721
FXUS06 KWBC 192002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE NOVEMBER 19 2024
6-10 DAY OUTLOOK FOR NOV 25 - 29 2024
DURING THE 6-10 DAY PERIOD MODELS REMAIN IN FAIRLY GOOD AGREEMENT RELATIVE TO
YESTERDAY ON AN AMPLIFIED AND PROGRESSIVE MID-LEVEL HEIGHT PATTERN ACROSS NORTH
AMERICA AND THE SURROUNDING REGIONS. STRONG POSITIVE 500-HPA HEIGHT ANOMALIES
HAVE SHIFTED SOUTHEAST INTO THE GULF OF ALASKA RELATIVE TO YESTERDAY’S ANOMALY
CENTER OVER THE BERING SEA. THIS SHIFTS THE OVERALL FLOW PATTERN ACROSS ALASKA.
MEANWHILE, A FAST MOVING MID-LEVEL TROUGH IS FORECAST TO PROGRESS FROM THE
INTERIOR WEST ACROSS MUCH OF THE CONTIGUOUS U.S. (CONUS) DURING THE 6-10 DAY
PERIOD. THIS TROUGH WILL DISPLACE POSITIVE MID-LEVEL HEIGHT ANOMALIES ACROSS
THE EASTERN CONUS AS THE PERIOD PROGRESSES LEAVING THE POSITIVE 6-10 DAY MEAN
HEIGHT ANOMALIES ONLY IN THE SOUTHEASTERN AND SOUTH-CENTRAL CONUS.
ABOVE-NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH OF THE SOUTHERN AND EASTERN
CONUS DURING THE 6-10 DAY PERIOD BENEATH POSITIVE 500-HPA HEIGHT ANOMALIES
AHEAD OF AN APPROACHING MID-LEVEL TROUGH. THERE IS GOOD AGREEMENT BETWEEN THE
RAW, SHORT-TERM BIAS-CORRECTED, AND REFORECAST TOOLS FROM THE GEFS AND ECENS
ACROSS THESE REGIONS. BELOW-NORMAL TEMPERATURE CHANCES ARE ENHANCED ACROSS MUCH
OF THE WESTERN CONUS AND INTO THE NORTHERN AND CENTRAL PLAINS. THIS IS
CONSISTENT WITH DYNAMICAL AND STATISTICAL GUIDANCE. IN ALASKA, THE CHANGE IN
THE FORECAST LOCATION OF A MID-LEVEL RIDGE IS SHIFTING THE TEMPERATURE FORECAST
WITH MANY TOOLS BEGINNING TO INDICATE ABOVE-NORMAL TEMPERATURE CHANCES
DEVELOPING AND REDUCED CHANCES FOR BELOW-NORMAL TEMPERATURES ACROSS MUCH OF THE
STATE. THERE REMAINS CONSIDERABLE DISAGREEMENT HOWEVER, AND LARGE AREAS OF
NEAR-NORMAL ARE FAVORED ACROSS MUCH OF MAINLAND ALASKA, WITH REDUCED CHANCES,
RELATIVE TO YESTERDAY, FOR BELOW-NORMAL ACROSS SOUTHEAST ALASKA. IN HAWAII,
TOOLS ARE IN VERY STRONG AGREEMENT FOR ABOVE-NORMAL TEMPERATURES.
A GENERALLY WET PATTERN IS PREDICTED ACROSS THE CONUS DURING THE 6-10 DAY
PERIOD. THE STRONGEST CHANCES ARE ACROSS PORTIONS OF THE CENTRAL ROCKIES WITH
THE MID-LEVEL TROUGH FORECAST TO BE FURTHER INLAND RELATIVE TO YESTERDAY. THE
MORE EASTERLY PROGRESSION OF THE MID-LEVEL TROUGH REDUCES CHANCES FOR
ABOVE-NORMAL PRECIPITATION ALONG THE IMMEDIATE WEST COAST AND INTO THE GREAT
BASIN RELATIVE TO YESTERDAY. IN THE EAST ABOVE-NORMAL PRECIPITATION CHANCES ARE
FORECAST ACROSS PORTIONS OF THE OHIO AND TENNESSEE VALLEY WHERE PROBABILITIES
EXCEED 50%. RETURN FLOW OFF THE GULF OF MEXICO IS FORECAST TO INTERACT WITH THE
PROGRESSIVE MID-LEVEL TROUGH BRINGING INCREASED CHANCES FOR PRECIPITATION. NEAR
TO BELOW-NORMAL PRECIPITATION IS FAVORED ACROSS PORTIONS OF FLORIDA AND THE RIO
GRANDE VALLEY, IN AREAS FURTHER REMOVED FROM THE MEAN STORM TRACK. IN ALASKA,
DUE TO THE CHANGE IN THE MID-LEVEL RIDGE GUIDANCE, A WETTER PATTERN IS
FORECAST. HOWEVER, THERE REMAINS SOME DISAGREEMENT AMONG THE TOOLS AND
NEAR-NORMAL IS FAVORED ACROSS MUCH OF SOUTHERN ALASKA, WITH BELOW-NORMAL OVER
PARTS OF SOUTHEAST ALASKA. IN HAWAII, BELOW-NORMAL PRECIPITATION IS FAVORED
CONSISTENT WITH REFORECAST AND BIAS-CORRECTED TOOLS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 10% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 30% OF TODAY'S 6Z 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: AVERAGE, 3 OUT OF 5. GOOD
AGREEMENT AMONG THE DYNAMICAL AND STATISTICAL TOOLS IS OFFSET BY A PROGRESSIVE
AND SHIFTING PATTERN.
8-14 DAY OUTLOOK FOR NOV 27 - DEC 03, 2024
THE PROGRESSIVE MID-LEVEL TROUGH IS FORECAST TO MOVE EAST ACROSS THE CONUS
EARLY IN WEEK-2 AND THEN STALL ACROSS PORTIONS OF THE NORTHEASTERN CONUS BY THE
END OF THE WEEK. POSITIVE MID-LEVEL HEIGHTS ARE FORECAST OFF THE WEST COAST AND
ACROSS MUCH OF ALASKA BRINGING NORTHWESTERLY FLOW INTO MUCH OF THE EASTERN
CONUS FOR MUCH OF WEEK-2. THE ENHANCED POSITIVE MID-LEVEL ANOMALIES ACROSS THE
GULF OF ALASKA CHANGES THE MID-LEVEL FLOW PATTERN ACROSS ALASKA FAIRLY
DRAMATICALLY RELATIVE TO PRIOR FORECASTS. NEAR-NORMAL HEIGHTS ARE FORECAST
ACROSS THE SOUTHERN TIER.
THE NORTHWESTERLY FLOW INTO THE EASTERN CONUS WILL HELP TO ERODE SOME OF THE
POSITIVE TEMPERATURE ANOMALIES SEEN AT THE ONSET OF THE WEEK-2 PERIOD AND IN
THE 6-10 DAY PERIOD. THEREFORE, A COLDER FORECAST IS DEPICTED ACROSS MUCH OF
THE CONUS RELATIVE TO YESTERDAY. ABOVE-NORMAL TEMPERATURE CHANCES ARE LIMITED
TO THE SOUTHEASTERN CONUS WITH THE STRONGEST PROBABILITIES ACROSS FLORIDA.
BELOW-NORMAL TEMPERATURES ARE STRONGLY FAVORED ACROSS PORTIONS OF THE NORTHERN
PLAINS. BETTER AGREEMENT HAS STRENGTHENED PROBABILITIES FOR BELOW-NORMAL
TEMPERATURES INTO PARTS OF THE SOUTHWESTERN CONUS RELATIVE TO YESTERDAY. IN
ALASKA, THE CHANGING FLOW PATTERN REDUCES CHANCES FOR BELOW-NORMAL ACROSS MUCH
OF THE STATE. A LARGE AREA OF NEAR-NORMAL TEMPERATURES ARE FAVORED ACROSS
MAINLAND ALASKA AND INTO SOUTHEAST WITH ONLY LINGERING CHANCES FOR BELOW-NORMAL
TEMPERATURES FAVORED IN FAR SOUTHEAST ALASKA AND NORTHERN ALASKA. IN HAWAII,
ABOVE-NORMAL TEMPERATURES REMAIN FORECAST.
A DRIER PATTERN IS BECOMING MORE ESTABLISHED ACROSS THE WESTERN CONUS BY WEEK-2
AS THE MID-LEVEL TROUGH PROGRESSES EASTWARD AND POSITIVE HEIGHT ANOMALIES BUILD
ACROSS THE NORTHEASTERN PACIFIC. THIS SHOULD REDUCE THE STRENGTH OF ONSHORE
FLOW AND PACIFIC MOISTURE INTO THE CONUS DURING THE PERIOD. AS SUCH, NEAR- TO
BELOW-NORMAL PRECIPITATION IS FAVORED FOR MUCH OF THE WEST, EXCLUDING THE ROCKY
MOUNTAINS, WHERE A SLIGHT TILT TOWARDS ABOVE-NORMAL REMAINS. IN THE EAST,
ABOVE-NORMAL IS GENERALLY FAVORED AS THE TROUGH PROGRESSES EASTWARD AND
INTERACTS WITH MOISTURE FROM THE GULF OF MEXICO. THERE IS GOOD AGREEMENT FOR
PRECIPITATION AHEAD OF THE TROUGH. IN ALASKA, THE MORE ZONAL FLOW INCREASES
PRECIPITATION CHANCES RELATIVE TO YESTERDAY, WITH MUCH OF MAINLAND ALASKA
FAVORED TO SEE ABOVE-NORMAL PRECIPITATION, EXCLUDING THE SOUTHERN COASTAL
MAINLAND AND SOUTHEAST ALASKA WHERE NEAR-NORMAL REMAINS FAVORED. IN HAWAII,
BELOW-NORMAL PRECIPITATION IS GENERALLY FAVORED IN MOST LOCATIONS.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 10% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 30% OF TODAY'S 6Z 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: AVERAGE, 3 OUT OF 5, GOOD
AGREEMENT BETWEEN MANY OF THE FORECAST TOOLS IS OFFSET BY REDUCED ANOMALIES IN
THE HEIGHT PATTERN.
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
NOVEMBER 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:
19941112 - 19731119 - 19731125 - 20031117 - 19611123
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:
19731125 - 19941111 - 19731118 - 20031117 - 19611122
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 25 - 29 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B N OREGON B N NRN CALIF B A
SRN CALIF B A IDAHO B A NEVADA B A
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B A ARIZONA B A COLORADO B A
NEW MEXICO N A N DAKOTA B A S DAKOTA B A
NEBRASKA B A KANSAS B A OKLAHOMA A A
N TEXAS A A S TEXAS A N W TEXAS A A
MINNESOTA B A IOWA B A MISSOURI N A
ARKANSAS A A LOUISIANA A A WISCONSIN N A
ILLINOIS N 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 N
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 N AK N SLOPE B A
AK ALEUTIAN A N AK WESTERN A A AK INT BSN N A
AK S INT N N AK SO COAST N N AK PNHDL B B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 27 - DEC 03, 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B N OREGON B N NRN CALIF B N
SRN CALIF B N IDAHO B N NEVADA B N
W MONTANA B A E MONTANA B N WYOMING B A
UTAH B N ARIZONA B B COLORADO B A
NEW MEXICO B N N DAKOTA B N S DAKOTA B N
NEBRASKA B N KANSAS B N OKLAHOMA B N
N TEXAS N N S TEXAS A N W TEXAS N N
MINNESOTA B N IOWA B N MISSOURI B N
ARKANSAS N A LOUISIANA A A WISCONSIN B N
ILLINOIS B N MISSISSIPPI A A MICHIGAN B A
INDIANA B A OHIO N A KENTUCKY N A
TENNESSEE N A ALABAMA A A NEW YORK N A
VERMONT N N NEW HAMP N N MAINE N N
MASS N N CONN N A RHODE IS N A
PENN N A NEW JERSEY N A W VIRGINIA N A
MARYLAND N A DELAWARE N A VIRGINIA N A
N CAROLINA A A S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN A N AK WESTERN A N AK INT BSN N A
AK S INT N A AK SO COAST N N 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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