COAST OF MAINLAND ALASKA, CONSISTENT WITH ALL ENSEMBLE MODEL  
PRECIPITATION FORECASTS. AHEAD OF THE TROUGH OVER THE NORTH PACIFIC, ENHANCED  
PROBABILITIES FOR ABOVE NORMAL PRECIPITATION CONTINUE TO BE LIKELY FOR MOST OF  
THE WESTERN CONUS, EXTENDING EASTWARD ACROSS THE NORTHERN PLAINS, THE UPPER  
MISSISSIPPI VALLEY, INTO THE GREAT LAKES, AND THE NORTHEAST REGIONS, CONSISTENT  
WITH THE PRECIPITATION CONSOLIDATION. BELOW NORMAL PRECIPITATION IS FAVORED FOR  
MOST OF THE SOUTHERN CONUS UNDER THE PREDICTED RIDGE. ABOVE NORMAL  
PRECIPITATION CONTINUES TO BE FAVORED FOR THE SOUTHERN FLORIDA PENINSULA,  
CONSISTENT WITH MOST TOOLS. THE PRECIPITATION CONSOLIDATION SUPPORTS SLIGHTLY  
ENHANCED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE NORTHWESTERN  
HAWAIIAN ISLANDS, WHILE BELOW NORMAL PRECIPITATION IS FAVORED FOR THE BIG  
ISLAND.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 11, AND 30% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON  
DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO  
OVERALL AGREEMENT ON THE EVOLVING MID-LEVEL CIRCULATION PATTERN, WITH  
DIFFERENCES IN TEMPERATURE AND PRECIPITATION FORECAST TOOLS FOR SOME AREAS.  
 
FORECASTER: LUKE H  
 
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 (GRAY, "N") NORMAL.  
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 (GRAY, "N")  
NORMAL. 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  
DECEMBER 18.  
 
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:  
20131213 - 19951129 - 19891122 - 20081208 - 19911204  
 
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:  
20131213 - 19951129 - 20081207 - 19911204 - 19891121  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR DEC 16 - 20 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A B IDAHO A A NEVADA A A  
W MONTANA A A E MONTANA A A WYOMING A A  
UTAH A A ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA N A S DAKOTA A A  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A N S TEXAS A N W TEXAS A B  
MINNESOTA N A IOWA A N MISSOURI A B  
ARKANSAS A N LOUISIANA A N WISCONSIN N A  
ILLINOIS A N MISSISSIPPI A N MICHIGAN N A  
INDIANA A A OHIO A A KENTUCKY A N  
TENNESSEE A N ALABAMA A B NEW YORK N A  
VERMONT N A NEW HAMP N N MAINE B A  
MASS N N CONN N N RHODE IS N N  
PENN N N NEW JERSEY N N W VIRGINIA N N  
MARYLAND N N DELAWARE N B VIRGINIA N B  
N CAROLINA N B S CAROLINA A B GEORGIA A B  
FL PNHDL A N FL PENIN A N AK N SLOPE B A  
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B B  
AK S INT B B AK SO COAST B B AK PNHDL B B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR DEC 18 - 24 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A A IDAHO A A NEVADA A A  
W MONTANA A A E MONTANA N A WYOMING A A  
UTAH A A ARIZONA A B COLORADO A A  
NEW MEXICO A B N DAKOTA B A S DAKOTA N A  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA B A IOWA A N MISSOURI A N  
ARKANSAS A B LOUISIANA A B WISCONSIN N A  
ILLINOIS A A MISSISSIPPI A B MICHIGAN N A  
INDIANA A A OHIO A A KENTUCKY A N  
TENNESSEE A N ALABAMA A B NEW YORK A A  
VERMONT B A NEW HAMP N A MAINE B A  
MASS N N CONN N N RHODE IS N N  
PENN A A NEW JERSEY A N W VIRGINIA A N  
MARYLAND A B DELAWARE A B VIRGINIA A B  
N CAROLINA A B S CAROLINA A B GEORGIA A B  
FL PNHDL A B FL PENIN A N AK N SLOPE B N  
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B B  
AK S INT B B AK SO COAST B B AK PNHDL B 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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