300
FXUS06 KWBC 221940
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 22 2023
6-10 DAY OUTLOOK FOR MAY 28 - JUN 01, 2023
DYNAMICAL MODEL ENSEMBLE MEAN FORECASTS ARE IN GOOD AGREEMENT ON THE PREDICTED
500-HPA CIRCULATION PATTERN OVER NORTH AMERICA DURING THE 6-10 DAY PERIOD.
GEFS, ECMWF AND CANADIAN ENSEMBLE MEAN SOLUTIONS PREDICT AN AMPLIFIED RIDGE AND
ASSOCIATED POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE ALEUTIAN ISLANDS DURING
THE 6-10 DAY PERIOD, WITH DOWNSTREAM TROUGHING AND WEAKER HEIGHT ANOMALIES OVER
THE GULF OF ALASKA. A TROUGH AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES
ARE PREDICTED OVER SOUTHERN CALIFORNIA AND ARE PREDICTED TO AMPLIFY SLIGHTLY
NEAR THE END OF THE PERIOD, ACCORDING TO ENSEMBLE MEAN FORECASTS. AN AMPLIFIED
RIDGE IS PREDICTED OVER CANADA AND THE NORTH-CENTRAL CONUS IN MODEL SOLUTIONS.
ALL ENSEMBLE MEANS PREDICT A SHORTWAVE TROUGH OVER THE SOUTHEAST DURING THE
6-10 DAY PERIOD.
BELOW NORMAL TEMPERATURES ARE LIKELY FOR MOST OF ALASKA DURING THE 6-10 DAY
PERIOD, UNDER NORTHERLY FLOW, WHILE NEAR TO ABOVE NORMAL TEMPERATURES ARE
FAVORED FOR NORTHERN ALASKA, CONSISTENT WITH MOST DYNAMICAL MODEL TEMPERATURE
TOOLS. ABOVE NORMAL TEMPERATURES ARE LIKELY ACROSS THE NORTHERN CONUS, UNDER
THE PREDICTED RIDGE AND POSITIVE 500-HPA HEIGHT ANOMALIES. ABOVE NORMAL
TEMPERATURES ARE SLIGHTLY FAVORED TO EXTEND SOUTHWARD ALONG THE MISSISSIPPI
VALLEY, SUPPORTED BY THE TEMPERATURE CONSOLIDATION OF CALIBRATED MODEL
FORECASTS. BELOW NORMAL TEMPERATURES ARE FAVORED FROM SOUTHERN CALIFORNIA
EASTWARD ALONG THE MEXICO-U.S. BORDER INTO SOUTH TEXAS, AHEAD OF THE PREDICTED
TROUGH AND SUPPORTED BY MOST DYNAMICAL MODEL TEMPERATURE TOOLS. BELOW NORMAL
TEMPERATURES ARE ALSO FAVORED FOR PARTS OF THE SOUTHEAST, UNDER PREDICTED
TROUGHING.
NEAR TO ABOVE NORMAL PRECIPITATION IS FAVORED FOR ALASKA, CONSISTENT WITH THE
PRECIPITATION CONSOLIDATION OF CALIBRATED MODEL PRECIPITATION FORECASTS, WITH
SLIGHTLY GREATER PROBABILITIES FOR THE EASTERN INTERIOR OF THE STATE.
WIDESPREAD ABOVE NORMAL PRECIPITATION IS FAVORED FOR THE INTERIOR WEST ACROSS
THE ROCKY MOUNTAINS INTO THE GREAT PLAINS, AHEAD OF THE PREDICTED TROUGH. DUE
TO UNCERTAINTY IN DYNAMICAL MODEL FORECASTS, NEAR NORMAL PRECIPITATION IS
FAVORED FOR FAR SOUTHERN CALIFORNIA AND ALONG THE CALIFORNIA COAST, WHERE ANY
POTENTIAL PRECIPITATION WOULD BE VERY LIGHT, DESPITE DYNAMICAL MODEL
PRECIPITATION TOOLS THAT PRIMARILY FAVOR ABOVE NORMAL PRECIPITATION IN THIS
AREA. BELOW NORMAL PRECIPITATION IS FAVORED FOR THE MIDWEST AND NORTHERN AREAS
OF THE NORTHEAST, UNDER AND AHEAD OF THE PREDICTED RIDGE. ABOVE NORMAL
PRECIPITATION IS FAVORED FOR PARTS OF THE CENTRAL ATLANTIC COAST, AHEAD OF A
PREDICTED SHORTWAVE TROUGH. BELOW NORMAL PRECIPITATION IS FAVORED FOR THE
WASHINGTON AND OREGON COASTS, SUPPORTED BY DYNAMICAL MODEL PRECIPITATION TOOLS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 0Z 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 ON A SCALE OF
1-5, DUE TO GENERAL AGREEMENT BETWEEN MODEL ENSEMBLE MEANS ON THE LARGE-SCALE
CIRCULATION PATTERN, OFFSET BY SMALL DIFFERENCES AMONG MODEL TEMPERATURE AND
PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR MAY 30 - JUN 05, 2023
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A SIMILAR LARGE-SCALE
CIRCULATION PATTERN TO THE 6-10 DAY PERIOD FORECASTS, WITH SOME EVOLUTION OF
THE PATTERN. AN AMPLIFIED RIDGE AND ASSOCIATED POSITIVE 500-HPA HEIGHT
ANOMALIES ARE PREDICTED OVER THE ALEUTIANS IN THE WEEK-2 PERIOD ALONG WITH
DOWNSTREAM TROUGHING OVER THE GULF OF ALASKA, WITH SOME EASTWARD PROGRESSION
RELATIVE TO THE 6-10 DAY PERIOD FORECASTS. THE PREDICTED TROUGH EXTENDS
SOUTHWARD DOWN THE PACIFIC COAST WITH GREATER AMPLITUDE NEGATIVE 500-HPA HEIGHT
ANOMALIES OVER SOUTHERN CALIFORNIA IN WEEK 2. A RIDGE AND ASSOCIATED POSITIVE
500-HPA HEIGHT ANOMALIES PERSIST OVER THE NORTHERN CONUS IN WEEK 2, WHILE
TROUGHING OVER THE SOUTHEAST DE-AMPLIFIES.
BELOW NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR MUCH OF ALASKA IN WEEK 2,
WHILE ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE NORTH SLOPE. ABOVE NORMAL
TEMPERATURES CONTINUE TO BE LIKELY ACROSS THE NORTHERN CONUS. ABOVE NORMAL
TEMPERATURES ARE SLIGHTLY FAVORED SOUTHWARD INTO THE MISSISSIPPI VALLEY AND
ALONG THE GULF COAST INTO FLORIDA, OVER A LARGER AREA THAN IN THE 6-10 DAY
PERIOD, SUPPORTED BY THE TEMPERATURE CONSOLIDATION. THE AREA OF ENHANCED
PROBABILITIES FOR BELOW NORMAL TEMPERATURES EXPANDS OVER THE SOUTHWESTERN CONUS
IN WEEK 2, UNDER AN AMPLIFYING TROUGH.
ABOVE NORMAL PRECIPITATION CONTINUES TO BE SLIGHTLY FAVORED FOR MUCH OF ALASKA
IN WEEK 2, SUPPORTED BY DYNAMICAL MODEL PRECIPITATION TOOLS. ALTHOUGH NEAR
NORMAL PRECIPITATION IS FAVORED FOR SOUTHEAST ALASKA, AS THE FLOW BECOMES MORE
WESTERLY, AND NEAR NORMAL IS FAVORED FOR NORTHERN ALASKA WITH INCREASING
UNCERTAINTY. BELOW NORMAL PRECIPITATION CONTINUES TO BE FAVORED FOR THE
WASHINGTON AND OREGON COASTS, SUPPORTED BY DYNAMICAL MODEL PRECIPITATION TOOLS.
ABOVE NORMAL PRECIPITATION CONTINUES TO BE FAVORED OVER A LARGE AREA OF THE
INTERIOR WEST AHEAD OF A TROUGH, SUPPORTED BY DYNAMICAL MODEL PRECIPITATION
TOOLS. PROBABILITIES OF ABOVE NORMAL PRECIPITATION ARE SLIGHTLY ENHANCED FOR
THE SOUTHEAST, CONSISTENT WITH THE CONSOLIDATION OF CALIBRATED MODEL
PRECIPITATION FORECASTS. BELOW NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR THE
MIDWEST, UNDER THE RIDGE.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 0Z 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 ON A SCALE OF
1-5, DUE TO GENERAL AGREEMENT ON THE MEAN LARGE-SCALE CIRCULATION PATTERN,
OFFSET BY INCREASING UNCERTAINTY AMONG MODEL TEMPERATURE AND PRECIPITATION
TOOLS.
FORECASTER: D COLLINS
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:
19810511 - 19510509 - 20070517 - 19920524 - 19780519
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:
19810510 - 20070517 - 19510512 - 19900502 - 19920523
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 28 - JUN 01, 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A A NRN CALIF N 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 N COLORADO N A
NEW MEXICO N A N DAKOTA A A S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA N A
N TEXAS N A S TEXAS B A W TEXAS N A
MINNESOTA A B IOWA A B MISSOURI A N
ARKANSAS A N LOUISIANA A N WISCONSIN A B
ILLINOIS A B MISSISSIPPI N N MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY N B
TENNESSEE B N ALABAMA B N NEW YORK A B
VERMONT A B NEW HAMP A B MAINE A B
MASS A N CONN A N RHODE IS A N
PENN A N NEW JERSEY N N W VIRGINIA N N
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA B A S CAROLINA B A GEORGIA B N
FL PNHDL B N FL PENIN A N AK N SLOPE N N
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 B A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 30 - JUN 05, 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON A A NRN CALIF N 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 N 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 A A WISCONSIN A B
ILLINOIS A B MISSISSIPPI A A MICHIGAN A B
INDIANA A B OHIO A B KENTUCKY A N
TENNESSEE A N ALABAMA A 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 N N VIRGINIA A N
N CAROLINA N A S CAROLINA N A GEORGIA N A
FL PNHDL N A FL PENIN A N AK N SLOPE A N
AK ALEUTIAN B N AK WESTERN B N AK INT BSN B N
AK S INT B N AK SO COAST B N AK PNHDL B 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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