784
FXUS06 KWBC 121924
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI APRIL 12 2024
6-10 DAY OUTLOOK FOR APR 18 - 22 2024
MODEL AGREEMENT HAS BEEN DEGRADING OVER THE LAST FEW DAYS AS A PREDICTED
AMPLIFIED 500-HPA CIRCULATION PATTERN IS DEPICTED BREAKING DOWN 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 GEFS, ECENS, AND
CANADIAN MODELS DUE TO RECENT MODEL SKILL. THE RESULTANT MANUAL BLEND FEATURES
POSITIVE 500-HPA HEIGHT ANOMALIES BUT CHAOTIC FLOW OVER ALASKA AND AMPLIFYING
RIDGING OVER THE WEST COAST. AN ANOMALOUS MID-LEVEL TROUGH AND ASSOCIATED
NEGATIVE 500-HPA HEIGHT ANOMALIES ARE CENTERED OVER EASTERN CANADA, WHILE
POSITIVE ANOMALIES ARE PREDICTED OVER THE SOUTHEASTERN CONTIGUOUS U.S (CONUS).
MID-LEVEL RIDGING FORECAST ACROSS THE WEST AND TROUGHING OVER THE GREAT LAKES
BRINGS ELEVATED CHANCES FOR BELOW-NORMAL TEMPERATURES ACROSS MUCH OF THE
NORTH-CENTRAL CONUS. THE STRONGEST CHANCES OF BELOW-NORMAL TEMPERATURES ARE
FORECAST PARTS FOR PORTIONS OF THE NORTHERN PLAINS AND UPPER MIDWEST WITH
PROBABILITIES EXCEEDING 50%. ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER MUCH OF
THE WEST COAST, AS WELL AS PORTIONS OF THE SOUTHEAST U.S., CONSISTENT WITH
ENSEMBLE FORECASTS AND REFORECAST TOOLS. IN ALASKA, BELOW-NORMAL TEMPERATURES
ARE FAVORED FOR MOST OF THE MAINLAND WHILE NEAR-NORMAL TEMPERATURES ARE MOST
LIKELY FOR PORTIONS OF THE ALASKA PENINSULA EXTENDING TO THE EASTERN INTERIOR
MAINLAND AND ABOVE-NORMAL TEMPERATURES FAVORED FOR THE PANHANDLE, SUPPORTED BY
MOST OF THE DYNAMICAL TEMPERATURE FORECAST TOOLS. FOR HAWAII (EXCEPT FOR THE
BIG ISLAND), ODDS TILT TOWARDS BELOW-NORMAL TEMPERATURES, CONSISTENT WITH THE
HAWAII CONSOLIDATION (CON) AND TODAY’S AUTOBLEND. NEAR-NORMAL TEMPERATURES ARE
FAVORED FOR THE BIG ISLAND.
BELOW-NORMAL PRECIPITATION IS FAVORED FOR THE WESTERN THIRD OF THE CONUS AS
WELL AS THE NORTHERN PLAINS AND UPPER MIDWEST. THE HIGHEST PROBABILITIES EXCEED
50% ALONG COASTAL LOCATIONS OF NORTHERN CALIFORNIA AND SOUTHERN OREGON.
ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS THE SOUTHERN CONUS EAST OF THE
ROCKIES DUE TO A MOIST GULF RETURN FLOW PREDICTED OVER THE SOUTHERN PLAINS,
CONSISTENT WITH THE GEFS AND ECMWF PRECIPITATION REFORECAST CONSOLIDATION
TOOLS. ODDS ALSO TILT TOWARDS ABOVE-NORMAL PRECIPITATION FOR PORTIONS OF
NORTHERN NEW ENGLAND, UNDER THE INFLUENCE OF AN EXITING MID-LEVEL TROUGH. IN
ALASKA, ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF THE MAINLAND WITH
BELOW-NORMAL PRECIPITATION FAVORED IN PARTS OF THE CENTRAL ALEUTIANS. IN
HAWAII, ODDS TILT SLIGHTLY TOWARDS BELOW-NORMAL PRECIPITATION, CONSISTENT WITH
THE HAWAII CON.
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: BELOW AVERAGE, 2 OUT OF 5, WITH
MODERATE AGREEMENT AMONG FORECAST MODELS AND TOOLS, OFFSET BY LARGE CHANGES IN
MODEL SOLUTIONS RELATIVE TO YESTERDAY AND A SYNOPTIC REGIME CHANGE FAVORED
DURING THE FORECAST PERIOD.
8-14 DAY OUTLOOK FOR APR 20 - 26 2024
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY (WEEK-2) PERIOD PREDICT A
DE-AMPLIFICATION OF THE 500-HPA CIRCULATION PATTERN RELATIVE TO THE 6-10 DAY
PERIOD ACROSS NORTH AMERICA AND THE SURROUNDING REGIONS. HEIGHT ANOMALIES ARE
MUCH WEAKER RELATIVE TO THE 6-10 DAY PERIOD AS THE SYNOPTIC PATTERN BECOMES
MORE ZONAL AND SPREAD AMONG MODEL SOLUTIONS INCREASES. DURING WEEK-2, STRONG
POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST TO BE CENTERED OVER THE
KAMCHATKA PENINSULA OF EASTERN RUSSIA WITH POSITIVE ANOMALIES EXTENDING ACROSS
THE BERING SEA. WEAK NEGATIVE ANOMALIES ARE FORECAST OVER NORTHEASTERN ALASKA
AND THE CHUKCHI SEA. WEAK RIDGING WITH POSITIVE 500-HPA HEIGHT ANOMALIES ARE
FAVORED OVER THE NORTHERN AND NORTHWESTERN CONUS, AND A WEAK TROUGH IS DEPICTED
OVER THE CANADIAN MARITIMES LEADING TO BELOW-NORMAL MID-LEVEL HEIGHTS OVER
PORTIONS OF THE NORTHEAST.
ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER MUCH OF THE WESTERN CONUS DUE THE
FORECAST RIDGING AND ABOVE-NORMAL 500-HPA HEIGHTS OVER WESTERN NORTH AMERICA.
ABOVE-NORMAL TEMPERATURE CHANCES EXCEEDING 50% ARE INDICATED FOR PORTIONS OF
THE GREAT BASIN, AND ODDS TILT TOWARDS ABOVE-NORMAL TEMPERATURES FOR FLORIDA,
AS INDICATED BY THE MAJORITY OF FORECAST GUIDANCE. BELOW-NORMAL TEMPERATURES
ARE FAVORED FOR PORTIONS OF THE UPPER MIDWEST, GREAT LAKES, AND PARTICULARLY
THE TENNESSEE AND OHIO VALLEYS (>50% PROBABILITY CENTERED OVER THE OHIO VALLEY)
SUPPORTED BY MOST DYNAMIC TEMPERATURE FORECAST TOOLS. BELOW-NORMAL TEMPERATURES
ARE ALSO FAVORED FOR THE SOUTHERN PLAINS AND LOWER MISSISSIPPI VALLEY WHERE
ENHANCED PRECIPITATION MAY LIMIT DAYTIME HEATING. IN ALASKA, BELOW-NORMAL
TEMPERATURES REMAIN FAVORED ACROSS MOST OF THE STATE, CONSISTENT WITH THE GEFS
CALIBRATED REFORECAST TOOL, WHILE NEAR-NORMAL TEMPERATURES ARE MOST LIKELY FOR
THE PANHANDLE. IN HAWAII, NEAR-NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE
STATE, WHILE OAHU AND KAUAI LEAN TOWARDS BELOW-NORMAL TEMPERATURES.
THE WEEK-2 PRECIPITATION FORECAST IS FAIRLY PROGRESSIVE, RELATIVE TO THE 6-10
DAY FORECAST, WITH CHANCES FOR BELOW-NORMAL PRECIPITATION SHIFTING FROM THE
NORTHERN PLAINS TO THE NORTHEASTERN CONUS, WHILE A DEVELOPING RETURN FLOW
PATTERN BRINGS CHANCES FOR ABOVE-NORMAL PRECIPITATION TO THE GULF COAST,
SOUTHERN AND CENTRAL PLAINS AND PORTIONS OF THE FOUR CORNERS REGION.
BELOW-NORMAL PRECIPITATION REMAINS FAVORED FOR THE NORTHWESTERN CONUS WITH
RIDGING DEPICTED OVER THE WEST COAST. PROBABILITIES ARE LOWER OVERALL THAN
YESTERDAY’S OUTLOOKS, REFLECTING THE INCREASED UNCERTAINTY IN TODAY’S FORECAST.
IN ALASKA, ABOVE-NORMAL PRECIPITATION REMAINS FAVORED ACROSS MUCH OF THE STATE,
WHILE NEAR-NORMAL PRECIPITATION IS MOST LIKELY FOR THE PARTS OF THE CENTRAL AND
WESTERN ALEUTIANS AND THE PANHANDLE. IN HAWAII BELOW-NORMAL PRECIPITATION IS
ONCE AGAIN SLIGHTLY FAVORED, CONSISTENT WITH THE HAWAII CON.
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: BELOW AVERAGE, 2 OUT OF 5, WITH
MODERATE AGREEMENT AMONG FORECAST MODELS AND TOOLS, OFFSET BY A FAIRLY
PROGRESSIVE PATTERN AND WEAK ANOMALIES IN ENSEMBLE FORECASTS.
FORECASTER: DANIEL BARANDIARAN
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 18.
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:
20080411 - 19770418 - 19640426 - 19550412 - 19990405
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:
20080410 - 19770419 - 19640425 - 19550412 - 19610418
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 18 - 22 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A B
SRN CALIF A B IDAHO N B NEVADA A B
W MONTANA N B E MONTANA B B WYOMING B B
UTAH N B ARIZONA A B COLORADO N N
NEW MEXICO N A N DAKOTA B B S DAKOTA B B
NEBRASKA B B KANSAS B N OKLAHOMA B A
N TEXAS N A S TEXAS N A W TEXAS N A
MINNESOTA B B IOWA B B MISSOURI B N
ARKANSAS B A LOUISIANA N A WISCONSIN B B
ILLINOIS B N MISSISSIPPI N A MICHIGAN B N
INDIANA B N OHIO B N KENTUCKY B N
TENNESSEE N N ALABAMA N A NEW YORK N N
VERMONT N N NEW HAMP N N MAINE N A
MASS N N CONN N N RHODE IS N N
PENN N N NEW JERSEY N N W VIRGINIA N N
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA A N S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A N AK N SLOPE B A
AK ALEUTIAN B N AK WESTERN B A AK INT BSN B A
AK S INT N A AK SO COAST N A AK PNHDL A N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 20 - 26 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON A N NRN CALIF A N
SRN CALIF A N IDAHO A N NEVADA A N
W MONTANA A N E MONTANA A N WYOMING A N
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A N S DAKOTA A N
NEBRASKA A A KANSAS N A OKLAHOMA B A
N TEXAS B A S TEXAS B A W TEXAS B A
MINNESOTA N N IOWA B N MISSOURI B N
ARKANSAS B N LOUISIANA B A WISCONSIN N B
ILLINOIS B B MISSISSIPPI B N MICHIGAN B B
INDIANA B B OHIO B B KENTUCKY B B
TENNESSEE B N ALABAMA B N NEW YORK B B
VERMONT B B NEW HAMP B B MAINE B B
MASS B B CONN B B RHODE IS B B
PENN B B NEW JERSEY B B W VIRGINIA B B
MARYLAND B B DELAWARE B B VIRGINIA B B
N CAROLINA B N S CAROLINA B N GEORGIA B A
FL PNHDL N A FL PENIN A A 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 N 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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