358
FXUS06 KWBC 281917
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON APRIL 28 2025
6-10 DAY OUTLOOK FOR MAY 04 - 08 2025
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA
CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING THE
6-10 DAY PERIOD. THE MANUAL 500-HPA HEIGHT BLEND IS BASED PRIMARILY ON THE
ENSEMBLE MEANS FROM THE GEFS, ECMWF AND CANADIAN MODELS DUE TO RECENT MODEL
SKILL. THE RESULTANT MANUAL BLEND FEATURES AN AMPLIFIED MID-LEVEL RIDGE AND
ABOVE-NORMAL HEIGHTS OVER MUCH OF THE NORTHEASTERN CONTIGUOUS U.S. (CONUS),
WHILE A MID-LEVEL 500-HPA TROUGH AND BELOW-NORMAL 500-HPA HEIGHTS ARE FORECAST
ACROSS THE SOUTHWESTERN CONUS. A TROUGH IS FORECAST ACROSS ALASKA, EXTENDING
INTO THE GULF OF ALASKA, WITH ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES
ACROSS THE STATE. RIDGING IS FORECAST OVER THE NORTH PACIFIC OCEAN AND THE
ALEUTIANS. SLIGHTLY ABOVE-NORMAL 500-HPA HEIGHTS ARE PREDICTED ACROSS HAWAII.
ENHANCED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER THE
NORTHERN ROCKIES AND NORTHERN PLAINS EXTENDING EASTWARD TO MOST OF THE CENTRAL
AND EASTERN CONUS (EXCEPT FOR SOUTHERN FLORIDA, WHERE BELOW NORMAL TEMPERATURES
ARE FAVORED DUE TO A PREDICTED WEAK TROUGH OVER THE REGION) UNDERNEATH
PREDOMINANT RIDGING AND ABOVE NORMAL 500-HPA HEIGHTS, SUPPORTED BY MOST OF THE
DYNAMICAL GUIDANCE. THE STRONGEST PROBABILITIES (>80%) ARE FORECAST ACROSS
PARTS OF THE NORTHERN PLAINS AND THE UPPER MISSISSIPPI VALLEY. ANOMALOUS
NEGATIVE TEMPERATURE ANOMALIES ARE PREDICTED OVER THE WESTERN AND SOUTHWESTERN
CONUS UNDER THE PREDICTED TROUGH THAT PROGRESSES OVER THE WEST DURING THE
PERIOD. BELOW-NORMAL TEMPERATURES ARE LIKELY FOR MUCH OF ALASKA (EXCEPT FOR THE
ALEUTIANS AND PARTS OF THE SOUTHWESTERN MAINLAND ALASKA, WHERE ABOVE-NORMAL
TEMPERATURES ARE FAVORED), UNDER PREDICTED NEGATIVE 500-HPA HEIGHT ANOMALIES.
ABOVE-NORMAL TEMPERATURES ARE LIKELY FOR HAWAII, WITH POSITIVE SURROUNDING SEA
SURFACE TEMPERATURE ANOMALIES, CONSISTENT WITH THE REFORECAST CONSOLIDATION
TEMPERATURE FORECAST TOOL.
WITH A MID-LEVEL TROUGH FORECAST TO PROGRESS ACROSS THE SOUTHWEST, ABOVE-NORMAL
PRECIPITATION IS FAVORED ACROSS THE WESTERN AND CENTRAL CONUS. BELOW-NORMAL
PRECIPITATION IS FAVORED ACROSS MUCH OF THE EASTERN CONUS UNDER AN AMPLIFIED
RIDGE AND ABOVE-NORMAL 500-HPA HEIGHTS. ABOVE-NORMAL PRECIPITATION IS FAVORED
FOR MOST OF FLORIDA AND THE GULF COAST DUE TO A WEAK TROUGH PREDICTED OVER THE
REGION. ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF SOUTHERN ALASKA,
AHEAD OF A PREDICTED TROUGH AND SOUTHERLY FLOW, WHILE NEAR OR BELOW-NORMAL
PRECIPITATION IS PREDICTED OVER PORTIONS OF NORTHERN MAINLAND ALASKA, SUPPORTED
BY MOST OF THE DYNAMICAL PRECIPITATION FORECAST TOOLS. PRECIPITATION
CONSOLIDATION TOOL FORECASTS FAVOR ABOVE-NORMAL PRECIPITATION FOR HAWAII.
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 ON THE PROGRESSIVE CIRCULATION PATTERN, OFFSET BY SOME
AREAS OF DISAGREEMENT AMONG FORECAST TOOLS.
8-14 DAY OUTLOOK FOR MAY 06 - 12 2025
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A FAIRLY CONSISTENT
500-HPA CIRCULATION PATTERN RELATIVE TO THE 6-10 DAY PERIOD ACROSS NORTH
AMERICA AND THE SURROUNDING REGIONS. A PREDICTED RIDGE AND POSITIVE 500-HPA
HEIGHT ANOMALIES ARE PREDICTED OVER MOST OF THE NORTHERN TIER OF THE CONS. A
WEAK TROUGH PROGRESSES EASTWARD OVER THE SOUTHWEST EARLY IN WEEK 2. ANOTHER
WEAK TROUGH IS FORECAST OVER FLORIDA. 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. SLIGHTLY BELOW-NORMAL 500-HPA
HEIGHTS ARE PREDICTED ACROSS HAWAIIAN ISLANDS.
ABOVE-NORMAL TEMPERATURES CONTINUE TO BE LIKELY ACROSS MOST OF THE NORTHERN AND
EASTERN CONUS IN THE WEEK-2 PERIOD, UNDER RIDGING AND POSITIVE 500-HPA HEIGHT
ANOMALIES. PROBABILITIES EXCEED 70 PERCENT FOR PARTS OF THE UPPER AND MIDDLE
MISSISSIPPI VALLEY AS THE RIDGE PERSISTS OVER THIS REGION. BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR PARTS OF SOUTHEASTERN NEW MEXICO, WESTERN TEXAS,
AND SOUTHERN FLORIDA WITH PREDICTED BELOW-AVERAGE MID-LEVEL HEIGHTS AND
ENHANCED PRECIPITATION. BELOW-NORMAL TEMPERATURES ARE FAVORED FOR THE NORTHERN
PART OF MAINLAND ALASKA, WHILE ABOVE-NORMAL TEMPERATURES ARE LIKELY OVER THE
ALEUTIANS AND SOUTHWESTERN MAINLAND ALASKA, CONSISTENT WITH MOST OF THE
DYNAMICAL TEMPERATURE FORECAST TOOLS. ABOVE-NORMAL TEMPERATURES ARE PREDICTED
TO PERSIST ACROSS HAWAII DURING WEEK-2 BY DYNAMICAL MODELS.
NEAR- TO ABOVE-NORMAL PRECIPITATION ARE FAVORED FOR MUCH OF THE WESTERN AND
CENTRAL CONUS AS WELL AS FLORIDA, SUPPORTED BY MOST DYNAMICAL MODEL
PRECIPITATION FORECAST TOOLS. NEAR TO BELOW-NORMAL PRECIPITATION IS SLIGHTLY
FAVORED OVER MUCH OF THE EASTERN CONUS, UNDER MEAN POSITIVE 500-HPA HEIGHT
ANOMALIES. SIMILAR TO THE 6-10 DAY PERIOD, ABOVE-NORMAL PRECIPITATION IS
FAVORED FOR MOST OF SOUTHERN MAINLAND ALASKA, EXCLUDING THE NORTH COASTS, AHEAD
OF A PREDICTED TROUGH. ABOVE-NORMAL PRECIPITATION IS FAVORED FOR HAWAII DURING
THE WEEK-2 PERIOD, CONSISTENT WITH THE PRECIPITATION CONSOLIDATION.
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: 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: LUKE H
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:
19570420 - 19670408 - 19640419 - 20040417 - 20060411
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:
19640421 - 20010407 - 19670407 - 19570422 - 20020417
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 04 - 08 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 A A E MONTANA A A WYOMING A A
UTAH B A ARIZONA B A COLORADO B A
NEW MEXICO B A N DAKOTA A A S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA A A
N TEXAS N A S TEXAS N A W TEXAS B A
MINNESOTA A A IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A B
ILLINOIS A B MISSISSIPPI A B MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY A B
TENNESSEE A B ALABAMA A B NEW YORK A B
VERMONT A B NEW HAMP A B MAINE A B
MASS A B CONN A B RHODE IS A B
PENN A B NEW JERSEY A B W VIRGINIA A B
MARYLAND A B DELAWARE A B VIRGINIA A B
N CAROLINA A B S CAROLINA A B GEORGIA A B
FL PNHDL A N FL PENIN B A AK N SLOPE B N
AK ALEUTIAN A A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 06 - 12 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N A NRN CALIF N A
SRN CALIF N N IDAHO A N NEVADA A N
W MONTANA A A E MONTANA A N WYOMING A N
UTAH A N ARIZONA N N COLORADO A A
NEW MEXICO B A N DAKOTA A A S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS B A W TEXAS B A
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS A N LOUISIANA A A WISCONSIN A B
ILLINOIS A B MISSISSIPPI A N MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY A B
TENNESSEE A B ALABAMA A N NEW YORK A B
VERMONT A N NEW HAMP A B MAINE A B
MASS A B CONN A B RHODE IS A B
PENN A B NEW JERSEY A B W VIRGINIA A B
MARYLAND A B DELAWARE A B VIRGINIA A B
N CAROLINA A B S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN B A AK N SLOPE B N
AK ALEUTIAN A A AK WESTERN N A AK INT BSN N N
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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page