051
FXUS06 KWBC 182002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST THU DECEMBER 18 2025
6-10 DAY OUTLOOK FOR DEC 24 - 28 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. IN THE NORTHWESTERN ATLANTIC, BELOW NORMAL 500-HPA HEIGHTS
ARE FORECAST ALONG WITH WEAK TROUGHING. 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, SOUTHERN PLAINS, AND LOWER MISSISSIPPI VALLEY. IN THE NORTHEAST, THE
INFLUENCE OF MID-LEVEL TROUGHING OVER THE NORTHWESTERN ATLANTIC FAVORS SLIGHT
CHANCES FOR NEAR TO BELOW NORMAL TEMPERATURES. WEAKER CHANCES FOR ABOVE NORMAL
TEMPERATURES ARE FAVORED ACROSS THE NORTHERN TIER DISPLACED FROM THE STRONGEST
500-HPA HEIGHT ANOMALIES. ALONG THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA
COAST CLOUDS AND PRECIPITATION MAY LIMIT DIURNAL HEATING FAVORING NEAR TO BELOW
NORMAL TEMPERATURES IN THIS REGION. IN CONTRAST TO THE CONUS, ALASKA IS
FORECAST TO HAVE MOSTLY BELOW NORMAL TEMPERATURE CHANCES. CHANCES FOR BELOW
NORMAL EXCEED 80% FOR SOUTHEAST ALASKA AND INTO THE SOUTHEASTERN MAINLAND.
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 70% FOR CENTRAL
AND SOUTHERN CALIFORNIA INTO PORTIONS OF NEVADA, UTAH, AND ARIZONA. 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
SOUTHEASTERN CONUS WITH MID-LEVEL RIDGING LIMITING PRECIPITATION CHANCES ACROSS
MUCH OF THE REGION. NEAR TO ABOVE NORMAL PRECIPITATION IS FAVORED 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. NEAR TO ABOVE NORMAL IS FAVORED FOR HAWAII, WITH
ABOVE NORMAL FAVORED OVER KAUAI AND OAHU.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 35% 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
GENERALLY GOOD MODEL AGREEMENT WITH STRONG CONSISTENCY FROM YESTERDAY.
8-14 DAY OUTLOOK FOR DEC 26, 2025 - JAN 01, 2026
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 LIKELY
OVER THE NORTH PACIFIC AND ALEUTIAN ISLANDS. MID-LEVEL TROUGHING IS FORECAST TO
REMAIN ALONG AND NEAR SOUTHEAST ALASKA AND THE PACIFIC NORTHWEST. THIS TROUGH
DOES NOT DIG AS FAR SOUTH IN THE WEEK-2 MEAN RELATIVE TO PRIOR FORECASTS WITH
THE STRONGEST ANOMALIES CENTERED OVER SOUTHEAST ALASKA. 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 DEVELOP 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 80% OVER THE SOUTHERN PLAINS. NEAR NORMAL IS FAVORED FOR MUCH OF 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 ACROSS 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. 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 FOR
THE SOUTHEAST, SOUTHERN MID-ATLANTIC, LOWER MISSISSIPPI VALLEY, AND PORTIONS OF
THE PLAINS. OTHERWISE, NEAR NORMAL IS FAVORED FOR MOST AREAS EAST OF THE
ROCKIES AS ENERGY FROM THE PACIFIC MAY PROMOTE SHORTWAVE TROUGHS TO MOVE
THROUGH THE EASTERN CONUS. NEAR NORMAL IS FAVORED OVER MUCH OF MAINLAND ALASKA
EXCLUDING PORTIONS OF THE SOUTHERN COAST WHERE BELOW NORMAL IS FAVORED. IN
HAWAII, ABOVE NORMAL PRECIPITATION IS AGAIN FORECAST. DYNAMICAL GUIDANCE HAS
BEEN CONSISTENT WITH HIGH CHANCES FOR ABOVE NORMAL PRECIPITATION BETWEEN THE
MAIN ISLANDS AND MIDWAY. THE STRONGEST PROBABILITIES FOR ABOVE NORMAL HAVE
SHIFTED SLIGHTLY EASTWARD RELATIVE TO YESTERDAY AND 50-60% CHANCES FOR ABOVE
NORMAL ARE FAVORED FOR KAUAI AND OAHU.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 35% 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: 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
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:
20101211 - 19951201 - 20121201 - 20211203 - 19980101
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 - 19951130 - 20121127 - 20121202 - 20131214
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 24 - 28 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N 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 B KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A N W TEXAS A N
MINNESOTA A N IOWA A B MISSOURI A N
ARKANSAS A B LOUISIANA A B WISCONSIN A A
ILLINOIS A N MISSISSIPPI A B MICHIGAN A A
INDIANA A N OHIO A A KENTUCKY A N
TENNESSEE A B ALABAMA A B NEW YORK N A
VERMONT N A NEW HAMP N N MAINE B N
MASS N N CONN N N RHODE IS N N
PENN A A NEW JERSEY A N W VIRGINIA A N
MARYLAND A N 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 N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 26, 2025 - JAN 01, 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON A A NRN CALIF N 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 N OKLAHOMA A N
N TEXAS A N S TEXAS A N W TEXAS A N
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS A N LOUISIANA A B WISCONSIN A N
ILLINOIS A N MISSISSIPPI A B MICHIGAN A N
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE A N ALABAMA A B NEW YORK N N
VERMONT N N NEW HAMP B N MAINE B N
MASS B B CONN N B RHODE IS B B
PENN N N NEW JERSEY N B W VIRGINIA A N
MARYLAND N B DELAWARE N B VIRGINIA N B
N CAROLINA N 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 B AK INT BSN B N
AK S INT B B AK SO COAST B B AK PNHDL B 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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