862
FXUS06 KWBC 241918
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MARCH 24 2025
6-10 DAY OUTLOOK FOR MAR 30 - APR 03, 2025
THE GEFS, ECENS AND CANADIAN ENSEMBLE MEAN 500-HPA HEIGHT FORECASTS ARE IN VERY
GOOD AGREEMENT TODAY OVER THE FORECAST DOMAIN. THESE MODELS PREDICT A MID-LEVEL
TROUGH AND WELL BELOW NORMAL 500-HPA HEIGHTS OVER THE GULF OF ALASKA AND
EASTERN PACIFIC, WITH A NEGATIVE HEIGHT ANOMALY CENTER (-180 TO -210 METERS ON
THE MANUAL HEIGHT BLEND) CENTERED NEAR 43N/140W. ANOTHER MID-LEVEL TROUGH OVER
EASTERN CANADA IS FORECAST TO GRADUALLY RELINQUISH ITS INFLUENCE ON THE GREAT
LAKES REGION AND NEW ENGLAND, WITH LINGERING RELATIVELY COOL WEATHER
CONDITIONS. A HIGHLY ANOMALOUS MID-LEVEL RIDGE AND WELL ABOVE NORMAL 500-HPA
HEIGHTS ARE FORECAST OVER THE NORTHERN PACIFIC, BERING SEA, AND WESTERN ALASKA,
WITH THE MANUAL HEIGHT BLEND PREDICTING MAXIMUM POSITIVE HEIGHT ANOMALIES OF
+330 TO +360 METERS. WEAK TROUGHING IS DEPICTED DOWNSTREAM OVER MOST OF THE
REMAINDER OF ALASKA. FOR THE LOWER 48 STATES, THE DEEP ANOMALOUS TROUGH
FORECAST OFF THE U.S. WEST COAST IS EXPECTED TO EXTEND EASTWARD INTO MUCH OF
THE INTERMOUNTAIN WEST, FAVORING WIDESPREAD ONSHORE FLOW. FOR SOUTHERN
CALIFORNIA, THE SOUTHWEST, AND AREAS EAST OF THE CONTINENTAL DIVIDE, WEAK TO
MODERATE POSITIVE HEIGHT ANOMALIES ARE DEPICTED ASSOCIATED WITH MID-LEVEL
RIDGING. SHORT- WAVE TROUGHS EJECTING FROM THE LONG-WAVE TROUGH NEAR THE WEST
COAST WILL HELP MAINTAIN A VERY PROGRESSIVE CIRCULATION PATTERN OVER THE
CONTIGUOUS U.S. (CONUS), AS TRANSLATING NORTHERN STREAM DISTURBANCES UNDERMINE
THE ABILITY OF ANOMALOUS RIDGING TO STRENGTHEN DOWNSTREAM. IN THE CENTRAL
PACIFIC, WEAK POSITIVE HEIGHT ANOMALIES ARE FORECAST OVER THE HAWAIIAN ISLANDS.
ABOVE NORMAL TEMPERATURES ARE FAVORED OVER MUCH OF THE LOWER 48 STATES
ASSOCIATED WITH PREDICTED WEAK TO MODERATE ANOMALOUS RIDGING. PROBABILITIES
FAVORING ABOVE NORMAL TEMPERATURES EXCEED 70 PERCENT OVER PARTS OF THE
SOUTH-CENTRAL CONUS. FOR THE REMAINDER OF THE CONUS, WHICH INCLUDES MUCH OF THE
WEST, AND FROM PORTIONS OF THE DAKOTAS AND NEBRASKA EASTWARD TO THE NEW ENGLAND
COAST, NEAR TO BELOW NORMAL TEMPERATURES ARE FAVORED. THIS IS SUPPORTED BY THE
REFORECAST-CALIBRATED TEMPERATURE TOOLS AND CONSISTENT WITH THE OVERALL
SYNOPTIC PATTERN. FOR ALASKA, ABOVE NORMAL TEMPERATURES ARE FAVORED OVER THE
ALEUTIANS AND PARTS OF THE FAR WESTERN AND NORTHWESTERN MAINLAND, IN PROXIMITY
TO THE STRONG BERING SEA RIDGE. IN CONTRAST, BELOW NORMAL TEMPERATURES ARE
FAVORED OVER THE CENTRAL AND EASTERN ALASKAN INTERIOR AND PORTIONS OF THE
PANHANDLE REGION DUE TO PREDICTED EASTERLY SURFACE FLOW. IN HAWAII, ABOVE
NORMAL TEMPERATURES ARE STRONGLY FAVORED BASED ON A CONSOLIDATION OF TOOLS AND
THE AUTO BLEND.
ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS MOST OF THE CONUS DURING THE 6-10
DAY OUTLOOK PERIOD. IN THE WEST, THIS IS ATTRIBUTED TO MID-LEVEL TROUGHING AND
ENHANCED ONSHORE FLOW. NEARLY ALL PRECIPITATION GUIDANCE (INCLUDING THE
INTEGRATED VAPOR TRANSPORT (IVT) TOOLS FROM THE GEFS AND ECENS) PREDICTS
WETTER-THAN-NORMAL CONDITIONS MAY EXTEND THE ENTIRE LENGTH OF THE WEST COAST,
FROM WASHINGTON TO CALIFORNIA AND EVEN INTO PARTS OF WESTERN ARIZONA. MAXIMUM
PROBABILITIES OF 70-80% FAVORING ABOVE NORMAL PRECIPITATION ARE DEPICTED FOR
NORTH-CENTRAL CALIFORNIA. THE BROAD AREA OF FAVORED ABOVE NORMAL PRECIPITATION
ASSOCIATED WITH THE ACTIVE EASTERN PACIFIC TROUGH IS FORECAST TO AFFECT MOST
AREAS WEST OF THE CONTINENTAL DIVIDE. EAST OF THE DIVIDE, INCREASING GULF
MOISTURE ASSOCIATED WITH THE RETURN FLOW AROUND A SURFACE ANTICYCLONE PREDICTED
OFF THE SOUTHEAST COAST FAVORS ABOVE NORMAL PRECIPITATION FOR MOST OF THE
CENTRAL AND EASTERN CONUS, RESULTING IN AN EXTENDED PERIOD OF STORMINESS AND
MULTIPLE DISTURBANCES. A WEAK TILT TOWARDS BELOW NORMAL PRECIPITATION IS
INDICATED FOR SOUTHEASTERN ARIZONA, NEW MEXICO, AND MUCH OF TEXAS, LIKELY TOO
FAR FROM LARGE-SCALE STORM TRACKS. IN ALASKA, MOST PRECIPITATION TOOLS FAVOR
ABOVE NORMAL PRECIPITATION ACROSS ALL BUT SOUTHERNMOST PORTIONS OF THE
MAINLAND, THE ALASKA PENINSULA, ALEUTIANS, AND PANHANDLE REGION WHERE NEAR TO
BELOW NORMAL PRECIPITATION IS FAVORED. IN HAWAII, A MIX OF BELOW, NEAR, AND
ABOVE NORMAL PRECIPITATION IS FAVORED OVER THE ISLAND CHAIN, BASED ON A
CONSOLIDATION OF TOOLS AND THE AUTOBLEND.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 0Z 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. VERY
GOOD AGREEMENT IN THE MODEL HEIGHT FORECASTS IS OFFSET BY INCREASED UNCERTAINTY
IN THE SURFACE TEMPERATURE AND PRECIPITATION OUTLOOKS ESPECIALLY IN ALASKA.
8-14 DAY OUTLOOK FOR APR 01 - 07 2025
THE ENSEMBLE MEAN MODELS ARE IN GOOD AGREEMENT REGARDING THE WEEK-2 MEAN
CIRCULATION PATTERN. THE AMPLITUDES OF THE MID-LEVEL RIDGE CENTERED NEAR THE
ALEUTIANS AND OF THE MID-LEVEL TROUGH OVER THE EASTERN PACIFIC ARE FORECAST TO
BE REDUCED BY ABOUT 50% RELATIVE TO THE 6-10 DAY PERIOD. HOWEVER, THESE TWO
CIRCULATION FEATURES ARE STILL OF MODERATE TO STRONG INTENSITY. THE 500-HPA
LONG-WAVE TROUGH IS PREDICTED TO PROPAGATE A BIT TO THE NORTHEAST ON THE MANUAL
HEIGHT BLEND, WITH MAXIMUM NEGATIVE HEIGHT ANOMALIES CENTERED NEAR 45N/135W.
DOWNSTREAM OVER THE CONUS, POSITIVE 500-HPA HEIGHT ANOMALIES ARE FAVORED OVER
SOUTHERN CALIFORNIA, THE SOUTHWEST, AND FROM MOST OF THE GREAT PLAINS EASTWARD
TO THE ATLANTIC COAST. VARIATIONS AMONG THE THREE ENSEMBLES IN THE PREDICTED
STRENGTH OF THIS ANOMALOUS MID-LEVEL RIDGING AVERAGE OUT MAXIMUM HEIGHT
DEPARTURES OF +60 TO +90 METERS ACROSS MUCH OF THE SOUTHERN AND EASTERN CONUS.
IN THE CENTRAL PACIFIC, WEAK POSITIVE HEIGHT ANOMALIES ARE FORECAST OVER THE
HAWAIIAN ISLANDS.
THE WEEK-2 TEMPERATURE OUTLOOK FAVORS INCREASED SPATIAL COVERAGE OF BELOW
NORMAL TEMPERATURES OVER THE WESTERN LOWER 48 STATES AND ALASKA, AND INCREASED
COVERAGE OF ABOVE NORMAL TEMPERATURES OVER THE NORTH-CENTRAL AND NORTHEASTERN
CONUS RELATIVE TO THE EARLIER 6-10 DAY PERIOD. THE FAVORED BELOW NORMAL
TEMPERATURES IN THE WESTERN CONUS IS CONSISTENT WITH BIAS-CORRECTED AND RAW
TEMPERATURE GUIDANCE, WITH SLIGHTLY DIMINISHED SUPPORT FROM THE
REFORECAST-CALIBRATED TOOLS. IT IS ALSO CONSISTENT WITH THE APPROACHING
MID-LEVEL TROUGH FROM THE EASTERN PACIFIC AND INCREASED ONSHORE FLOW, WITH
INCREASED PRECIPITATION FORECAST AND AN EXTENDED PERIOD OF CLOUD COVER. IN
ALASKA, THE BELOW NORMAL TEMPERATURES ARE ASSOCIATED WITH ENHANCED EASTERLY
FLOW DUE TO SURFACE LOW PRESSURE OVER THE GULF OF ALASKA. OVER THE
NORTH-CENTRAL AND NORTHEASTERN LOWER 48 STATES, THE PREDICTED INCREASE IN
COVERAGE OF FAVORED ABOVE NORMAL TEMPERATURES IS RELATED TO THE DEPARTURE OF
THE MID-LEVEL TROUGH AND ASSOCIATED LOWER 500-HPA HEIGHTS OVER EASTERN CANADA.
THIS IS SUPPORTED BY THE REFORECAST-CALIBRATED TEMPERATURE TOOLS, BUT VERY FEW
OF THE BIAS-CORRECTED AND RAW TEMPERATURE TOOLS WHICH DEPICT A COLDER SOLUTION.
IT IS THOUGHT THAT AT LEAST THE BIAS-CORRECTED TEMPERATURE TOOLS MAY BE HOLDING
ON TO THE OLDER (COLDER) PATTERN TOO LONG, WHILE THE REFORECAST TEMPERATURES
ARE MORE IN SYNC WITH THE LATEST PREDICTED CHANGES OF THE CIRCULATION PATTERN.
HOWEVER, THESE DIFFERING TEMPERATURE TOOLS ARE ALSO CONSIDERED AGAINST THE
BACKDROP OF INCREASED SHORT WAVE ACTIVITY (AND THEREFORE MORE CHANGEABLE
WEATHER) RELATED TO THE EASTERN PACIFIC LONGWAVE TROUGH WHICH MAY MITIGATE
TEMPERATURES A BIT. BASED ON THESE CONSIDERATIONS, IT WAS DECIDED TO INCREASE
THE COVERAGE OF ABOVE NORMAL TEMPERATURES ACROSS THE NORTH-CENTRAL AND
NORTHEASTERN STATES, BUT WITH REDUCED PROBABILITIES COMPARED TO THE
AUTO-TEMPERATURE AND CONSOLIDATED FORECASTS. FOR HAWAII, ABOVE NORMAL
TEMPERATURES REMAIN FAVORED IN WEEK-2, BASED ON A CONSOLIDATION OF TOOLS AND
THE AUTO BLEND.
THE WEEK-2 PRECIPITATION OUTLOOK FAVORS ABOVE NORMAL PRECIPITATION OVER MOST
AREAS WEST OF THE CONTINENTAL DIVIDE, UNDER THE CONTINUING INFLUENCE OF A
LARGE, MID-LEVEL TROUGH. EAST OF THE DIVIDE, THERE IS A WEAK TILT IN THE ODDS
FOR ABOVE NORMAL PRECIPITATION FROM THE NORTHERN PLAINS EAST-SOUTHEASTWARD TO
THE ATLANTIC SEABOARD, FROM MAINE TO THE DELMARVA PENINSULA. THIS IS CONGRUENT
WITH MOST OF THE PRECIPITATION GUIDANCE. BELOW NORMAL PRECIPITATION IS FAVORED
IN AREAS WELL REMOVED FROM PRINCIPAL STORM TRACKS, AND INCLUDES PARTS OF THE
SOUTHERN ROCKIES AND ADJACENT HIGH PLAINS, AND MUCH OF THE SOUTHEAST. IN
ALASKA, THE MAJORITY OF OBJECTIVE GUIDANCE FAVORS A SIMILAR PRECIPITATION
PATTERN TO THAT OF THE EARLIER 6-10 DAY PERIOD, WITH FAVORED ABOVE NORMAL
PRECIPITATION OVER MOST OF THE MAINLAND, AND FAVORED NEAR TO BELOW NORMAL
PRECIPITATION FOR THE FAR SOUTHERN PART OF THE MAINLAND, THE ALASKA PENINSULA
AND ALEUTIANS, AND PARTS OF THE PANHANDLE REGION. IN HAWAII, ABOVE NORMAL
PRECIPITATION IS FAVORED FOR ALL OF THE ISLANDS EXCEPT THE BIG ISLAND WHERE
NEAR NORMAL PRECIPITATION IS FAVORED, BASED ON A CONSOLIDATION OF TOOLS AND THE
AUTO BLEND.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 0Z 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: NEAR AVERAGE, 3 OUT OF 5, DUE TO
GOOD OVERALL AGREEMENT AMONG MODEL HEIGHT FORECASTS OFFSET BY SIGNIFICANT
UNCERTAINTY IN THE SURFACE TEMPERATURE AND PRECIPITATION FIELDS, ESPECIALLY FOR
ALASKA.
FORECASTER: ANTHONY A
NOTES:
AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OCCASIONALLY MANUAL
INTERVENTION IS NECESSARY TO ADDRESS QUALITY CONTROL AND CONSISTENCY ISSUES. IN
THESE CASES, FORECASTS ARE MANUALLY DRAWN BUT A FULL DISCUSSION IS NOT ISSUED.
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 (UNSHADED, "N"). HISTORICAL AVERAGE
VALUES FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "F"). 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 (UNSHADED, "N"). HISTORICAL MEDIAN VALUES
FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "INCHES"). 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
APRIL 17.
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:
19590401 - 20000316 - 19700407 - 19760319 - 19930319
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:
19590401 - 19700406 - 19930319 - 20000315 - 19880321
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 30 - APR 03, 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON B A NRN CALIF B A
SRN CALIF N A IDAHO N A NEVADA N A
W MONTANA N 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 N A
NEBRASKA A A KANSAS A N OKLAHOMA A N
N TEXAS A N S TEXAS A B W TEXAS A B
MINNESOTA B A IOWA N A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN B A
ILLINOIS N A MISSISSIPPI A A MICHIGAN B A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT B A NEW HAMP N A MAINE B A
MASS N A CONN N A RHODE IS N A
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A A VIRGINIA A A
N CAROLINA A A S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A N AK N SLOPE A A
AK ALEUTIAN N B AK WESTERN N A AK INT BSN B A
AK S INT B N AK SO COAST N N AK PNHDL N N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 01 - 07 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO B A NEVADA B A
W MONTANA B A E MONTANA A A WYOMING A A
UTAH A A ARIZONA A B COLORADO A N
NEW MEXICO A B N DAKOTA A A S DAKOTA A A
NEBRASKA A N KANSAS A N OKLAHOMA A N
N TEXAS A N S TEXAS A N W TEXAS A B
MINNESOTA A A IOWA A A MISSOURI A N
ARKANSAS A B LOUISIANA A B WISCONSIN A A
ILLINOIS A A MISSISSIPPI A B MICHIGAN A 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 A MAINE B A
MASS N A CONN N A RHODE IS N A
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA A N GEORGIA A B
FL PNHDL A B FL PENIN A B AK N SLOPE B A
AK ALEUTIAN N N AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B N 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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