610
FXUS06 KWBC 241937
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU APRIL 24 2025
6-10 DAY OUTLOOK FOR APR 30 - MAY 04, 2025
MODEL ENSEMBLE MEANS (GEFS, ECMWF, AND CANADIAN) ARE IN GOOD AGREEMENT WITH A
PROGRESSIVE FLOW PATTERN OVER THE CONTIGUOUS U.S. (CONUS) FROM THE END OF APRIL
THROUGH THE BEGINNING OF MAY. A 500-HPA TROUGH IS FORECAST TO SHIFT EASTWARD
FROM THE GREAT PLAINS TO THE EASTERN CONUS, WHILE AN AMPLIFIED MID-LEVEL RIDGE
PROGRESSES ACROSS THE WEST AND IS CENTERED ACROSS THE NORTHERN GREAT PLAINS BY
DAY 10. FOR THIS 5-DAY PERIOD, THE MANUAL 500-HPA HEIGHT BLEND DEPICTS POSITIVE
500-HPA HEIGHT ANOMALIES FOR NEARLY ALL OF THE CONUS AND AN INCREASED CHANCE OF
ABOVE-NORMAL TEMPERATURES FOR MOST AREAS. A TROUGH CONTINUES TO BE FORECAST
ACROSS WESTERN ALASKA AND EXTENDING INTO THE GULF OF ALASKA IN THE 6-10 DAY
PERIOD, WITH ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES ACROSS THE STATE.
ABOVE-NORMAL TEMPERATURE PROBABILITIES EXCEED 70 PERCENT FOR THE NORTHERN HIGH
PLAINS, UNDER THE CENTER OF A PREDICTED RIDGE. ANOMALOUS POSITIVE TEMPERATURE
ANOMALIES ARE PREDICTED OVER THE SOUTHEASTERN CONUS FOR THE FIRST HALF OF THE
6-10 DAY FORECAST PERIOD. NEAR TO BELOW-NORMAL TEMPERATURES ARE FORECAST OVER
NORTHEASTERN AREAS OF THE CONUS, UNDER THE PREDICTED TROUGH THAT PROGRESSES
OVER THE EAST DURING THE PERIOD. NEAR NORMAL TEMPERATURES ARE FAVORED FOR PARTS
OF THE SOUTHWEST AND SOUTHERN GREAT PLAINS DUE TO LOWER 500-HPA HEIGHTS AND
INCREASING PROBABILITIES OF PRECIPITATION. BELOW-NORMAL TEMPERATURES ARE LIKELY
FOR MUCH OF NORTHERN ALASKA UNDER PREDICTED NEGATIVE 500-HPA HEIGHT ANOMALIES.
NEAR-NORMAL TEMPERATURES ARE FAVORED FOR SOUTHERN MAINLAND ALASKA AND SOUTHEAST
ALASKA, UNDER SOUTHERLY MID-LEVEL FLOW. ABOVE-NORMAL TEMPERATURES ARE LIKELY
FOR HAWAII, WITH POSITIVE SURROUNDING SEA SURFACE TEMPERATURE ANOMALIES.
ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS SOUTHERN AND CENTRAL MAINLAND
ALASKA WITH PROBABILITIES EXCEEDING 50 PERCENT FOR SOUTHEAST ALASKA, AHEAD OF A
PREDICTED TROUGH AND SOUTHERLY FLOW. WITH THE PROGRESSIVE MID-LEVEL CIRCULATION
PATTERN FORECAST FOR THE CONUS, ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS
MOST OF THE SOUTHERN CONUS. INCREASING CHANCES OF ABOVE-NORMAL PRECIPITATION
ARE FORECAST FOR THE SOUTHWESTERN CONUS WITH A SHORTWAVE TROUGH MOVING INTO THE
SOUTHWEST DURING THE PERIOD. PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION
EXCEED 50 PERCENT FOR PARTS OF THE SOUTHERN PLAINS. ABOVE-NORMAL PRECIPITATION
IS FAVORED FOR THE ENTIRE EAST COAST, WITH THE PASSAGE OF A FRONT.
NEAR-TO-BELOW NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF THE NORTHERN
CONUS, UNDER THE DEVELOPING RIDGE. DYNAMICAL MODEL FORECASTS FAVOR ABOVE-NORMAL
PRECIPITATION FOR HAWAII.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 25% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 35% 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 ON THE PROGRESSIVE CIRCULATION PATTERN, OFFSET BY SOME
AREAS OF DISAGREEMENT AMONG FORECAST TOOLS.
8-14 DAY OUTLOOK FOR MAY 02 - 08 2025
ENSEMBLE MEANS FORECAST A CONTINUED PROGRESSIVE PATTERN DURING THE WEEK-2
PERIOD. A PREDICTED RIDGE AMPLIFIES OVER THE NORTHERN CENTRAL CONUS DURING THE
PERIOD AND POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST ACROSS THE NORTHEAST
AFTER THE PASSAGE OF A TROUGH. A TROUGH AND ASSOCIATED NEGATIVE 500-HPA HEIGHT
ANOMALIES PERSIST ACROSS ALASKA AND EXTEND SOUTHWARD ALONG THE WEST COAST OF
NORTH AMERICA LATER IN THE PERIOD.
ABOVE-NORMAL TEMPERATURES CONTINUE TO BE FAVORED ACROSS MOST OF THE CONUS IN
THE WEEK-2 PERIOD. PROBABILITIES EXCEED 70 PERCENT FOR PARTS OF THE NORTHERN
PLAINS AS THE RIDGE AMPLIFIES OVER THIS REGION. ABOVE-NORMAL TEMPERATURES ARE
SLIGHTLY FAVORED FOR MUCH OF THE EAST UNDER MEAN POSITIVE 500-HPA HEIGHT
ANOMALIES. NEAR TO BELOW-NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE
SOUTHWEST, SOUTHERN PLAINS, AND LOWER MISSISSIPPI VALLEY, WITH PREDICTED
NEAR-AVERAGE MID-LEVEL HEIGHTS AND ENHANCED PRECIPITATION. BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR NORTHWESTERN AND NORTHERN MAINLAND ALASKA UNDER
NEGATIVE 500-HPA HEIGHT ANOMALIES. ABOVE-NORMAL TEMPERATURES ARE PREDICTED TO
PERSIST ACROSS HAWAII DURING WEEK-2.
SIMILAR TO THE 6-10 DAY PERIOD, ABOVE-NORMAL PRECIPITATION IS FAVORED FOR MOST
OF MAINLAND ALASKA, EXCLUDING THE WEST AND NORTH COASTS, AND FAVORED FOR
SOUTHEAST ALASKA, AHEAD OF PREDICTED TROUGHS. ABOVE-NORMAL PRECIPITATION
CONTINUES TO BE FAVORED FOR MUCH OF THE SOUTHWESTERN CONUS INTO THE SOUTHERN
PLAINS, WITH A PREDICTED TROUGH DEVELOPING OVER THE REGION. ABOVE-NORMAL
PRECIPITATION IS ALSO FAVORED FOR THE GULF AND SOUTHERN ATLANTIC COASTS,
SUPPORTED BY MOST DYNAMICAL MODEL FORECAST TOOLS. DYNAMICAL MODELS CONTINUE TO
PREDICT FAVORED ABOVE-NORMAL PRECIPITATION FOR HAWAII DURING THE WEEK-2 PERIOD.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 25% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 35% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE MEAN DYNAMICAL MODEL HEIGHT FORECASTS AND SURFACE
TOOLS FOR MOST AREAS, OFFSET BY UNCERTAINTY DUE TO AN EVOLVING PATTERN.
FORECASTER: DAN COLLINS
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 MAY
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:
19540422 - 19810407 - 20020420 - 20080416 - 19640420
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:
20020421 - 19540419 - 19810407 - 20080415 - 20020416
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 30 - MAY 04, 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON A N NRN CALIF A N
SRN CALIF A A IDAHO A N NEVADA A A
W MONTANA A N E MONTANA A N WYOMING A N
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 N A
N TEXAS A A S TEXAS A A W TEXAS N A
MINNESOTA A N IOWA A N MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN N N
ILLINOIS N N MISSISSIPPI A A MICHIGAN B N
INDIANA N N OHIO N A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK N N
VERMONT N N NEW HAMP N N MAINE N A
MASS N A CONN A A RHODE IS A 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 A AK N SLOPE B N
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A
AK S INT N A AK SO COAST N A AK PNHDL N A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 02 - 08 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON A N NRN CALIF A N
SRN CALIF A A IDAHO A N NEVADA A A
W MONTANA A N E MONTANA A N WYOMING A N
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 N A
N TEXAS N A S TEXAS N A W TEXAS B A
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS N N LOUISIANA A A WISCONSIN A N
ILLINOIS A N MISSISSIPPI N A MICHIGAN A N
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE N N ALABAMA N N NEW YORK A N
VERMONT A N NEW HAMP A N MAINE A N
MASS A N CONN A N RHODE IS A N
PENN A N NEW JERSEY A N W VIRGINIA A N
MARYLAND A N DELAWARE A A VIRGINIA A N
N CAROLINA A A S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN N A AK N SLOPE B N
AK ALEUTIAN B N AK WESTERN B N AK INT BSN B A
AK S INT N A AK SO COAST N A AK PNHDL N A
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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