905
FXUS06 KWBC 272007
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE FEBRUARY 27 2024
6-10 DAY OUTLOOK FOR MAR 04 - 08 2024
TODAY’S ENSEMBLE MEAN FORECASTS FROM THE GEFS, ECMWF AND CANADIAN MODELS ARE IN
AGREEMENT IN PREDICTING AN AMPLIFIED MID-LEVEL CIRCULATION PATTERN OVER THE
FORECAST DOMAIN DURING THE 6-10 DAY PERIOD. HOWEVER THERE IS SIGNIFICANT
EVOLUTION OF THE CIRCULATION PATTERN FROM YESTERDAY’S FORECASTS AND INCREASING
DIFFERENCES AMONG MODEL SOLUTIONS. ALL MODELS PREDICT A POSITIVE 500-HPA HEIGHT
ANOMALY OVER THE NORTHWESTERN PACIFIC AND PARTS OF THE ALEUTIAN ISLANDS. THE
ECMWF PREDICTS AN AMPLIFIED RIDGE AND POSITIVE 500-HPA HEIGHT ANOMALIES OVER
MAINLAND ALASKA, WHILE THE GEFS PREDICTS A TROUGH AND NEGATIVE ANOMALIES OVER
THE MAINLAND. MID-LEVEL FLOW IS SOUTHWESTERLY INTO SOUTHEAST ALASKA IN THE GEFS
ENSEMBLE MEAN SOLUTION, AND NORTHWESTERLY IN THE ECMWF. A TROUGH EXTENDS FROM
CANADA INTO THE WESTERN AND CENTRAL CONUS IN ENSEMBLE MEAN MODEL FORECASTS,
WITH VARIATIONS IN THE ORIENTATION OF THIS TROUGH AMONG MODELS. THE ECMWF
PREDICTS A BROAD TROUGH OVER THE PACIFIC AND WESTERN CONUS WITH RELATIVELY
ZONAL FLOW INTO THE PACIFIC COAST, WHILE THE GEFS PREDICTS A POSITIVE TILT IN
THE TROUGH FROM THE SOUTHWEST TO THE NORTHERN PLAINS. AN AMPLIFIED POSITIVE
500-HPA HEIGHT ANOMALY IS PREDICTED OVER EASTERN NORTH AMERICA, CENTERED NEAR
NEWFOUNDLAND, IN ALL ENSEMBLE MEANS AND THE MANUAL BLEND OF 500-HPA HEIGHT
FORECASTS.
BELOW NORMAL TEMPERATURES ARE FAVORED FOR SOUTHERN AND EASTERN MAINLAND ALASKA
AND LIKELY FOR THE SOUTHERN ALASKA PANHANDLE, UNDER PREDICTED NEGATIVE 500-HPA
ANOMALIES IN MOST MODEL FORECASTS. NEAR NORMAL IS FAVORED OVER AREAS OF WESTERN
MAINLAND ALASKA AND THE ALEUTIANS, WHERE THERE IS GREATER UNCERTAINTY DUE TO
DIFFERENCES IN MODEL TOOLS. BELOW NORMAL TEMPERATURES ARE LIKELY FOR MOST OF
THE WESTERN CONUS, UNDER THE PREDICTED TROUGH. PROBABILITIES FOR BELOW NORMAL
TEMPERATURES EXCEED 70 PERCENT FOR MUCH OF EASTERN CALIFORNIA AND WESTERN
NEVADA. ABOVE NORMAL TEMPERATURES ARE LIKELY FROM GENERALLY THE EASTERN GREAT
PLAINS TO THE ATLANTIC. PROBABILITIES FOR ABOVE NORMAL TEMPERATURES EXCEED 90
PERCENT FOR MUCH OF THE EASTERN GREAT LAKES REGION AND NORTHEAST. NEAR NORMAL
TEMPERATURES ARE FAVORED FOR HAWAII, CONSISTENT WITH AUTOMATED AND
CONSOLIDATION TEMPERATURE TOOLS.
THE PREDICTED CIRCULATION PATTERN OVER ALASKA FAVORS ABOVE NORMAL PRECIPITATION
FROM THE EASTERN ALEUTIANS ACROSS SOUTHERN MAINLAND ALASKA, WHILE BELOW NORMAL
PRECIPITATION IS SLIGHTLY FAVORED FOR THE NORTHWESTERN COAST OF MAINLAND
ALASKA. PREDICTED ONSHORE FLOW SLIGHTLY FAVORS ABOVE NORMAL PRECIPITATION FOR
THE PACIFIC COAST. ABOVE NORMAL PRECIPITATION IS FAVORED FROM SOUTHERN
CALIFORNIA AND THE SOUTHWEST NORTHEASTWARD INTO THE GREAT PLAINS, AHEAD OF THE
PREDICTED TROUGH. ABOVE NORMAL PRECIPITATION IS MORE LIKELY FOR THE EASTERN
CONUS, AHEAD OF THE BROAD MID-LEVEL TROUGH AND WITH SOUTHERLY SURFACE FLOW.
PROBABILITIES FOR ABOVE NORMAL PRECIPITATION EXCEED 60 PERCENT FOR PARTS OF THE
SOUTHEAST. NEAR TO ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR HAWAII,
WITH PREDICTED CYCLONIC FLOW.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 40% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 20% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, WITH
GOOD OVERALL AGREEMENT ON THE PREDICTED 500-HPA HEIGHT PATTERN, OFFSET BY A
SIGNIFICANT INCREASE IN UNCERTAINTY AMONG MODEL FORECASTS AND SIGNIFICANT
DIFFERENCES AMONG TEMPERATURE AND PRECIPITATION TOOLS IN SOME REGIONS, SUCH AS
ALASKA.
8-14 DAY OUTLOOK FOR MAR 06 - 12 2024
DYNAMICAL MODELS CONTINUE TO BE IN FAIR AGREEMENT ON THE OVERALL PREDICTED
MID-LEVEL CIRCULATION PATTERN DURING THE 8-14 DAY PERIOD, SHOWING SOME
EVOLUTION OF THE MEAN PATTERN FROM THE 6-10 DAY PERIOD. A POSITIVE 500-HPA
HEIGHT ANOMALY PERSISTS OVER THE NORTH PACIFIC AND ALEUTIANS DURING THE 8-14
DAY PERIOD. NEGATIVE 500-HPA HEIGHT ANOMALIES CONTINUE OVER MUCH OF MAINLAND
ALASKA INTO WEEK 2 IN THE ENSEMBLE MEAN FORECASTS. A PREDICTED TROUGH OVER THE
WESTERN CONUS DEAMPLIFIES SOMEWHAT IN THE WEEK 2 PERIOD RELATIVE TO THE 6-10
DAY PERIOD. NEGATIVE 500-HPA HEIGHT ANOMALIES EXTEND EASTWARD INTO THE CENTRAL
AND LOWER MISSISSIPPI VALLEY IN WEEK 2. A POSITIVE 500-HPA HEIGHT ANOMALY OVER
THE NORTHEASTERN CONUS AT THE START OF WEEK 2, PROGRESSES EASTWARD DURING THE
PERIOD IN ENSEMBLE MEAN SOLUTIONS.
BELOW NORMAL TEMPERATURES ARE FAVORED OVER MAINLAND ALASKA IN WEEK 2, UNDER
PRIMARILY NEGATIVE 500-HPA HEIGHT ANOMALIES, WHILE NEAR NORMAL TEMPERATURES ARE
FAVORED FOR THE ALEUTIANS AND SOUTHEAST ALASKA. BELOW NORMAL TEMPERATURES ARE
FAVORED IN WEEK 2 OVER MUCH OF THE WEST FROM THE PACIFIC COAST TO THE ROCKY
MOUNTAINS, ON THE WESTERN SIDE OF A PREDICTED TROUGH. ABOVE NORMAL TEMPERATURES
ARE MOST LIKELY FURTHER EAST OVER THE CONUS, FROM PARTS OF THE NORTHERN PLAINS,
CENTRAL PLAINS, AND LOWER MISSISSIPPI VALLEY TO THE ATLANTIC COAST, UNDER
POSITIVE 500-HPA HEIGHT ANOMALIES AT THE START OF THE PERIOD. PROBABILITIES FOR
ABOVE NORMAL TEMPERATURES EXCEED 80 PERCENT FOR THE NORTHEAST, WHILE
PROBABILITIES ARE MORE MODEST OVER THE SOUTHEAST, WHERE 500-HPA HEIGHT
ANOMALIES ARE PREDICTED TO DROP TO NEAR ZERO DURING THE PERIOD. NEAR NORMAL
TEMPERATURES ARE FAVORED FOR HAWAII, CONSISTENT WITH THE AUTOMATED TEMPERATURE
BLEND AND THE CONSOLIDATION.
ABOVE NORMAL PRECIPITATION IS FAVORED FOR THE EASTERN ALEUTIANS, EASTERN
MAINLAND ALASKA, AND SOUTHEAST ALASKA, CONSISTENT WITH MOST DYNAMICAL MODEL
PRECIPITATION TOOLS. BELOW NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR THE
NORTHWESTERN COAST OF MAINLAND ALASKA, CONSISTENT WITH THE PRECIPITATION
CONSOLIDATION. ABOVE NORMAL PRECIPITATION CONTINUES TO BE FAVORED OVER THE
WESTERN CONUS, AHEAD OF ONSHORE FLOW. ABOVE NORMAL PRECIPITATION IS FAVORED
FROM THE SOUTHWESTERN CONUS ACROSS MOST OF THE CENTRAL AND SOUTHERN PLAINS,
AHEAD OF THE PREDICTED TROUGH. BELOW NORMAL PRECIPITATION IS FAVORED OVER PARTS
OF THE NORTHERN PLAINS, SUPPORTED BY REFORECAST-CALIBRATED PRECIPITATION
FORECASTS FROM THE GEFS AND ECMWF. ABOVE NORMAL PRECIPITATION IS FAVORED FOR
THE EASTERN CONUS, SUPPORTED BY REFORECAST-CALIBRATED ECMWF PRECIPITATION
FORECASTS. NEAR NORMAL PRECIPITATION IS FAVORED FOR MOST OF THE HAWAIIAN
ISLANDS IN WEEK 2, WHILE BELOW NORMAL PRECIPITATION IS FAVORED FOR KAUAI.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 40% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 20% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, WITH
GOOD AGREEMENT ON THE OVERALL PREDICTED 500-HPA HEIGHT PATTERN, OFFSET BY
UNCERTAINTIES ASSOCIATED WITH THE DEAMPLIFICATION AND PROGRESSION OF THE
PREDICTED MID-LEVEL HEIGHT ANOMALIES, AS WELL AS DIFFERENCES AMONG 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
MARCH 21.
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:
19550309 - 19820310 - 19900211 - 20060221 - 19570208
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:
19550310 - 19570208 - 19820309 - 19900211 - 19850303
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 04 - 08 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO B N NEVADA B A
W MONTANA B N E MONTANA B N WYOMING B A
UTAH B A ARIZONA B A COLORADO B A
NEW MEXICO B A N DAKOTA N A S DAKOTA N A
NEBRASKA A A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA A A IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A A
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK A A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN A A RHODE IS A A
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A A 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 N N
AK ALEUTIAN N A AK WESTERN N B AK INT BSN B N
AK S INT B A AK SO COAST B A AK PNHDL N N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 06 - 12 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO B A NEVADA B A
W MONTANA N N E MONTANA N B WYOMING N N
UTAH B A ARIZONA B A COLORADO N A
NEW MEXICO B A N DAKOTA A B S DAKOTA A N
NEBRASKA A A KANSAS N A OKLAHOMA N A
N TEXAS N A S TEXAS N A W TEXAS N A
MINNESOTA A N IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A N
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK A A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN A A RHODE IS A A
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A A 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 B N AK WESTERN B N AK INT BSN B A
AK S INT B A AK SO COAST B 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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