055
FXUS06 KWBC 142002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST SUN DECEMBER 14 2025
6-10 DAY OUTLOOK FOR DEC 20 - 24 2025
DYNAMICAL MODELS ARE IN GOOD AGREEMENT REGARDING A SIGNIFICANT PATTERN CHANGE
ACROSS MUCH OF THE EASTERN HALF OF THE U.S. DURING THE WEEK OF CHRISTMAS.
MID-LEVEL RIDGING IS FORECAST TO AMPLIFY OVER THE CONTIGUOUS U.S. (CONUS) EAST
OF THE ROCKIES WITH TROUGHING OVER CANADA AND EXTENDING ALONG THE WEST COAST OF
THE CONUS. TODAY'S 500-HPA MANUAL HEIGHT BLEND FOR THE 6-10 DAY PERIOD DEPICTS
ABOVE-NORMAL HEIGHTS ACROSS MUCH OF THE CONUS, WITH THE EXCEPTIONS BEING OVER
THE PACIFIC NORTHWEST, NORTHERN CALIFORNIA, NORTHERN GREAT BASIN, AND EXTENDING
ACROSS THE NORTH-CENTRAL CONUS CLOSE TO THE CANADIAN BORDER, WHERE BELOW-NORMAL
HEIGHTS ARE INDICATED. A PERSISTENT PATTERN IS FAVORED ACROSS ALASKA WITH A
+360 METER POSITIVE HEIGHT ANOMALY CENTER DEPICTED TO THE SOUTH OF THE
ALEUTIANS IN THE MANUAL BLEND, AND ABOVE-NORMAL HEIGHTS EXTENDING OVER MUCH OF
THE MAINLAND. BELOW-NORMAL HEIGHTS REMAIN FORECAST FOR SOUTHEAST ALASKA CLOSER
TO THE TROUGHING OVER CANADA. NEAR-NORMAL 500-HPA HEIGHTS ARE FORECAST ACROSS
HAWAII AS TROUGHING OVER THE CENTRAL PACIFIC IS PREDICTED TO WEAKEN.
WIDESPREAD ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE FAVORED THROUGHOUT MOST
OF THE CONUS DURING THE PERIOD, EVEN REACHING INTO MUCH OF THE MIDWEST, GREAT
LAKES, AND MID-ATLANTIC TIED TO EXPANDING RIDGING. MANY OF THESE AREAS ARE
FAVORED TO HAVE A WARM HOLIDAY WEEK BY CLIMATOLOGICAL STANDARDS, AND A WELCOME
REPRIEVE FROM SOME OF THE COLDER WEATHER EXPERIENCED EARLIER IN DECEMBER.
ELONGATED TROUGHING ACROSS CANADA CONTINUES TO FAVOR AN ACTIVE NORTHERN STREAM
AND INTRUSIONS OF COLD AIR ACROSS NORTHERN AREAS OF THE CONUS. THEREFORE,
CHANCES OF NEAR-TO BELOW NORMAL TEMPERATURES REMAIN ELEVATED ACROSS THE
NORTH-CENTRAL CONUS AND MUCH OF THE NORTHEAST, AS WELL AS COASTAL AREAS OF THE
NORTHWEST TIED TO AMPLIFYING TROUGHING OFF THE PACIFIC COAST. DEEP RIDGING
ACROSS THE ALEUTIANS AND ASSOCIATED NORTHERLY MID-LEVEL FLOW OVER ALASKA FAVORS
HIGH PROBABILITIES OF BELOW-NORMAL TEMPERATURES ACROSS MUCH OF MAINLAND AND
SOUTHEAST ALASKA. THIS IS SUPPORTED BY UNCALIBRATED AND REFORECAST TOOLS, IN
ADDITION TO TELECONNECTION ANALYSIS WITH THE POSITIVE HEIGHT ANOMALY CENTER
SOUTH OF THE ALEUTIANS. CONVERSELY, ODDS FOR ABOVE-NORMAL TEMPERATURES ARE
INCREASED OVER THE ALEUTIANS AND THE FAR WESTERN MAINLAND. HIGH PROBABILITIES
OF ABOVE-NORMAL TEMPERATURES ARE FORECAST FOR HAWAII, CONSISTENT WITH THE
CONSOLIDATION REFORECAST TOOL.
ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE INCREASED OVER THE WESTERN AND
NORTH-CENTRAL CONUS TIED TO CONTINUED ATMOSPHERIC RIVER ACTIVITY. THE HIGHEST
PROBABILITIES (GREATER THAN 80 PERCENT) ARE FAVORED ACROSS NORTHERN CALIFORNIA
AND NORTHWESTERN NEVADA. HOWEVER, ELEVATED PROBABILITIES FOR ABOVE-NORMAL
PRECIPITATION ALSO EXTEND INTO SOUTHERN CALIFORNIA AND ARIZONA, CONSISTENT WITH
A SOUTHWARD SHIFT IN THE STRONGEST MOISTURE ADVECTION. RIDGING DOWNSTREAM
FAVORS ELEVATED PROBABILITIES FOR BELOW-NORMAL PRECIPITATION ACROSS PARTS OF
THE CENTRAL AND SOUTHERN PLAINS, GULF COAST, SOUTHEAST, AND MID-ATLANTIC.
CONTINUED IMPULSES OF NORTHERN STREAM ENERGY FAVOR NEAR-NORMAL PRECIPITATION
ACROSS PORTIONS OF THE OHIO VALLEY AND NORTHEAST. OVER ALASKA, OFFSHORE FLOW
SUPPORTS ELEVATED CHANCES OF BELOW-NORMAL PRECIPITATION ACROSS SOUTHERN AND
SOUTHEASTERN PARTS OF THE STATE, WHILE A MORE NORTHWARD ORIENTED STORM TRACK
FAVORS ELEVATED CHANCES FOR ABOVE-NORMAL PRECIPITATION OVER THE NORTHERN
TWO-THIRDS OF THE MAINLAND. PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION ARE
INCREASED ACROSS NORTHWESTERN HAWAII, AND DECREASE SOUTHEASTWARD AS TROUGHING
OVER THE CENTRAL PACIFIC WEAKENS, WITH BELOW-NORMAL PRECIPITATION FAVORED FOR
SOUTHEASTERN AREAS OF THE BIG ISLAND.
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 MODEL AGREEMENT REGARDING THE MID-LEVEL PATTERN, OFFSET BY SOME
UNCERTAINTY REGARDING NORTHERN STREAM ENERGY AND A POTENTIAL EXTENSION OF
ATMOSPHERIC RIVER ACTIVITY INTO SOUTHERN CALIFORNIA.
8-14 DAY OUTLOOK FOR DEC 22 - 28 2025
THE 500-HPA HEIGHT PATTERN DISCUSSED IN THE 6-10 OUTLOOK IS LIKELY TO PERSIST
INTO WEEK-2. THE 0Z ECMWF AND CANADIAN ENSEMBLES SIGNIFICANTLY AMPLIFY
TROUGHING OFF THE WEST COAST OF THE CONUS WHILE THE GEFS IS A BIT LESS ROBUST.
HOWEVER, THE PATTERN PROGRESSION REMAINS CONSISTENT WITH ENHANCED ATMOSPHERIC
RIVER ACTIVITY EXTENDING FURTHER SOUTH INTO CALIFORNIA AND THE SOUTHWEST DURING
THE FIRST HALF OF THE PERIOD BEFORE POTENTIALLY RETREATING BACK NORTH TO THE
PACIFIC NORTHWEST. FURTHER DOWNSTREAM, THE MID-LEVEL HEIGHT PATTERN DURING
WEEK-2 RESEMBLES A POSITIVE PHASE OF THE ARCTIC OSCILLATION (+AO), WITH
ABOVE-NORMAL HEIGHTS OVER THE LOWER LATITUDES OF THE CONUS, AND BELOW-NORMAL
HEIGHTS ACROSS CANADA AND THE ARCTIC. THE WEEK-2 MANUAL HEIGHT BLEND SUPPORTS
THIS, WITH BROADLY POSITIVE HEIGHT ANOMALIES EAST OF THE ROCKIES, PEAKING AT
+150 METERS OVER THE MIDDLE MISSISSIPPI VALLEY. BELOW-NORMAL HEIGHTS ARE
DEPICTED ACROSS PARTS OF THE WESTERN CONUS, NORTHERN NEW ENGLAND, AND EASTERN
ALASKA, WITH ABOVE-NORMAL HEIGHTS INDICATED OVER WESTERN ALASKA TIED TO A
PERSISTENT RIDGE AXIS CENTERED OVER THE ALEUTIANS. NEAR-NORMAL HEIGHTS ARE
FORECAST ACROSS HAWAII, ALTHOUGH RISING MID-LEVEL HEIGHTS ARE POSSIBLE ACROSS
THE NORTHERN ISLANDS LATER IN THE PERIOD AS POSITIVE HEIGHT ANOMALIES
ORIGINATING OVER ALASKA EXPAND FURTHER SOUTHWARD OVER THE PACIFIC.
DOMINANT MID-LEVEL RIDGING CONTINUES TO FAVOR UNSEASONABLY WARM TEMPERATURES
ACROSS MUCH OF THE CONUS DURING WEEK-2, WITH THE HIGHEST PROBABILITIES (GREATER
THAN 90 PERCENT) OVER THE SOUTHERN HIGH PLAINS AND ADJACENT AREAS OF THE
SOUTHWEST. THE STRONGEST SIGNALS FOR BELOW-NORMAL TEMPERATURES REMAIN ACROSS
THE PACIFIC NORTHWEST AND THE NORTHERN TIER INCLUDING NEW ENGLAND WHERE A MORE
CYCLONIC FLOW PATTERN IS PREDICTED WITH GREATER INFLUENCE FROM TROUGHING.
ANOMALOUSLY COLD WEATHER IS FAVORED TO PERSIST ACROSS MOST OF ALASKA TIED TO
THE RIDGING UPSTREAM OVER THE ALEUTIANS. THE HIGHEST CHANCES FOR BELOW-NORMAL
TEMPERATURES ARE FORECAST ACROSS THE SOUTHEASTERN PORTION OF THE STATE,
CONSISTENT WITH THE ECMWF AND GEFS REFORECAST TOOLS. SOME AREAS ARE LIKELY TO
EXPERIENCE TEMPERATURES AT LEAST 10 TO UPWARDS OF 20 DEG F BELOW-AVERAGE BASED
ON UNCALIBRATED GUIDANCE, ALONG WITH DANGEROUSLY COLD WIND CHILLS. CONVERSELY,
HIGH PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES REMAIN FAVORED ACROSS HAWAII
BASED ON THE CONSOLIDATED REFORECAST TOOL.
ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE INCREASED FROM THE WEST COAST OF
THE CONUS EASTWARD TO THE ROCKIES ASSOCIATED WITH CONTINUED ATMOSPHERIC RIVER
ACTIVITY. EARLY IN THE PERIOD, THE STRONGEST MOISTURE ADVECTION IS FAVORED
ACROSS CALIFORNIA AND THE SOUTHWEST, WITH A NORTHWARD RETREAT BACK INTO THE
PACIFIC NORTHWEST MORE LIKELY LATER IN WEEK-2. THE 0Z ECMWF, GEFS, AND CANADIAN
ENSEMBLES CONTINUE TO INDICATE SEVERAL INCHES OF RAIN (HIGH ELEVATION SNOW)
ALONG PORTIONS OF THE WEST COAST DURING THE PERIOD RESULTING IN SIGNIFICANT
FLOODING CONCERNS OVER SOME AREAS GIVEN THE PERSISTENT PATTERN. RIDGING FAVORS
A MUCH DRIER PATTERN ACROSS THE CENTRAL AND SOUTHEASTERN CONUS, WITH
BELOW-NORMAL PRECIPITATION CHANCES INCREASED OVER THESE AREAS. AN ACTIVE
NORTHERN STREAM SUPPORTS SLIGHTLY ELEVATED CHANCES FOR ABOVE-NORMAL
PRECIPITATION OVER THE NORTHERN PLAINS, THROUGH PARTS OF THE MIDWEST, OHIO
VALLEY, GREAT LAKES, AND NORTHEAST. REFORECAST TOOLS ARE IN GOOD AGREEMENT
SUPPORTING CONTINUED ENHANCED BELOW-NORMAL PRECIPITATION CHANCES OVER SOUTHERN
ALASKA, WITH ABOVE-NORMAL PRECIPITATION MORE LIKELY OVER THE CENTRAL AND
NORTHERN MAINLAND. ODDS FOR ABOVE-NORMAL PRECIPITATION ARE SLIGHTLY INCREASED
ACROSS NORTHWESTERN HAWAII, WITH NEAR-NORMAL PRECIPITATION FAVORED FARTHER
SOUTHEAST OVER THE ISLAND CHAIN.
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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT REGARDING THE PLACEMENT OF AMPLIFIED FEATURES.
FORECASTER: THOMAS COLLOW
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:
19951129 - 20101210 - 19951124 - 20121125 - 20171228
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:
19951126 - 20131214 - 19951201 - 20101211 - 20121126
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 20 - 24 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B 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 B
NEW MEXICO A B N DAKOTA B A S DAKOTA A N
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 B MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN N 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 B N NEW HAMP B N MAINE B N
MASS N N CONN N N RHODE IS N 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 N A
AK ALEUTIAN A B AK WESTERN B A AK INT BSN B A
AK S INT B B AK SO COAST B B AK PNHDL B B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 22 - 28 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B 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 N A S DAKOTA A N
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 N MISSOURI A B
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 B A
VERMONT B N NEW HAMP B N MAINE B N
MASS B N CONN B N RHODE IS B N
PENN A N 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 A
AK ALEUTIAN A B AK WESTERN B A AK INT BSN B A
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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