824
FXUS06 KWBC 292005
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST THU FEBRUARY 29 2024
6-10 DAY OUTLOOK FOR MAR 06 - 10 2024
DYNAMICAL MODELS ARE IN FAIR AGREEMENT TODAY ON THE POSITIONING OF THE MEAN
500-HPA HEIGHT PATTERN DURING THE 6-10 DAY PERIOD. HOWEVER, THERE ARE
DIFFERENCES AMONG THE RELATIVE STRENGTHS OF THE HEIGHT ANOMALIES IN WESTERN
NORTH AMERICA, WITH THE WEAKER SOLUTION BELONGING TO THE ECMWF AND A MORE
AMPLIFIED SOLUTION FROM THE GEFS. THE MANUAL 500-HPA HEIGHT BLEND HAS STRONG
POSITIVE 500-HPA HEIGHT ANOMALIES FORECAST FOR THE CENTRAL NORTH PACIFIC AND
OVER EASTERN NORTH AMERICA CENTERED OVER THE CANADIAN MARITIMES. MEANWHILE, AN
AREA OF MEAN NEGATIVE 500-HPA HEIGHT ANOMALIES IS FORECAST OVER WESTERN NORTH
AMERICA FROM ALASKA TO NORTHERN MEXICO. THE GEFS FORECASTS THE RELOADING OF THE
WESTERN TROUGH BY THE MIDDLE OF THE PERIOD. HOWEVER, THE ECMWF IS MORE
PROGRESSIVE AND INTRODUCES WEAK RIDGING INTO THE WEST COAST. THIS DRIVES LARGE
DIFFERENCES IN THE PRECIPITATION FORECAST FROM THESE DYNAMICAL MODELS. IN
HAWAII, NEAR TO SLIGHTLY BELOW-NORMAL 500-HPA HEIGHTS ARE FORECAST DURING THE
6-10 DAY PERIOD.
BELOW-NORMAL TEMPERATURES ARE MOST LIKELY FOR MOST OF THE WESTERN CONTIGUOUS
U.S. (CONUS), UNDER THE PREDICTED TROUGH. PROBABILITIES OF BELOW-NORMAL
TEMPERATURES EXCEED 60 PERCENT FOR MUCH OF CALIFORNIA AND WESTERN NEVADA.
ABOVE-NORMAL TEMPERATURES ARE LIKELY FROM THE GREAT PLAINS TO THE ATLANTIC.
PROBABILITIES OF ABOVE-NORMAL TEMPERATURES EXCEED 80 PERCENT FOR MUCH OF THE
EASTERN GREAT LAKES REGION AND NORTHEAST. NEAR- TO SLIGHTLY BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR HAWAII, CONSISTENT WITH AUTOMATED AND
CONSOLIDATION TEMPERATURE TOOLS. IN ALASKA, BELOW-NORMAL TEMPERATURES ARE
FAVORED ACROSS NORTHERN PORTIONS OF THE STATE WITH BETTER AGREEMENT AMONG THE
DYNAMICAL REFORECAST TOOLS. NEAR-NORMAL IS FAVORED ACROSS THE SOUTHEAST
MAINLAND AND SOUTHEAST ALASKA DURING THE PERIOD WITH MORE DISAGREEMENT AMONG
THE DYNAMICAL REFORECAST TOOLS REDUCING CONFIDENCE.
THE PREDICTED CIRCULATION PATTERN OVER ALASKA FAVORS ABOVE-NORMAL PRECIPITATION
FROM SOUTH-CENTRAL MAINLAND ALASKA THROUGH MUCH OF SOUTHEAST ALASKA, WHILE
BELOW-NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR THE NORTHWESTERN MAINLAND.
ABOVE-NORMAL PRECIPITATION IS FAVORED FOR MUCH OF THE CONUS DURING THE PERIOD
AS THE PREDICTED TROUGH PROGRESSES ACROSS THE COUNTRY. THE HIGHEST
PROBABILITIES OF ABOVE-NORMAL PRECIPITATION ARE FORECAST FOR CALIFORNIA WITH
CHANCES EXCEEDING 50% ACROSS THE STATE. PROBABILITIES EXCEEDING 50% ARE ALSO
FORECAST IN THE CENTRAL PLAINS WHERE LEE-SIDE CYCLOGENESIS MAY OCCUR, AND ALONG
THE EASTERN SEABOARD, WHERE A LOW-PRESSURE SYSTEM AND ASSOCIATED FRONTAL SYSTEM
IS FORECAST TO CROSS THE REGION EARLY IN THE PERIOD. NEAR-NORMAL PRECIPITATION
IS SLIGHTLY FAVORED FOR MUCH OF HAWAII CONSISTENT WITH THE CONSOLIDATION AND
BLENDED PRECIPITATION FORECASTS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 40% OF TODAY'S 6Z GFS
ENSEMBLE 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: ABOUT-AVERAGE, 3 OUT OF 5, DUE TO
FAIR AGREEMENT AMONG ALL THE MODEL TOOLS FOR MUCH OF THE COUNTRY OFFSET BY THE
LARGE DIFFERENCE IN 500-HPA HEIGHT ANOMALIES ACROSS WESTERN NORTH AMERICA.
8-14 DAY OUTLOOK FOR MAR 08 - 14 2024
THERE IS A FAIR AMOUNT OF UNCERTAINTY IN THE WEEK-2 FORECAST. DYNAMICAL TOOLS
HAVE LIMITED AGREEMENT IN THE EVOLUTION OF THE 500-HPA HEIGHT PATTERN,
PARTICULARLY ACROSS WESTERN NORTH AMERICA. AT THE ONSET OF THE PERIOD, THE GEFS
IS DEVELOPING A RELOADING TROUGH IMPACTING THE WEST COAST. HOWEVER, THE ECMWF
HAS WEAK RIDGING IN THIS VICINITY, WITH A WIDE RANGE OF POSSIBLE SOLUTIONS
NOTED IN ITS ENSEMBLE FORECASTS. AT THE VERY LEAST, IT SEEMS MOST LIKELY THAT
THERE WILL BE AT LEAST TWO WAVES OF MID-LEVEL LOW PRESSURE ROTATING THROUGH THE
WEST. WITH THE FIRST PROGRESSING ACROSS THE CONUS BEFORE MID-LEVEL HIGH
PRESSURE IS FORECAST TO BECOME RE-ESTABLISHED ACROSS THE EAST BY THE END OF THE
PERIOD. IN ALASKA, BELOW-NORMAL 500-HPA HEIGHTS ARE FORECAST FOR MUCH OF THE
WEEK-2 PERIOD. IN HAWAII, NEAR TO ABOVE-NORMAL MID-LEVEL HEIGHTS ARE FORECAST.
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 UPPER NORTHEAST, WHILE
PROBABILITIES ARE MORE MODEST OVER THE SOUTHEAST, WHERE 500-HPA HEIGHT
ANOMALIES ARE PREDICTED TO DROP TO NEAR-NORMAL DURING THE PERIOD. BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR MOST OF HAWAII, CONSISTENT WITH THE AUTOMATED
TEMPERATURE BLEND AND THE CONSOLIDATION.
AS IN THE 6-10 DAY PERIOD, MUCH OF THE CONUS IS FAVORED TO SEE ABOVE-NORMAL
PRECIPITATION DURING THE WEEK-2 PERIOD. IN THE EAST, A STALLED FRONTAL SYSTEM
IS FORECAST TO DEVELOP AND BRING A PERIOD OF PRECIPITATION TO MUCH OF THE
EASTERN CONUS DURING THE EARLY AND MIDDLE OF THE WEEK. MEANWHILE, IN THE
PLAINS, LEE-SIDE CYCLOGENESIS IS FORECAST AND THE MID-LATITUDE CYCLONE WILL
PROGRESS NORTHEAST ACROSS THE PLAINS INTO THE GREAT LAKES. FINALLY, RESIDUAL
PRECIPITATION FROM THE TROUGH AND LOW CLIMATOLOGIES IN SOUTHERN CALIFORNIA
BRING HIGHER CHANCES FOR ABOVE-NORMAL PRECIPITATION TO THE AREA. IN ALASKA,
ABOVE-NORMAL PRECIPITATION IS GENERALLY FAVORED ACROSS SOUTHERN ALASKA WITH THE
HIGHEST CHANCES FROM SOUTH-CENTRAL ALASKA THROUGH THE COPPER RIVER BASIN. IN
HAWAII, BELOW-NORMAL PRECIPITATION IS GENERALLY FAVORED CONSISTENT WITH THE
AUTOBLEND AND CONSOLIDATION TOOLS.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 40% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 30% 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: BELOW-AVERAGE, 2 OUT OF 5, DUE TO
ONLY FAIR AGREEMENT BETWEEN THE DYNAMICAL TOOLS ON THE 500-HPA HEIGHT PATTERN,
PARTICULARLY IN THE WESTERN CONUS, OFFSET FAIR AGREEMENT IN SENSIBLE WEATHER
TOOLS.
FORECASTER: RYAN BOLT
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:
19940210 - 19900211 - 19820310 - 19740302 - 19640310
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:
19740302 - 19940210 - 19900208 - 19760219 - 19820311
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 06 - 10 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 B N E MONTANA N B WYOMING B A
UTAH B 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 A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA A N 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 B N
AK ALEUTIAN B A AK WESTERN B N AK INT BSN B N
AK S INT N A AK SO COAST N A AK PNHDL N A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 08 - 14 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 B A E MONTANA A N WYOMING B A
UTAH B 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 A A
N TEXAS A A S TEXAS A N W TEXAS N 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 B N
AK ALEUTIAN B A AK WESTERN B N AK INT BSN B N
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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