839
FXUS06 KWBC 191902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED APRIL 19 2023
6-10 DAY OUTLOOK FOR APR 25 - 29 2023
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED AMPLIFIED
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 GFS, ECMWF, AND CANADIAN MODEL ENSEMBLES DUE TO RECENT
MODEL SKILL. THE RESULTANT MANUAL BLEND FEATURES ANOMALOUS MID-LEVEL TROUGHING
AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES OVER ALASKA. DOWNSTREAM
ANOMALOUS RIDGING IS FORECAST OVER THE ALASKA PANHANDLE AND THE WESTERN
CONTIGUOUS U.S. (CONUS), WHILE AN ANOMALOUS TROUGH WITH BELOW NORMAL 500-HPA
HEIGHTS IS SITUATED OVER THE CENTRAL AND EASTERN CONUS DURING THE 6-10 DAY
PERIOD IN MODEL SOLUTIONS.
ENHANCED CHANCES FOR BELOW-NORMAL TEMPERATURES ARE FAVORED OVER PARTS OF THE
GREAT PLAINS AND EASTERN HALF OF THE CONUS (EXCEPT FOR MAINE AND FLORIDA
PENINSULA, WHERE ABOVE-NORMAL TEMPERATURES ARE INDICATED) UNDER THE PREDICTED
ANOMALOUS MID-LEVEL TROUGH AND BELOW-NORMAL 500-HPA HEIGHTS. NEAR- TO
ABOVE-NORMAL TEMPERATURES ARE LIKELY OVER MUCH OF THE WESTERN CONUS ASSOCIATED
WITH ANOMALOUS RIDGING PREDICTED OVER THE REGION, CONSISTENT WITH THE GEFS
TEMPERATURE CALIBRATED REFORECAST TOOL. BELOW-NORMAL TEMPERATURES ARE FAVORED
FOR MAINLAND ALASKA UNDER BELOW NORMAL 500-HPA HEIGHTS AND NORTHWESTERLY FLOW
ALOFT, SUPPORTED BY MOST OF THE DYNAMICAL TEMPERATURE FORECAST TOOLS.
TROUGHING OVER THE CENTRAL AND EASTERN CONUS FAVORS ABOVE-NORMAL PRECIPITATION
OVER MUCH OF THE CENTRAL AND EASTERN CONUS. ODDS TILT TOWARDS BELOW-NORMAL
PRECIPITATION OVER THE WESTERN CONUS DUE TO A PREDICTED RIDGE OVER THE REGION,
SUPPORTED BY MOST PRECIPITATION FORECAST TOOLS. SURFACE LOW PRESSURE OVER THE
ALEUTIANS AND ANOMALOUS MID-LEVEL TROUGHING ARE PREDICTED BY MODEL GUIDANCE,
RESULTING IN ENHANCED PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION FOR ALASKA.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 40% OF TODAY'S GFS
SUPERENSEMBLE MEAN CENTERED ON DAY 8, 30% 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
MODEL AGREEMENT ON AN AMPLIFIED 500-HPA PATTERN ACROSS MUCH OF THE FORECAST
DOMAIN.
8-14 DAY OUTLOOK FOR APR 27 - MAY 03, 2023
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A FAIRLY PERSISTENT
500-HPA CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS.
ANOMALOUS MID-LEVEL TROUGHING WITH BELOW-NORMAL 500-HPA HEIGHTS IS SITUATED
OVER THE BERING SEA AND WESTERN MAINLAND ALASKA IN ENSEMBLE MEAN SOLUTIONS FROM
THE GEFS, ECMWF AND CANADIAN MODELS. AN ANOMALOUS 500-HPA TROUGH WITH BELOW
NORMAL 500-HPA HEIGHTS IS PREDICTED OVER THE CENTRAL AND EASTERN CONUS, WHILE
RIDGING AND SLIGHTLY POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER THE
WESTERN CONUS.
GUIDANCE FROM THE DYNAMICAL MODELS, REFORECAST TOOLS, AND OTHER TOOLS INDICATE
ENHANCED CHANCES FOR BELOW-NORMAL TEMPERATURES OVER PARTS OF THE NORTHERN AND
THE CENTRAL ROCKIES, THE GREAT PLAINS, AND MUCH OF THE EASTERN HALF OF THE
CONUS (EXCEPT FLORIDA WHERE ABOVE-NORMAL TEMPERATURES ARE INDICATED) DUE TO A
PREDICTED ANOMALOUS TROUGH WITH BELOW NORMAL 500-HPA HEIGHTS OVER THE REGION.
MEANWHILE, ENHANCED PROBABILITIES OF NEAR- TO ABOVE-NORMAL TEMPERATURES ARE
FAVORED OVER MUCH OF THE WESTERN CONUS UNDER PREDICTED WEAK ANOMALOUS RIDGING.
BELOW-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF ALASKA UNDER BELOW NORMAL
500-HPA HEIGHTS AND NORTHWESTERLY FLOW ALOFT, WITH THE EXCEPTION OF THE ALASKA
PANHANDLE WHERE ABOVE-NORMAL TEMPERATURES ARE MOST LIKELY UNDER ANOMALOUS
SOUTHERLY FLOW.
ANOMALOUS TROUGHING IS FORECAST TO BUILD OVER THE EASTERN CONUS DURING THE 8-14
DAY PERIOD, RESULTING IN A TILT TOWARDS ABOVE-NORMAL PRECIPITATION OVER MOST OF
THE EASTERN CONUS AND PARTS OF THE SOUTHERN PLAINS. ABOVE-NORMAL PRECIPITATION
IS FAVORED OVER PARTS OF CALIFORNIA AND NEVADA, WHILE BELOW-NORMAL
PRECIPITATION IS LIKELY OVER THE PACIFIC NORTHWEST, THE NORTHERN GREAT BASIN,
THE NORTHERN ROCKIES, AND PORTIONS OF THE NORTHERN AND CENTRAL PLAINS, AND THE
UPPER AND MIDDLE MISSISSIPPI VALLEY, CONSISTENT WITH THE GEFS AND ECMWF
PRECIPITATION REFORECAST TOOLS. CONTINUED SURFACE LOW PRESSURE OVER THE
ALEUTIANS IS FAVORED BY MODEL GUIDANCE, RESULTING IN ELEVATED PROBABILITIES FOR
NEAR- TO ABOVE-NORMAL PRECIPITATION FOR MUCH OF ALASKA.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 40% OF TODAY'S GFS
SUPERENSEMBLE MEAN CENTERED ON DAY 11, 30% 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
MODEL AGREEMENT ON AN AMPLIFIED 500-HPA PATTERN ACROSS MUCH OF THE FORECAST
DOMAIN.
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
APRIL 20.
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:
19520401 - 19620430 - 19610418 - 19790413 - 19860415
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:
19520331 - 19610418 - 19790412 - 19620501 - 20010415
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 25 - 29 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A B
SRN CALIF A B IDAHO A B NEVADA A B
W MONTANA N B E MONTANA B N WYOMING B N
UTAH A B ARIZONA A N COLORADO N A
NEW MEXICO N N N DAKOTA B A S DAKOTA B A
NEBRASKA B A KANSAS B A OKLAHOMA B A
N TEXAS B A S TEXAS N A W TEXAS B N
MINNESOTA B A IOWA B A MISSOURI B A
ARKANSAS B A LOUISIANA B A WISCONSIN B A
ILLINOIS B A MISSISSIPPI B A MICHIGAN B A
INDIANA B A OHIO B A KENTUCKY B A
TENNESSEE B A ALABAMA B A NEW YORK N A
VERMONT N A NEW HAMP N A MAINE N N
MASS N A CONN N A RHODE IS N A
PENN B A NEW JERSEY N A W VIRGINIA B A
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL A A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN B N AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL N A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 27 - MAY 03, 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON A N NRN CALIF A A
SRN CALIF N A IDAHO A N NEVADA A A
W MONTANA B N E MONTANA B N WYOMING B N
UTAH A N ARIZONA A N COLORADO B N
NEW MEXICO N N N DAKOTA B N S DAKOTA B N
NEBRASKA B N KANSAS B N OKLAHOMA B N
N TEXAS B N S TEXAS B N W TEXAS B N
MINNESOTA B N IOWA B N MISSOURI B N
ARKANSAS B N LOUISIANA B N WISCONSIN B N
ILLINOIS B N MISSISSIPPI B N MICHIGAN B N
INDIANA B N OHIO B N KENTUCKY B N
TENNESSEE B N ALABAMA B N NEW YORK B N
VERMONT B N NEW HAMP B N MAINE N N
MASS B N CONN B N RHODE IS B N
PENN B N NEW JERSEY B N W VIRGINIA B N
MARYLAND B N DELAWARE B N VIRGINIA B N
N CAROLINA B N S CAROLINA B N GEORGIA B N
FL PNHDL B N FL PENIN A N AK N SLOPE B A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL A 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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page