164
FXUS06 KWBC 162002
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 16 2025
6-10 DAY OUTLOOK FOR DEC 22 - 26 2025
6 TO 10 DAY OUTLOOK - VALID: DECEMBER 22-26, 2025
A HIGHLY AMPLIFIED PATTERN IS FORECAST FOR THE 6-10 DAY PERIOD ACROSS NORTH
AMERICA AND ADJACENT AREAS. A STRONG MID-LEVEL HIGH IS FORECAST TO BE CENTERED
ACROSS THE ALEUTIAN ISLANDS AND NORTH PACIFIC. DOWNSTREAM, NEGATIVE 500-HPA
HEIGHT ANOMALIES AND AN ASSOCIATED MID-LEVEL TROUGH ARE FORECAST FROM SOUTHEAST
ALASKA THROUGH THE NORTHEASTERN PACIFIC, OFFSHORE MUCH OF THE WESTERN
CONTIGUOUS U.S. (CONUS). THIS IS FORECAST TO BRING CONTINUED CHANCES FOR
ONSHORE FLOW INTO THE WESTERN CONUS DURING THE PERIOD. AN EXPANSIVE AND STRONG
AREA OF POSITIVE 500-HPA HEIGHT ANOMALIES REMAINS FORECAST TO BE CENTERED OVER
THE CENTRAL CONUS. 500-HPA HEIGHT RISES CONTINUE TO BE FORECAST OVER THE
EASTERN CONUS DURING THE PERIOD. IN HAWAII, NEAR NORMAL MID-LEVEL HEIGHTS ARE
FAVORED.
ACROSS THE CONUS, POSITIVE 500-HPA HEIGHT ANOMALIES ALONGSIDE WARM PACIFIC
FLOW, LEADS TO ABOVE NORMAL TEMPERATURES BEING FORECAST ACROSS MOST OF THE
CONUS. PROBABILITIES FOR ABOVE NORMAL EXCEED 90% FOR PORTIONS OF THE FOUR
CORNERS AND SOUTHERN PLAINS. THE ONE EXCEPTION ACROSS THE CONUS IS IN THE
NORTHEAST WHERE SOME RESIDUAL TROUGHING LEADS TO LINGERING CHANCES FOR BELOW
NORMAL TEMPERATURES. WEAKER CHANCES ARE FAVORED ACROSS THE NORTHERN TIER
DISPLACED FROM THE STRONGEST 500-HPA HEIGHT ANOMALIES AND ALONG THE WEST COAST
WHERE CLOUDS AND PRECIPITATION MAY LIMIT DIURNAL HEATING. IN CONTRAST TO THE
CONUS, ALASKA IS FORECAST TO HAVE MOSTLY BELOW NORMAL TEMPERATURE CHANCES.
CHANCES FOR BELOW NORMAL EXCEED 90% FOR PORTIONS OF SOUTHEAST ALASKA. ABOVE
NORMAL TEMPERATURES ARE FAVORED FOR PORTIONS OF THE ALEUTIANS. IN HAWAII, ABOVE
NORMAL TEMPERATURES REMAIN FAVORED.
ABOVE NORMAL PRECIPITATION IS LIKELY FOR MUCH OF THE WEST COAST. THE AMPLIFIED
PATTERN IS PRIMED TO BRING ATMOSPHERIC RIVER ACTIVITY INTO THE WEST COAST
DURING THE PERIOD. THE HIGHEST CHANCES FOR ABOVE NORMAL EXCEED 80% FOR CENTRAL
CALIFORNIA. THIS MAY LEAD TO HAZARDOUS CONDITIONS DURING THE HOLIDAY TRAVEL
PERIOD ACROSS PARTS OF THE WEST COAST. BELOW NORMAL PRECIPITATION IS FAVORED
OVER THE CENTRAL AND EASTERN CONUS WITH MID-LEVEL RIDGING LIMITING
PRECIPITATION CHANCES ACROSS MUCH OF THE REGION. THE EXCEPTION IS NEAR TO ABOVE
NORMAL OVER THE NORTHERN TIER OF THE CONUS DISPLACED FROM THE STRONGEST
POSITIVE 500-HPA HEIGHT ANOMALIES. THIS REGION COULD SEE SHORTWAVE TROUGHS
MOVING THROUGH. IN ALASKA, NEAR NORMAL PRECIPITATION IS FAVORED FOR MOST OF
MAINLAND AND SOUTHEAST ALASKA. A SLIGHT TILT TOWARDS BELOW NORMAL PRECIPITATION
IS FAVORED FOR THE ALEUTIANS AND SOUTHERN MAINLAND ALASKA AND A SLIGHT TILT
TOWARDS ABOVE OVER THE NORTHWESTERN MAINLAND. ABOVE NORMAL IS FAVORED OVER MUCH
OF HAWAII, EXCEPT FOR PORTIONS OF THE BIG ISLAND IN AGREEMENT WITH REFORECAST
TOOLS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 25% 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
GENERALLY GOOD MODEL AGREEMENT WITH STRONG CONSISTENCY FROM YESTERDAY.
8-14 DAY OUTLOOK FOR DEC 24 - 30 2025
THE 500-HPA HEIGHT FORECAST REMAINS QUITE CONSISTENT RELATIVE TO THE 6-10 DAY
PERIOD AND YESTERDAY'S FORECAST. AN AMPLIFIED MID-LEVEL RIDGE REMAINS FAVORED
OVER THE NORTH PACIFIC AND ALEUTIAN ISLANDS. A MID-LEVEL TROUGH IS FORECAST TO
REMAIN JUST OFFSHORE THE WEST COAST. MEANWHILE, EXPANSIVE MID-LEVEL RIDGING
REMAINS FORECAST OVER THE CENTRAL AND EASTERN CONUS ALBEIT A LITTLE EAST
RELATIVE TO THE EARLIER PERIOD. THERE ARE SOME INDICATIONS THAT TROUGHING MAY
TRY TO REDEVELOP OVER THE NORTHEASTERN CONUS AS A NEGATIVE NORTH ATLANTIC
OSCILLATION (-NAO) PATTERN MAY DEVELOP. IN HAWAII, NEAR NORMAL 500-HPA HEIGHTS
REMAIN FORECAST.
AS WITH THE 500-HPA HEIGHT FORECAST, THE TEMPERATURE FORECAST FOR WEEK-2 IS
QUITE CONSISTENT WITH YESTERDAY AND THE 6-10 DAY PERIOD. ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR NEARLY ALL OF THE CONUS WITH THE STRONGEST CHANCES
EXCEEDING 90% OVER THE SOUTHERN PLAINS. NEAR TO WEAKLY ABOVE NORMAL IS FAVORED
FOR THE IMMEDIATE WEST COAST TIED TO ONSHORE FLOW BRINGING CLOUDS AND
PRECIPITATION TO THE WEST COAST. THERE ARE WEAKER CHANCES FOR ABOVE NORMAL
TEMPERATURES OVER THE NORTHERN TIER AS WELL DISPLACED FROM THE MID-LEVEL RIDGE
AND MORE PRONE TO SHORTWAVE TROUGHS MOVING INTO NORTH AMERICA. IN THE
NORTHEAST, THERE IS MORE UNCERTAINTY REGARDING THE 7 DAY MEAN TEMPERATURES AS A
-NAO GENERALLY BRINGS COOLER CONDITIONS TO THE EAST HOWEVER TOOLS HAVE TRENDED
SLIGHTLY WARMER TODAY RELATIVE TO YESTERDAY. THEREFORE, A TRANSITION FROM
WEAKLY ABOVE NORMAL TO WEAKLY BELOW NORMAL IS FORECAST FROM THE MID-ATLANTIC
AND GREAT LAKES TO NEW ENGLAND. BELOW NORMAL TEMPERATURES REMAIN LIKELY ACROSS
MOST OF ALASKA DURING WEEK-2 AS THE STAYING POWER OF THIS PATTERN APPEARS
ROBUST. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR HAWAII.
ABOVE NORMAL PRECIPITATION REMAINS LIKELY FOR THE WEST COAST WITH CONTINUED
CHANCES FOR ATMOSPHERIC RIVER ACTIVITY TO IMPACT THE REGION THROUGHOUT WEEK-2.
TOOLS CONTINUE TO COME INTO BETTER AGREEMENT FOR THE TROUGH ALONG THE WEST
COAST TO RELOAD BY THE SECOND HALF OF THE PERIOD INCREASING CHANCES FOR ABOVE
NORMAL PRECIPITATION IN THE PACIFIC NORTHWEST IN THE SECOND HALF OF WEEK-2
AFTER A DRIER START TO THE PERIOD. BENEATH THE 500-HPA HEIGHT RIDGE OVER THE
CENTRAL AND EASTERN CONUS, BELOW NORMAL PRECIPITATION IS GENERALLY FAVORED WITH
THE STRONGEST CHANCES ACROSS THE SOUTHEAST. NEAR TO SLIGHTLY ABOVE IS FAVORED
FOR THE NORTHEAST AND GREAT LAKES DISPLACED FROM THE STRONGEST POSITIVE 500-HPA
HEIGHT ANOMALIES. NEAR NORMAL IS FAVORED OVER MUCH OF MAINLAND ALASKA EXCLUDING
PORTIONS OF THE SOUTHERN COAST WHERE BELOW NORMAL IS FAVORED. IN HAWAII, ABOVE
NORMAL IS FORECAST CONSISTENT WITH THE DYNAMICAL GUIDANCE.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 25% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOVE-AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT ON THE CONTINUED PERSISTENCE OF THE HEIGHT, TEMPERATURE,
AND PRECIPITATION PATTERNS.
FORECASTER: RYAN BOLT
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:
20101210 - 19951130 - 20121126 - 20121201 - 20211203
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:
20101211 - 19951125 - 19951130 - 20121126 - 20131214
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 22 - 26 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 A A WYOMING A A
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A B N DAKOTA A A S DAKOTA A B
NEBRASKA A B KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A A IOWA A B MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN A N
ILLINOIS A B MISSISSIPPI A B MICHIGAN A N
INDIANA A N OHIO A N KENTUCKY A B
TENNESSEE A B ALABAMA A B NEW YORK N N
VERMONT B N NEW HAMP B N MAINE B N
MASS B N CONN N N RHODE IS B N
PENN A N NEW JERSEY A B 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 B AK N SLOPE B A
AK ALEUTIAN B B AK WESTERN B N AK INT BSN B N
AK S INT B N AK SO COAST B B AK PNHDL B N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 24 - 30 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 A A WYOMING A A
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A N N DAKOTA A N S DAKOTA A B
NEBRASKA A B KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A N W TEXAS A B
MINNESOTA A N IOWA A N MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN A N
ILLINOIS A N MISSISSIPPI A B MICHIGAN A A
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE A B ALABAMA A B NEW YORK N N
VERMONT N N NEW HAMP N N MAINE B N
MASS N N CONN N N RHODE IS N B
PENN A N NEW JERSEY N B 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 B AK N SLOPE B N
AK ALEUTIAN B B AK WESTERN B N AK INT BSN B N
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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