473
FXUS06 KWBC 261902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI MAY 26 2023
6-10 DAY OUTLOOK FOR JUN 01 - 05 2023
DYNAMICAL MODEL ENSEMBLE MEAN FORECASTS ARE IN GOOD AGREEMENT ON THE PREDICTED
500-HPA CIRCULATION PATTERN OVER THE NORTH AMERICAN DOMAIN DURING THE 6-10 DAY
PERIOD. THE AMPLIFIED RIDGE PREDICTED YESTERDAY ACROSS THE ALEUTIANS AND BERING
SEA HAS RAPIDLY DE-AMPLIFIED IN TODAY’S RUNS. THIS ABRUPT CHANGE MAY BE RELATED
TO HOW THE VARIOUS DYNAMICAL MODELS HANDLE THE EXPECTED RECURVATURE OF TYPHOON
MAWAR WHICH RECENTLY SWEPT THROUGH GUAM AND NEARBY NORTHERN MARIANA ISLANDS IN
THE WESTERN PACIFIC. THE ENSEMBLE MEAN SOLUTIONS AGREE ON MID-LEVEL TROUGHING
THAT EXTENDS FROM THE GULF OF ALASKA SOUTHEASTWARD TO THE VICINITY OF
CALIFORNIA, AND CONTINUING EASTWARD INTO THE SOUTHERN ROCKIES. AN AMPLIFIED
RIDGE IS PREDICTED TO PERSIST FROM ABOUT THE CENTRAL GREAT PLAINS NORTHWARD AND
NORTHWESTWARD ACROSS CENTRAL AND WESTERN CANADA. THE 0Z GEFS EXTENDS THIS RIDGE
ACROSS ALASKA. A MID-LEVEL TROUGH IS ANTICIPATED OVER THE CANADIAN MARITIMES,
WITH THE WESTERN PORTIONS OF THE TROUGH AS FAR WEST AS THE NORTHEAST CONUS. ALL
ENSEMBLE MEANS PREDICT A WEAK TROUGH OVER THE FAR EASTERN GULF OF
MEXICO/FLORIDA DURING THE 6-10 DAY PERIOD. TODAY’S MANUAL HEIGHT BLEND SHOWS
GOOD CONTINUITY WITH YESTERDAY’S MANUAL HEIGHT BLEND, EXCEPT FOR THE FAR
NORTHERN PACIFIC/BERING SEA REGION, WHERE MID-TROPOSPHERIC HEIGHTS ARE FORECAST
TO COLLAPSE RAPIDLY.
BELOW NORMAL TEMPERATURES ARE FAVORED FOR SOUTHWESTERN ALASKA DURING THE 6-10
DAY PERIOD, WHILE ABOVE NORMAL TEMPERATURES ARE FAVORED FOR NORTHERN AND
PORTIONS OF SOUTHEAST ALASKA, CONSISTENT WITH THE CONSOLIDATION OF CALIBRATED
DYNAMICAL MODEL TEMPERATURE FORECASTS. ABOVE NORMAL TEMPERATURES ARE VERY
LIKELY ACROSS THE NORTHERN CONUS UNDER THE PREDICTED AMPLIFIED RIDGE AND
POSITIVE 500-HPA HEIGHT ANOMALIES. PROBABILITIES FAVORING ABOVE NORMAL
TEMPERATURES ACROSS THE NORTHERN CONUS EXCEED 80 PERCENT OVER PORTIONS OF THE
NORTH-CENTRAL CONUS. BELOW NORMAL TEMPERATURES ARE FAVORED FROM MOST OF
CALIFORNIA EASTWARD THROUGH MUCH OF THE SOUTHWEST INTO THE SOUTHERN PLAINS,
ASSOCIATED WITH A MID-LEVEL TROUGH AND BELOW NORMAL 500-HPA HEIGHTS. BELOW
NORMAL TEMPERATURES ARE ALSO FAVORED OVER MOST OF THE SOUTH ATLANTIC REGION,
CONSISTENT WITH BIAS-CORRECTED AND CALIBRATED REFORECAST TEMPERATURE TOOLS.
ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS WESTERN AND NORTHERN PORTIONS OF
ALASKA, WHILE BELOW NORMAL PRECIPITATION IS FAVORED FOR PARTS OF SOUTHEAST
ALASKA, CONSISTENT WITH THE PRECIPITATION CONSOLIDATION OF CALIBRATED MODEL
PRECIPITATION FORECASTS. WIDESPREAD ABOVE NORMAL PRECIPITATION IS FAVORED FROM
MOST OF THE WESTERN HALF OF THE CONUS EASTWARD OVER THE LOWER MISSISSIPPI AND
TENNESSEE VALLEYS, AND THE SOUTHEAST. THIS IS ASSOCIATED WITH THE UPSTREAM
MID-LEVEL TROUGH NEAR THE WEST COAST, AND MODEST GULF INFLOW FROM ABOUT THE
LOWER MISSISSIPPI VALLEY EASTWARD TO THE SOUTHEAST COAST. PROBABILITIES
FAVORING ABOVE NORMAL PRECIPITATION EXCEED 60 PERCENT FOR PORTIONS OF
CALIFORNIA, THE CENTRAL BASIN, AND INTO THE FOUR CORNERS REGION. THE AREA JUST
EAST OF FLORIDA WILL NEED TO BE MONITORED FOR POSSIBLE DEVELOPMENT OF A
TROPICAL CYCLONE, AND HAS SOME SUPPORT FROM CLIMATOLOGY. 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 PLAINS AND A
DOWNSTREAM TROUGH OVER THE NORTHEAST CONUS AND CANADIAN MARITIMES. NORTHERLY
SURFACE FLOW FAVORS BELOW NORMAL PRECIPITATION FOR PORTIONS OF THE PACIFIC
NORTHWEST.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 ON A SCALE OF
1-5, FOR THE CONUS DUE TO WELL SPECIFIED MID-LEVEL LONG-WAVE FEATURES, BUT
OFFSET BY THE UNCERTAINTY ACROSS THE ALASKA DOMAIN ASSOCIATED WITH THE
PREDICTED RAPID COLLAPSE OF THE MID-LEVEL RIDGE OVER THE ALEUTIANS/BERING SEA
AREA.
8-14 DAY OUTLOOK FOR JUN 03 - 09 2023
DESPITE THE PREDICTED RAPID UPSTREAM CHANGES IN THE 500-HPA CIRCULATION PATTERN
DURING THE 6-10 DAY PERIOD, THE NORTH AMERICAN CIRCULATION RAPIDLY CONSOLIDATES
INTO THREE MAJOR LONG-WAVES, WITH PHASING OF NORTHERN AND SOUTHERN STREAM
FEATURES. ACCORDING TO THE 0Z ENSEMBLE MEAN SOLUTIONS, A TROUGH IS FORECAST
FROM THE BERING SEA SOUTHEASTWARD ACROSS THE GULF OF ALASKA AND WEST COAST OF
THE CONUS, A RIDGE IS DEPICTED FROM THE CENTRAL 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 MOST OF ALASKA AND CANADA, AND NORTHWESTERN AND NORTH-CENTRAL
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 SOUTHERN CONUS AND MOST
OF THE EASTERN QUARTER OF THE CONUS, ASSOCIATED WITH MID-LEVEL TROUGHS AND
ACCOMPANYING NEGATIVE 500-HPA HEIGHT DEPARTURES. HOWEVER, LINGERING POSITIVE
500-HPA HEIGHT ANOMALIES ARE FORECAST FOR THE NORTHEAST CONUS, ASSOCIATED WITH
THE RETROGRADING UPSTREAM MID-LEVEL RIDGE. PROBABILITIES FOR BELOW NORMAL
TEMPERATURES EXCEED 60 PERCENT OVER PORTIONS OF THE SOUTHERN ROCKIES AND
SOUTHERN HIGH PLAINS. 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, EASTERN, 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 THE NORTHERN
INTERMOUNTAIN REGION. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED OVER CENTRAL
AND SOUTHERN FLORIDA, IN THE RELATIVELY WARM SUBTROPICAL FLOW JUST AHEAD OF A
MID-LEVEL TROUGH AXIS.
ABOVE NORMAL PRECIPITATION IS FAVORED FOR WESTERN PORTIONS OF ALASKA IN WEEK 2,
SUPPORTED BY DYNAMICAL MODEL PRECIPITATION TOOLS AND CALIBRATED REFORECAST
PRECIPITATION TOOLS. THERE ARE ELEVATED ODDS OF BELOW NORMAL PRECIPITATION FOR
SOUTHEASTERN PORTIONS OF THE ALASKA MAINLAND AND SOUTHEAST ALASKA ASSOCIATED
WITH RISING 500-HPA HEIGHTS AND INCREASED RIDGING. 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. ABOVE NORMAL PRECIPITATION IS ALSO FAVORED OVER PORTIONS OF NEW
ENGLAND, JUST AHEAD OF A MEAN TROUGH AXIS. BELOW NORMAL PRECIPITATION IS
FAVORED FOR THE UPPER AND MIDDLE MISSISSIPPI VALLEY, GREAT LAKES REGION, OHIO
VALLEY, AND CENTRAL AND NORTHERN APPALACHIANS, EAST OF THE MID-LEVEL RIDGE
PREDICTED TO BE CENTERED OVER THE HIGH PLAINS. THIS MID-LEVEL CIRCULATION
PATTERN CONTINUES TO FAVOR BELOW-NORMAL PRECIPITATION FOR THE CENTRAL AND
EASTERN CORN BELT. RAINFALL DEFICITS RANGE FROM 1-3 INCHES BELOW NORMAL FOR
THIS AREA DURING THE PAST 30-60 DAYS, AND SOIL MOISTURE IS CURRENTLY BELOW THE
30TH CLIMATOLOGICAL PERCENTILE. THIS REGION IS BEING MONITORED FOR THE
POSSIBILITY OF RAPID-ONSET DROUGHT.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: NEAR AVERAGE, 3 ON A SCALE OF 1-5,
DUE TO GENERAL AGREEMENT ON THE MEAN LARGE-SCALE CIRCULATION PATTERN OVER THE
CONUS, OFFSET BY UNCERTAINTIES IN THE UPSTREAM CIRCULATION OVER THE VICINITY OF
ALASKA AND THE ADJACENT NORTH PACIFIC.
FORECASTER: ANTHONY A
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:
20020609 - 19910519 - 19780530 - 19910606 - 19720527
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:
19780531 - 19720526 - 20070507 - 19910607 - 19910518
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 01 - 05 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF B A
SRN CALIF B A IDAHO A A NEVADA N A
W MONTANA A A E MONTANA A A WYOMING A A
UTAH N A ARIZONA B A COLORADO B A
NEW MEXICO B A N DAKOTA A N S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA N A
N TEXAS B A S TEXAS B A W TEXAS B A
MINNESOTA A B IOWA A B MISSOURI A N
ARKANSAS A A LOUISIANA N A WISCONSIN A B
ILLINOIS A B MISSISSIPPI N A MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY A B
TENNESSEE A N ALABAMA N A NEW YORK A B
VERMONT A B NEW HAMP A N MAINE A N
MASS A N CONN A B RHODE IS A N
PENN A B NEW JERSEY A B W VIRGINIA A B
MARYLAND A B DELAWARE A B VIRGINIA A B
N CAROLINA N N S CAROLINA B N GEORGIA B A
FL PNHDL B A FL PENIN N A AK N SLOPE N A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN N N
AK S INT B N AK SO COAST B N AK PNHDL N B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 03 - 09 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF B A
SRN CALIF B A IDAHO A A NEVADA N A
W MONTANA A A E MONTANA A A WYOMING A A
UTAH N A ARIZONA B N COLORADO B A
NEW MEXICO B A N DAKOTA A N S DAKOTA A N
NEBRASKA N N KANSAS B 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 B A LOUISIANA B A WISCONSIN A B
ILLINOIS N B MISSISSIPPI B A MICHIGAN N B
INDIANA N B OHIO N B KENTUCKY N N
TENNESSEE B N ALABAMA B A NEW YORK B N
VERMONT B N NEW HAMP B N MAINE B N
MASS B N CONN B N RHODE IS N N
PENN N B NEW JERSEY N N W VIRGINIA N N
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA B N S CAROLINA B A GEORGIA B A
FL PNHDL N A FL PENIN A A AK N SLOPE A A
AK ALEUTIAN B A AK WESTERN N A AK INT BSN A N
AK S INT N N AK SO COAST N N 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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