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FXUS06 KWBC 302043
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE DECEMBER 30 2025
6-10 DAY OUTLOOK FOR JAN 05 - 09 2026
THE 0Z ECMWF, GEFS, AND CANADIAN ENSEMBLE MEAN FORECASTS AGREE ON THE
LARGE-SCALE CIRCULATION PATTERN OVER NORTH AMERICA AT THE START OF THE 6-10 DAY
PERIOD. HOWEVER MODEL SOLUTIONS QUICKLY DIVERGE, AND 6-10 DAY MEAN SOLUTIONS
SHOW SIGNIFICANT DIFFERENCES AND UNCERTAINTY. THE MANUAL BLEND OF 500-HPA
HEIGHT FORECASTS USES A NEARLY EQUAL AVERAGE OF THESE THREE 0Z ENSEMBLE MEANS.
THE MANUAL BLEND INDICATES A LARGE POSITIVE 500-HPA HEIGHT ANOMALY OVER THE
NORTH PACIFIC AND A NEGATIVE 500-HPA HEIGHT ANOMALY OVER MAINLAND ALASKA,
EXTENDING SOUTHEASTWARD OVER THE PACIFIC COAST OF CANADA AND SOUTHEAST ALASKA.
A TROUGH AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES NEAR THE WEST COAST
OF THE CONTIGUOUS U.S. (CONUS) HAVE WEAKENED SLIGHTLY FROM YESTERDAY'S 6-10 DAY
MANUAL BLEND FORECAST. WEAK POSITIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED
OVER THE CENTRAL CONUS IN THE MANUAL BLEND AND INDIVIDUAL ENSEMBLE MEANS, WHILE
A WEAK TROUGH AND NEGATIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED OVER THE
EASTERN CONUS.
BELOW NORMAL TEMPERATURES ARE FAVORED OVER MOST OF MAINLAND ALASKA WITH GREATER
PROBABILITIES OVER THE NORTHWEST, UNDER NEGATIVE 500-HPA HEIGHT ANOMALIES. WITH
INCREASING ONSHORE FLOW, NEAR-NORMAL TEMPERATURES ARE MOST LIKELY FOR
SOUTHEASTERN MAINLAND ALASKA AND THE ALASKA PANHANDLE. ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR THE ALEUTIANS UNDER POSITIVE 500-HPA HEIGHT
ANOMALIES. WEAK 500-HPA HEIGHT ANOMALIES AND RIDGING OVER THE SOUTH-CENTRAL
CONUS FAVOR ABOVE NORMAL TEMPERATURES ACROSS MOST OF THE CONUS, EXCLUDING THE
NORTHEASTERN CONUS. NEAR-TO-BELOW NORMAL TEMPERATURES ARE FAVORED OVER THE
NORTHEAST, UNDER A PREDICTED TROUGH. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR
MOST OF HAWAII, EXCLUDING SOUTHEASTERN AREAS OF THE BIG ISLAND, CONSISTENT WITH
MODEL BASED TOOLS.
INCREASING WESTERLY FLOW INTO ALASKA FAVORS ABOVE NORMAL PRECIPITATION ACROSS
MOST OF THE STATE EXCLUDING THE NORTH SLOPE, WHERE RELATIVELY LITTLE
PRECIPITATION IS FORECAST. AHEAD OF A PREDICTED TROUGH, ABOVE NORMAL
PRECIPITATION IS FAVORED FROM THE PACIFIC COAST OF THE CONUS TO THE ROCKIES,
WITH PROBABILITIES EXCEEDING 60 PERCENT IN CLIMATOLOGICALLY DRIER REGIONS OF
SOUTHERN CALIFORNIA. MODEL FORECASTS HAVE SHIFTED TO SLIGHTLY FAVORING ABOVE
NORMAL PRECIPITATION FOR PARTS OF THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY. ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS HAWAII, SUPPORTED BY THE
PRECIPITATION CONSOLIDATION OF CALIBRATED GEFS AND ECMWF FORECASTS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 34% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 33% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
OVERALL AGREEMENT AMONG ENSEMBLE MEANS ON THE AVERAGE 500-HPA HEIGHT PATTERN,
OFFSET BY DIVERGENCE IN THE MODEL SOLUTIONS AS THE PERIOD PROGRESSES AND SOME
DIFFERENCES AMONG TEMPERATURE AND PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR JAN 07 - 13 2026
A TRANSITION IN THE MID-LEVEL CIRCULATION PATTERN OVER AND NEAR ALASKA DURING
THE WEEK-2 PERIOD LEADS TO LARGE UNCERTAINTIES IN THE MEAN 8-14 DAY 500-HPA
HEIGHT FORECAST OVER THE CONUS, DIFFERENCES IN LARGE-SCALE FEATURES BETWEEN
ENSEMBLE MEANS, AND NEAR ZERO HEIGHT ANOMALIES OVER THE CONUS IN THE MANUAL
BLEND OF MODELS. A RIDGE AND ASSOCIATED POSITIVE 500-HPA HEIGHT ANOMALY IS
PREDICTED OVER THE GULF OF ALASKA AND MAINLAND ALASKA IN THE 8-14 DAY PERIOD
MANUAL BLEND. THE GEFS AND ECMWF ENSEMBLE MEANS PREDICT PERSISTENCE OF A TROUGH
AND NEGATIVE 500-HPA HEIGHT ANOMALIES OVER THE WEST COAST OF THE CONUS INTO THE
START OF THE 8-14 DAY PERIOD, BEFORE DIVERGING. NEGATIVE 500-HPA HEIGHT
ANOMALIES AND TROUGHING OVER THE EAST AT THE START OF THE PERIOD GIVE WAY TO
POSITIVE 500-HPA HEIGHT ANOMALIES TOWARDS THE MIDDLE OF THE PERIOD IN ALL
ENSEMBLE MEAN MODEL SOLUTIONS.
NEAR-TO-BELOW NORMAL TEMPERATURES ARE FAVORED FOR WESTERN MAINLAND ALASKA IN
THE 8-14 DAY PERIOD, PRIMARILY SUPPORTED BY CALIBRATED ECMWF TEMPERATURE
FORECASTS THAT PREDICT SIGNIFICANT BELOW NORMAL TEMPERATURES AT THE START OF
THE PERIOD. ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR THE ALEUTIANS
UNDER PREDOMINANTLY POSITIVE 500-HPA HEIGHT ANOMALIES. ABOVE NORMAL
TEMPERATURES ARE INCREASINGLY FAVORED FOR MOST OF EASTERN MAINLAND ALASKA AND
NORTHERN AREAS OF SOUTHEAST ALASKA, UNDER THE EMERGING POSITIVE 500-HPA HEIGHT
ANOMALIES. ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED ACROSS MOST OF THE
CONUS IN THE 8-14 DAY PERIOD, RELATED TO PREDICTED RIDGING AND POSITIVE 500-HPA
HEIGHT ANOMALIES THAT PROGRESS ACROSS THE CONUS DURING THE PERIOD. NEAR NORMAL
TEMPERATURES ARE FAVORED FOR PARTS OF THE PACIFIC NORTHWEST AND MOST OF THE
NORTHEAST DURING THE 8-14 DAY PERIOD, WHERE MID-LEVEL HEIGHT ANOMALIES ARE
CHANGING THROUGH THE PERIOD AND UNCERTAINTY IS GREATER. ABOVE NORMAL
TEMPERATURES ARE FAVORED ACROSS HAWAII IN THE 8-14 DAY PERIOD, CONSISTENT WITH
THE TEMPERATURE CONSOLIDATION.
ABOVE NORMAL PRECIPITATION CONTINUES TO BE FAVORED FOR THE ALEUTIANS AND MOST
OF WESTERN AND SOUTHERN MAINLAND ALASKA, AHEAD OF A LOW PRESSURE SYSTEM AT THE
START OF THE PERIOD IN DYNAMICAL MODEL FORECASTS. ABOVE NORMAL PRECIPITATION IS
SLIGHTLY FAVORED ACROSS ALMOST THE ENTIRE CONUS IN THE 8-14 DAY PERIOD,
CONSISTENT WITH MOST DYNAMICAL MODEL FORECASTS AND THE CONSOLIDATION.
PROBABILITIES EXCEED 50 PERCENT FOR PARTS OF THE CLIMATOLOGICALLY DRIER
SOUTHWEST, AND EXCEED 40 PERCENT FROM THE SOUTHWESTERN CONUS TO THE CENTRAL
APPALACHIANS, CONSISTENT WITH THE CONSOLIDATION. ABOVE NORMAL PRECIPITATION IS
LIKELY FOR HAWAII, CONSISTENT WITH THE CONSOLIDATION.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 35% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 32% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
INCREASING DIFFERENCES IN DYNAMICAL MODEL MID-LEVEL HEIGHT FORECASTS AS THE
PERIOD PROGRESSES, AS WELL AS DIFFERENCES AMONG THE MODEL TEMPERATURE AND
PRECIPITATION TOOLS.
FORECASTER: D COLLINS
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
JANUARY 15.
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:
20221210 - 20211226 - 20211217 - 20041229 - 20081229
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:
20041228 - 20211222 - 20211217 - 20050108 - 19901215
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 05 - 09 2026
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 A A WYOMING A A
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A N S DAKOTA A N
NEBRASKA A N KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A N W TEXAS A A
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS A A LOUISIANA A N WISCONSIN A N
ILLINOIS A N MISSISSIPPI A N MICHIGAN N N
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE A N ALABAMA A N NEW YORK N N
VERMONT B N NEW HAMP B N MAINE B A
MASS B A CONN B A RHODE IS B A
PENN N N NEW JERSEY N N W VIRGINIA A N
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A N AK N SLOPE B N
AK ALEUTIAN A A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST N A AK PNHDL N A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 07 - 13 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N N OREGON A A NRN CALIF A A
SRN CALIF A A IDAHO A A NEVADA A 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 A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA A A IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A A
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT N A NEW HAMP N A MAINE N A
MASS N A CONN N A RHODE IS N A
PENN N A NEW JERSEY N A W VIRGINIA A A
MARYLAND A A DELAWARE N A VIRGINIA A A
N CAROLINA A A S CAROLINA A A GEORGIA A A
FL PNHDL A N FL PENIN A N AK N SLOPE N N
AK ALEUTIAN A A AK WESTERN N A AK INT BSN A A
AK S INT A A AK SO COAST A A AK PNHDL N N
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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