148
FXUS06 KWBC 291903
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MAY 29 2023
6-10 DAY OUTLOOK FOR JUN 04 - 08 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 ACROSS THE ALEUTIANS. A TROUGH
AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES CONTINUES TO BE PREDICTED OVER
SOUTHERN CALIFORNIA. AN AMPLIFIED RIDGE AND ASSOCIATED POSITIVE 500-HPA HEIGHT
ANOMALIES ARE PREDICTED TO PERSIST FROM ABOUT THE CENTRAL GREAT PLAINS
NORTHWARD AND NORTHWESTWARD ACROSS CENTRAL AND WESTERN CANADA, AND ACROSS
NORTHERN ALASKA. ALL ENSEMBLE MEANS PREDICT A WEAK TROUGH OVER THE GULF OF
MEXICO/SOUTHEAST DURING THE 6-10 DAY PERIOD.
BELOW NORMAL TEMPERATURES ARE FAVORED FOR ALEUTIANS AND SOUTHWESTERN ALASKA
DURING THE 6-10 DAY PERIOD, WHILE ABOVE NORMAL TEMPERATURES ARE FAVORED FOR
NORTHERN MAINLAND ALASKA, CONSISTENT WITH THE CONSOLIDATION OF CALIBRATED
DYNAMICAL MODEL TEMPERATURE FORECASTS. ABOVE NORMAL TEMPERATURES ARE VERY
LIKELY ACROSS MOST OF THE NORTHERN CONTIGUOUS U.S. (CONUS) UNDER THE PREDICTED
AMPLIFIED RIDGE AND POSITIVE 500-HPA HEIGHT ANOMALIES. THIS AREA OF FAVORED
ABOVE NORMAL TEMPERATURES IS EXPECTED TO EXTEND SOUTHWARD ACROSS THE TENNESSEE
AND LOWER MISSISSIPPI VALLEYS DUE TO THE BRIEF INTERACTION WITH A WEAK
MID-LEVEL RIDGE FORECAST NEAR THAT AREA. PROBABILITIES FAVORING ABOVE NORMAL
TEMPERATURES ACROSS THE NORTHERN CONUS EXCEED 80 PERCENT OVER PORTIONS OF THE
PACIFIC NORTHWEST AND THE NORTHERN GREAT BASIN. BELOW NORMAL TEMPERATURES ARE
FAVORED FROM SOUTHERN CALIFORNIA EASTWARD THROUGH MUCH OF THE SOUTHWEST INTO
THE CENTRAL AND SOUTHERN PLAINS, ASSOCIATED WITH A MID-LEVEL TROUGH AND BELOW
NORMAL 500-HPA HEIGHTS. BELOW NORMAL TEMPERATURES ARE ALSO FAVORED OVER MOST OF
THE ATLANTIC COAST, CONSISTENT WITH BIAS-CORRECTED AND CALIBRATED REFORECAST
TEMPERATURE TOOLS.
ABOVE NORMAL PRECIPITATION IS FAVORED OVER MOST OF THE WESTERN HALF OF THE
CONUS (EXCEPT FOR WESTERN WASHINGTON WHERE BELOW NORMAL PRECIPITATION IS
INDICATED), THE LOWER MISSISSIPPI VALLEY, AND PARTS OF GEORGIA AND FLORIDA.
THIS IS ASSOCIATED WITH THE UPSTREAM MID-LEVEL TROUGH NEAR THE WEST COAST, AND
MOISTURE FROM GULF OF MEXICO. PROBABILITIES FAVORING ABOVE NORMAL PRECIPITATION
EXCEED 60 PERCENT FOR PORTIONS OF CALIFORNIA, THE CENTRAL BASIN, AND INTO THE
FOUR CORNERS REGION. ENHANCED ODDS OF BELOW NORMAL PRECIPITATION ARE INDICATED
OVER UPPER AND MIDDLE PORTIONS OF THE MISSISSIPPI VALLEY, THE GREAT LAKES
REGION, OHIO VALLEY, CENTRAL AND NORTHERN APPALACHIANS, THE MID-ATLANTIC AND
PORTIONS OF THE NORTHEAST. THIS IS BASED ON INCREASED SUBSIDENCE OF AIR BETWEEN
AN UPSTREAM RIDGE OVER THE HIGH PLAINS AND A DOWNSTREAM TROUGH OVER THE
NORTHEAST CONUS AND CANADIAN MARITIMES. A SURFACE LOW PRESSURE SYSTEM AND A
500-HPA TROUGH OVER THE ALEUTIANS ARE FAVORED BY MODEL GUIDANCE, RESULTING IN
ELEVATED PROBABILITIES FOR ABOVE NORMAL PRECIPITATION FOR MUCH OF 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
GOOD MODEL AGREEMENT REGARDING THE 500-HPA HEIGHT FORECASTS ACROSS NORTH
AMERICA, OFFSET BY SMALL DIFFERENCES AMONG THE SURFACE TEMPERATURE AND
PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR JUN 06 - 12 2023
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A FAIRLY PERSISTENT
500-HPA CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS. A
TROUGH IS FORECAST FROM THE ALEUTIANS SOUTHEASTWARD ACROSS THE GULF OF ALASKA
AND WEST COAST OF THE CONUS, A RIDGE IS DEPICTED FROM THE WESTERN CONUS
NORTHWESTWARD ACROSS WESTERN CANADA AND NORTHERN ALASKA, AND A TROUGH IS
PREDICTED OVER EASTERN NORTH AMERICA. THE MANUAL 500-HPA HEIGHT BLEND FORECASTS
POSITIVE HEIGHT ANOMALIES OVER NORTHERN AND ALASKA, AND NORTHWESTERN PORTIONS
OF THE LOWER 48 STATES. NEGATIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED OVER
MOST OF THE REMAINDER OF THE CONUS.
BELOW NORMAL TEMPERATURES ARE FAVORED OVER MOST OF THE SOUTHWESTERN,
SOUTH-CENTRAL, AND EASTERN CONUS ASSOCIATED WITH MID-LEVEL TROUGHS AND
ACCOMPANYING NEGATIVE 500-HPA HEIGHT DEPARTURES. BELOW NORMAL TEMPERATURES ARE
ALSO INDICATED OVER SOUTHWESTERN PORTIONS OF ALASKA IN PROXIMITY TO A MID-LEVEL
TROUGH. MID-LEVEL RIDGING AND ASSOCIATED POSITIVE HEIGHT ANOMALIES TILT THE
ODDS TOWARDS ABOVE NORMAL TEMPERATURES FOR NORTHERN, AND SOUTHEAST ALASKA, AND
THE NORTHERN CONUS FROM THE PACIFIC NORTHWEST AND NORTHERN INTERMOUNTAIN REGION
EASTWARD ACROSS THE NORTHERN PLAINS, AND INTO THE UPPER MISSISSIPPI VALLEY.
PROBABILITIES FOR ABOVE NORMAL TEMPERATURES EXCEED 70 PERCENT OVER PORTIONS OF
THE PACIFIC NORTHWEST AND THE NORTHERN GREAT BASIN. ABOVE NORMAL TEMPERATURES
ARE ALSO FAVORED OVER THE GULF COAST AS SUPPORTED BY THE CONSOLIDATION
PRECIPITATION TOOL.
ABOVE NORMAL PRECIPITATION CONTINUES TO BE FAVORED OVER MOST OF THE WESTERN
HALF OF THE CONUS, CONTINUING EASTWARD OVER THE LOWER MISSISSIPPI AND TENNESSEE
VALLEYS, AND THE SOUTHEAST. THIS IS CONSISTENT WITH THE CONSOLIDATION OF
CALIBRATED MODEL PRECIPITATION FORECASTS. BELOW NORMAL PRECIPITATION IS FAVORED
FOR THE UPPER MISSISSIPPI VALLEY, EAST OF THE MID-LEVEL RIDGE PREDICTED TO BE
CENTERED OVER THE NORTHWESTERN CONUS. ABOVE NORMAL PRECIPITATION IS LIKELY OVER
PARTS OF THE NORTHEAST, AND MOST OF ALASKA IN WEEK 2, SUPPORTED BY MOST
DYNAMICAL PRECIPITATION FORECAST TOOLS. THERE ARE ELEVATED ODDS OF BELOW NORMAL
PRECIPITATION FOR FAR SOUTHEAST ALASKA ASSOCIATED WITH RISING 500-HPA HEIGHTS
AND INCREASED RIDGING.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S GFS
SUPERENSEMBLE 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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT ON THE 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
JUNE 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:
19910606 - 19890516 - 19560604 - 19620605 - 19980509
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:
19910607 - 19560602 - 19890516 - 19920508 - 19780526
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 04 - 08 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A A NRN CALIF A A
SRN CALIF B A IDAHO A A NEVADA A A
W MONTANA A A E MONTANA A A WYOMING A A
UTAH A 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 B A
N TEXAS B A S TEXAS B A W TEXAS B A
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS A A LOUISIANA N A WISCONSIN A B
ILLINOIS A B MISSISSIPPI A A MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY A B
TENNESSEE A N ALABAMA N N NEW YORK A B
VERMONT N B NEW HAMP N B MAINE N N
MASS B N CONN B B RHODE IS B N
PENN A B NEW JERSEY B B W VIRGINIA N B
MARYLAND B B DELAWARE B B VIRGINIA B B
N CAROLINA B N S CAROLINA B N GEORGIA B N
FL PNHDL B N FL PENIN B N AK N SLOPE A N
AK ALEUTIAN B A AK WESTERN N A AK INT BSN A A
AK S INT B A AK SO COAST B A AK PNHDL A A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 06 - 12 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF B A IDAHO A A NEVADA A A
W MONTANA A A E MONTANA A A WYOMING N A
UTAH B A ARIZONA B N COLORADO B A
NEW MEXICO B A N DAKOTA A N S DAKOTA N N
NEBRASKA B A KANSAS B A OKLAHOMA B A
N TEXAS B A S TEXAS A A W TEXAS B A
MINNESOTA N N IOWA N N MISSOURI B N
ARKANSAS B A LOUISIANA A A WISCONSIN N N
ILLINOIS B N MISSISSIPPI N N MICHIGAN N N
INDIANA B N OHIO B N KENTUCKY B N
TENNESSEE B A ALABAMA N N NEW YORK N N
VERMONT B N NEW HAMP B N MAINE B N
MASS N N CONN N N RHODE IS N N
PENN N N NEW JERSEY B N W VIRGINIA B N
MARYLAND B N DELAWARE B N VIRGINIA B N
N CAROLINA B N S CAROLINA N N GEORGIA N N
FL PNHDL A N FL PENIN A N AK N SLOPE A A
AK ALEUTIAN B A AK WESTERN N A AK INT BSN N A
AK S INT N 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.
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