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FXUS06 KWBC 152013
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI NOVEMBER 15 2024
6-10 DAY OUTLOOK FOR NOV 21 - 25 2024
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE MEAN 500-HPA FLOW
PATTERN FORECAST ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING THE 6-10
DAY PERIOD. A HIGH AMPLITUDE RIDGE IS PREDICTED OVER THE ALEUTIAN ISLANDS,
WHILE A TROUGH IS PREDICTED DOWNSTREAM OVER THE NORTHEASTERN PACIFIC OCEAN NEAR
THE WEST COAST OF NORTH AMERICA. AS THE TROUGH MOVES INTO THE WESTERN CONUS
LATER IN THE PERIOD, A SECOND TROUGH IS PREDICTED TO MOVE FROM THE EASTERN
CONTIGUOUS U.S. (CONUS) INTO THE ATLANTIC DURING THE PERIOD. THE GEFS MODEL
PREDICTS A MORE AMPLIFIED TROUGH OVER THE EASTERN CONUS EARLY IN THE PERIOD
RELATIVE TO THE ECMWF MODEL FORECAST. A RIDGE AND ASSOCIATED POSITIVE 500-HPA
HEIGHT ANOMALIES ARE PREDICTED OVER THE WESTERN CONUS ON AVERAGE FOR THE 6-10
DAY PERIOD.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR NORTHWESTERN AND NORTHERN MAINLAND
ALASKA, CONSISTENT WITH POSITIVE 500-HPA HEIGHT ANOMALIES AND DECADAL
TEMPERATURE TRENDS. BELOW NORMAL TEMPERATURES ARE LIKELY FOR SOUTHEASTERN
ALASKA, UNDER ANOMALOUS NORTHERLY FLOW. ABOVE NORMAL TEMPERATURES ARE NOW
FAVORED OVER MOST OF THE WESTERN CONUS, WITH THE RAPID EASTWARD PROGRESSION OF
A PREDICTED RIDGE. BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE SOUTHEASTERN
CONUS UNDER A MEAN TROUGH, CONSISTENT WITH GEFS TEMPERATURE FORECASTS, WHICH
ARE MORE CONSISTENT WITH YESTERDAY’S FORECAST PATTERN. ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR THE NORTHERN GREAT LAKES REGION AND NORTHEAST,
WITH THE WARMEST TEMPERATURES PRIMARILY IN THE FIRST HALF OF THE PERIOD RELATED
TO POSITIVE 500-HPA HEIGHT ANOMALIES. NEAR NORMAL TEMPERATURES ARE FORECAST FOR
HAWAII, WHERE ECMWF AND GEFS TOOLS ARE INCONSISTENT.
ABOVE NORMAL PRECIPITATION IS FAVORED FOR CENTRAL AND NORTHERN MAINLAND ALASKA,
UNDER STRONG WESTERLY MID-LEVEL FLOW. BELOW NORMAL PRECIPITATION IS FAVORED FOR
SOUTHERN ALASKA, UNDER ANOMALOUS NORTHERLY FLOW. ABOVE NORMAL PRECIPITATION IS
NOW FAVORED OVER A LARGE AREA OF THE PACIFIC COAST AND NORTHWESTERN CONUS,
AHEAD OF THE PREDICTED TROUGH. THE AREA OF LIKELY BELOW NORMAL PRECIPITATION
HAS SHIFTED EASTWARD FROM YESTERDAY’S FORECASTS TO THE SOUTHERN CENTRAL AND
SOUTHEASTERN CONUS, UNDER ANOMALOUS NORTHERLY FLOW. ABOVE NORMAL PRECIPITATION
IS FAVORED FOR THE NORTHEAST, WITH A TROUGH PREDICTED OVER THE EASTERN CONUS.
ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR HAWAII, CONSISTENT WITH THE
PRECIPITATION CONSOLIDATION.
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: BELOW AVERAGE, 2 OUT OF 5, DUE TO
GENERAL AGREEMENT ON THE MEAN CIRCULATION FORECAST FOR THE PERIOD, OFFSET BY A
RAPIDLY CHANGING PATTERN AND DIFFERENCES AMONG THE MODEL TEMPERATURE AND
PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR NOV 23 - 29 2024
THE CHANGING 500-HPA HEIGHT PATTERN FORECAST CONTINUES INTO THE WEEK 2 PERIOD,
WITH INCREASING DIFFERENCES BETWEEN MODELS AND DEAMPLIFICATION OF MOST
ANOMALIES IN ENSEMBLE MEAN FORECASTS, DUE TO INCREASING ENSEMBLE SPREAD. THE
GEFS MODEL PERSISTS NEGATIVE 500-HPA HEIGHT ANOMALIES OVER THE EASTERN CONUS
LONGER INTO THE PERIOD, BEFORE BOTH THE GEFS AND ECMWF MODELS PREDICT
PROGRESSION OF THIS TROUGH INTO THE NORTH ATLANTIC. ENSEMBLE MEANS PREDICT A
POSITIVE 500-HPA HEIGHT ANOMALY CENTERED OVER THE BERING SEA AND PRIMARILY
NORTHERLY FLOW OVER MUCH OF ALASKA. A PREDICTED TROUGH OVER THE NORTHEASTERN
PACIFIC MOVES INTO THE WESTERN CONUS DURING WEEK 2. THE MANUAL BLEND PREDICTS
MEAN POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE CENTRAL CONUS AND NEGATIVE
500-HPA HEIGHT ANOMALIES OVER THE EASTERN CONUS AND NEAR THE WEST COAST.
BELOW NORMAL TEMPERATURES ARE FAVORED FOR SOUTHEASTERN MAINLAND ALASKA AND
SOUTHEAST ALASKA IN WEEK 2, UNDER NORTHERLY FLOW. NEAR TO ABOVE NORMAL
TEMPERATURES ARE SLIGHTLY FAVORED FOR MUCH OF THE WEST, CONSISTENT WITH
REFORECAST-CALIBRATED GEFS AND ECMWF FORECASTS, WHILE ABOVE NORMAL TEMPERATURES
ARE LIKELY FOR A LARGE AREA OF THE SOUTHWEST INTO THE SOUTHERN PLAINS, UNDER A
PREDICTED RIDGE, INDICATING A RAPID WARM-UP AS THE PATTERN PROGRESSES EASTWARD.
BELOW NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE SOUTHEAST, UNDER A
PREDICTED MEAN TROUGH AND NORTHERLY FLOW. ABOVE NORMAL TEMPERATURES CONTINUE TO
BE FAVORED FOR THE NORTHERN GREAT LAKES REGION AND NORTHEAST, SUPPORTED BY MOST
DYNAMICAL MODEL TEMPERATURE FORECASTS. ABOVE NORMAL TEMPERATURES ARE FAVORED
FOR HAWAII CONSISTENT WITH THE TEMPERATURE CONSOLIDATION.
ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED ACROSS NORTHERN MAINLAND ALASKA,
CONSISTENT WITH MOST DYNAMICAL MODEL FORECASTS, WHILE BELOW NORMAL
PRECIPITATION IS FAVORED FOR SOUTHERN ALASKA UNDER NORTHERLY FLOW. ABOVE NORMAL
PRECIPITATION CONTINUES TO BE FAVORED ACROSS A LARGE AREA OF THE WESTERN CONUS
INTO THE NORTHERN PLAINS, AHEAD OF THE PREDICTED TROUGH. BELOW NORMAL
PRECIPITATION IS SLIGHTLY FAVORED ACROSS A LARGE AREA OF THE SOUTHERN CENTRAL
CONUS, UNDER THE PREDICTED RIDGE. BELOW NORMAL PRECIPITATION IS FAVORED FOR THE
SOUTHEAST AND NORTHWARD UP THE ATLANTIC COAST, UNDER A DRIER PATTERN BEHIND THE
EASTWARD PROGRESSING TROUGH. THE PRECIPITATION CONSOLIDATION FAVORS ABOVE
NORMAL PRECIPITATION ACROSS HAWAII.
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: WELL BELOW AVERAGE, 1 OUT OF 5,
DUE TO MODEL FORECAST DIFFERENCES ON A RAPIDLY CHANGING MID-LEVEL HEIGHT
PATTERN.
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
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:
19721108 - 20001027 - 19901119 - 20041026 - 19941113
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:
20041025 - 19721107 - 20001028 - 19941111 - 19901118
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 21 - 25 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA A A E MONTANA N A WYOMING A A
UTAH A N ARIZONA A N COLORADO A B
NEW MEXICO A B N DAKOTA N N S DAKOTA N N
NEBRASKA N B KANSAS N B OKLAHOMA N B
N TEXAS N B S TEXAS N B W TEXAS A B
MINNESOTA N N IOWA N B MISSOURI B B
ARKANSAS B B LOUISIANA B B WISCONSIN N N
ILLINOIS B B MISSISSIPPI B B MICHIGAN A A
INDIANA B N OHIO B A KENTUCKY B N
TENNESSEE B B ALABAMA B B 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 N A NEW JERSEY N A W VIRGINIA B A
MARYLAND N N DELAWARE N N VIRGINIA B N
N CAROLINA B B S CAROLINA B B GEORGIA B B
FL PNHDL B B FL PENIN B B AK N SLOPE A A
AK ALEUTIAN A B AK WESTERN A A AK INT BSN A A
AK S INT N B AK SO COAST N B AK PNHDL B B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 23 - 29 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON A A NRN CALIF A A
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA N A E MONTANA N A WYOMING A A
UTAH A A ARIZONA A N COLORADO A N
NEW MEXICO A B N DAKOTA N A S DAKOTA N A
NEBRASKA A N KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A A IOWA N N MISSOURI N B
ARKANSAS A B LOUISIANA A B WISCONSIN A N
ILLINOIS N N MISSISSIPPI N B MICHIGAN A N
INDIANA N N OHIO N N KENTUCKY N N
TENNESSEE B B ALABAMA N B NEW YORK A N
VERMONT A B NEW HAMP A B MAINE A N
MASS A B CONN N B RHODE IS N B
PENN N B NEW JERSEY N B W VIRGINIA B B
MARYLAND N B DELAWARE N B VIRGINIA B B
N CAROLINA B B S CAROLINA B B GEORGIA B B
FL PNHDL B B FL PENIN B B AK N SLOPE N A
AK ALEUTIAN N B AK WESTERN N N AK INT BSN B A
AK S INT B B AK SO COAST B B AK PNHDL B B
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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