082  
FXUS06 KWBC 012001  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT THU MAY 01 2025  
 
6-10 DAY OUTLOOK FOR MAY 07 - 11 2025  
 
DYNAMICAL MODELS ARE IN GOOD AGREEMENT REGARDING THE 500-HPA HEIGHT PATTERN  
ACROSS NORTH AMERICA AND THE SURROUNDING REGION. A BROAD AREA OF POSITIVE  
500-HPA HEIGHT ANOMALIES IS FORECAST FOR THE WESTERN CONTIGUOUS U.S. (CONUS)  
AND ACROSS THE NORTHERN TIER AND SOUTHERN CANADA INTO EASTERN NORTH AMERICA. AN  
AREA OF NEGATIVE ANOMALIES AND MID-LEVEL TROUGHING IS FORECAST TO UNDERCUT THE  
RIDGE ACROSS THE SOUTHEASTERN CONUS. NEGATIVE 500-HPA HEIGHT ANOMALIES ARE  
FORECAST ACROSS THE GULF OF ALASKA AND MUCH OF THE SOUTH COAST AND THE SOUTHERN  
MAINLAND. HOWEVER, WITH NEAR TO BELOW NORMAL HEIGHTS FAVORED ACROSS THE  
REMAINDER OF ALASKA, THIS FAVORS INCREASED ONSHORE FLOW TO PARTS OF SOUTHEAST  
ALASKA.  
 
ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH OF THE CONUS TODAY, EXCLUDING  
PORTIONS OF THE SOUTH-CENTRAL AND SOUTHEASTERN CONUS. STRONG POSITIVE MID-LEVEL  
HEIGHT ANOMALIES BRING ELEVATED CHANCES FOR ABOVE-NORMAL TEMPERATURES TO MUCH  
OF THE WEST, NORTH-CENTRAL, AND NORTHEASTERN CONUS. MEANWHILE, A SHORTWAVE  
TROUGH PROGRESSING ACROSS THE SOUTHERN TIER WILL BRING INCREASED PRECIPITATION  
AND CLOUDINESS, BRINGING ENHANCED CHANCES FOR BELOW NORMAL TEMPERATURES TO THE  
SOUTH-CENTRAL CONUS. IN ALASKA, ABOVE-NORMAL IS FAVORED FOR PORTIONS OF  
SOUTHWEST ALASKA AND THE ALEUTIANS. BELOW NORMAL TEMPERATURES ARE SLIGHTLY  
FAVORED FOR PORTIONS OF NORTHERN AND EASTERN MAINLAND ALASKA INTO SOUTHEAST  
ALASKA, WITH NEAR NORMAL FAVORED FOR THE REMAINDER OF MAINLAND ALASKA. IN  
HAWAII, ABOVE NORMAL TEMPERATURES REMAIN FAVORED FOR THE ISLAND CHAIN.  
 
ABOVE NORMAL PRECIPITATION IS FAVORED FOR MUCH OF THE FOUR CORNERS, SOUTHERN  
PLAINS, AND THE SOUTHEASTERN CONUS AS RESULT OF A SHORTWAVE TROUGH PROGRESSING  
ACROSS THE SOUTHERN TIER. BELOW NORMAL PRECIPITATION IS FAVORED BENEATH THE  
MID-LEVEL RIDGING AND POSITIVE 500-HPA HEIGHT ANOMALIES ACROSS THE NORTHERN  
TIER OF THE CONUS AND ALONG MUCH OF THE WEST COAST. ABOVE NORMAL PRECIPITATION  
IS FAVORED FOR SOUTHEASTERN ALASKA, WITH ONSHORE FLOW BRINGING ENHANCED  
PROBABILITIES TO SOUTHEAST ALASKA IN PARTICULAR. A SLIGHT TILT TOWARD BELOW  
NORMAL PRECIPITATION IS FAVORED ALONG PARTS OF THE NORTH SLOPE. IN HAWAII,  
ABOVE-NORMAL PRECIPITATION CHANCES ARE ELEVATED WITH GOOD AGREEMENT AMONG THE  
DYNAMICAL GUIDANCE.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 10% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 25% 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  
FAIRLY GOOD AGREEMENT IN THE MODEL HEIGHT PATTERN.  
 
8-14 DAY OUTLOOK FOR MAY 09 - 15 2025  
 
THE DYNAMICAL MODELS REMAIN IN GOOD AGREEMENT HEADING INTO THE WEEK-2 PERIOD.  
POSITIVE 500-HPA HEIGHT ANOMALIES REMAIN FORECAST ACROSS THE NORTHERN CONUS,  
WITH MOST GUIDANCE FAVORING ABOVE NORMAL HEIGHTS ACROSS THE WEST FOR THE WEEK-2  
MEAN, AS WELL. NEAR TO SLIGHTLY BELOW NORMAL HEIGHTS ARE AGAIN FAVORED FOR THE  
SOUTHEASTERN CONUS WITH A SHORTWAVE TROUGH PUSHING THROUGH THE REGION. IN  
ALASKA, MOST GUIDANCE FORECASTS NEAR NORMAL HEIGHTS FOR WEEK-2 WITH WEAK  
TROUGHING FAVORED IN THE BERING SEA AND THE ALEUTIAN ISLANDS.  
 
AS WITH THE 6-10 DAY PERIOD, ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH  
OF THE CONUS DURING WEEK-2, EXCLUDING THE SOUTH-CENTRAL AND SOUTHEASTERN CONUS.  
POSITIVE MID-LEVEL HEIGHT ANOMALIES BRING ELEVATED CHANCES FOR ABOVE NORMAL  
TEMPERATURES TO MUCH OF THE WEST, NORTH-CENTRAL AND NORTHEASTERN CONUS.  
MEANWHILE, A SHORTWAVE TROUGH PROGRESSING ACROSS THE SOUTHERN TIER IS  
ASSOCIATED WITH ENHANCED CHANCES FOR BELOW NORMAL TEMPERATURES FOR MUCH OF THE  
REGION. IN ALASKA, ABOVE NORMAL IS FAVORED FOR MUCH OF THE SOUTHWESTERN  
PORTIONS OF THE STATE WITH A SLIGHT TILT TOWARDS BELOW NORMAL ALONG THE NORTH  
SLOPE. IN HAWAII, ABOVE NORMAL TEMPERATURES REMAIN FAVORED FOR THE ISLAND CHAIN.  
 
ABOVE NORMAL PRECIPITATION REMAINS FAVORED FOR PORTIONS OF THE GREAT BASIN,  
FOUR CORNERS, SOUTHERN PLAINS, AND THE SOUTHEASTERN CONUS AS RESULT OF A  
SHORTWAVE TROUGH PROGRESSING ACROSS THE SOUTHERN TIER. BELOW NORMAL  
PRECIPITATION IS FAVORED BENEATH THE MID-LEVEL RIDGING AND POSITIVE 500-HPA  
HEIGHT ANOMALIES ACROSS THE UPPER MISSISSIPPI VALLEY AND ADJACENT AREAS OF THE  
GREAT PLAINS EASTWARD TO THE GREAT LAKES AND INTERIOR NORTHEAST. NEAR NORMAL  
PRECIPITATION IS FAVORED FOR PORTIONS OF THE NORTHWESTERN CONUS WITH SLIGHTLY  
MORE ONSHORE FLOW INTO THE REGION RELATIVE TO THE 6-10 DAY PERIOD. ABOVE NORMAL  
PRECIPITATION IS FAVORED FOR THE SOUTHERN PORTIONS OF ALASKA, WITH ONSHORE FLOW  
BRINGING ENHANCED PROBABILITIES TO SOUTHEAST ALASKA IN PARTICULAR. A SLIGHT  
TILT TOWARD BELOW NORMAL PRECIPITATION IS FAVORED ALONG THE WEST COAST OF  
MAINLAND ALASKA. IN HAWAII, ABOVE-NORMAL PRECIPITATION CHANCES ARE FAVORED FOR  
MUCH OF THE STATE, EXCLUDING THE BIG ISLAND, WITH GOOD AGREEMENT AMONG THE  
DYNAMICAL GUIDANCE.  
 
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: ABOVE AVERAGE, 4 OUT OF 5. VERY  
GOOD AGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION DYNAMICAL AND  
STATISTICAL TOOLS IS OFFSET BY DIFFERENCES IN ENSEMBLE MEAN 500-HPA HEIGHT  
ANOMALIES.  
 
FORECASTER: RYAN BOLT  
 
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:  
19560513 - 20040422 - 19660424 - 19820425 - 19940411  
 
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:  
19640410 - 20040421 - 19660425 - 19560513 - 19610514  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR MAY 07 - 11 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A B OREGON A N NRN CALIF A N  
SRN CALIF A N IDAHO A N NEVADA A N  
W MONTANA A B E MONTANA A B WYOMING A N  
UTAH A A ARIZONA A A COLORADO B A  
NEW MEXICO B A N DAKOTA A B S DAKOTA A B  
NEBRASKA A N KANSAS N A OKLAHOMA B A  
N TEXAS B A S TEXAS B A W TEXAS B A  
MINNESOTA A B IOWA A B MISSOURI N N  
ARKANSAS N A LOUISIANA N A WISCONSIN A B  
ILLINOIS A B MISSISSIPPI N A MICHIGAN A B  
INDIANA A B OHIO A B KENTUCKY A N  
TENNESSEE N A ALABAMA N A 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 N 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 A N AK WESTERN N N AK INT BSN N N  
AK S INT N A AK SO COAST N A AK PNHDL B A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR MAY 09 - 15 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A N OREGON A N NRN CALIF A N  
SRN CALIF A N IDAHO A A NEVADA A A  
W MONTANA A N E MONTANA A N WYOMING A A  
UTAH A A ARIZONA A N COLORADO A A  
NEW MEXICO B A N DAKOTA A B S DAKOTA A N  
NEBRASKA A N KANSAS N N OKLAHOMA B N  
N TEXAS B A S TEXAS B A W TEXAS B A  
MINNESOTA A B IOWA A B MISSOURI N B  
ARKANSAS B N LOUISIANA B A WISCONSIN A B  
ILLINOIS A B MISSISSIPPI B A MICHIGAN A B  
INDIANA A B OHIO A B KENTUCKY N N  
TENNESSEE N N ALABAMA B A NEW YORK A B  
VERMONT A B 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 N VIRGINIA A A  
N CAROLINA A A S CAROLINA N A GEORGIA N A  
FL PNHDL N A FL PENIN N A AK N SLOPE B N  
AK ALEUTIAN A N AK WESTERN A N AK INT BSN N N  
AK S INT A A AK SO COAST A 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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