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FXUS06 KWBC 112003
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST MON NOVEMBER 11 2024
6-10 DAY OUTLOOK FOR NOV 17 - 21 2024
TODAY'S EUROPEAN AND CANADIAN ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT IN
DEPICTING A HIGHLY AMPLIFIED MEAN 500-HPA FLOW PATTERN ACROSS NORTH AMERICA AND
SURROUNDING REGIONS (PARTICULARLY IN THE BEGINNING OF THE PERIOD). MODERATE TO
HIGH AMPLITUDE TROUGHS ARE DEPICTED ACROSS ALASKA AND THE WESTERN CONUS, WHILE
RIDGING DOMINATES MUCH OF THE CONUS EAST OF THE MISSISSIPPI. THE 6Z GEFS,
HOWEVER, FORECASTS A SIGNIFICANTLY MORE PROGRESSIVE PATTERN WITH AN EASTERN
DISPLACEMENT OF THE TROUGH OVER THE CONUS TOWARD THE PLAINS STATES. ALL
ENSEMBLE MEAN SOLUTIONS FORECAST A TROUGH OR CLOSED LOW OFF OF THE EASTERN
SEABOARD AND WELL ABOVE NORMAL HEIGHTS CENTERED NEAR THE DAVIS STRAIT,
CONSISTENT WITH THE NEGATIVE PHASE OF THE NAO. BY THE END OF THE 6-10 DAY
PERIOD, THE MAIN LONGWAVE FEATURES ARE FORECAST TO PROGRESS EASTWARD
SIGNIFICANTLY, FORESHADOWING A TRANSITIONAL PATTERN DURING THE WEEK-2 PERIOD.
THE 500-HPA OFFICIAL MANUAL BLEND LEANS TOWARD THE EUROPEAN AND CANADIAN
ENSEMBLE MEAN SOLUTIONS, DUE TO THE RELATIVE CONSISTENCY BETWEEN THESE MODELS.
THE HIGHLY AMPLIFIED PATTERN PREDICTED EARLY IN THE PERIOD LEADS TO COLDER THAN
NORMAL TEMPERATURES BEING FAVORED ACROSS MOST OF ALASKA AND THE WESTERN THIRD
OF THE CONUS. PROBABILITIES OF BELOW NORMAL TEMPERATURES EXCEED 70 PERCENT
ACROSS PARTS OF THE SOUTHWESTERN CONUS AND GREAT BASIN. HOWEVER, TEMPERATURES
ARE LIKELY TO MODERATE ACROSS MUCH OF THESE AREAS TOWARD THE END OF THE PERIOD
AS THE PATTERN BECOMES MORE PROGRESSIVE. CONVERSELY, ABOVE NORMAL TEMPERATURES
ARE LIKELY ACROSS THE EASTERN HALF OF THE COUNTRY DUE TO ANOMALOUS RIDGING AND
ABOVE NORMAL HEIGHTS, WITH A GREATER THAN 80 PERCENT CHANCE OF ABOVE NORMAL
TEMPERATURES NOTED ACROSS PARTS OF THE GREAT LAKES REGION. THESE FAVORED ABOVE
NORMAL TEMPERATURES ARE FORECAST TO ERODE FROM WEST TO EAST AS THE PATTERN
BECOMES MORE PROGRESSIVE LATE IN THE PERIOD. A REDUCTION OF ABOVE NORMAL
TEMPERATURE PROBABILITIES ARE ALSO NOTED FOR HAWAII, CONSISTENT WITH THE SKILL
WEIGHTED CONSOLIDATION OF THE EUROPEAN AND GEFS ENSEMBLES.
THE PROGRESSION OF AN AMPLIFIED TROUGH FROM THE WESTERN CONUS FAVORS A LARGE
SWATH OF ABOVE NORMAL PRECIPITATION ACROSS MUCH OF THE CENTRAL CONUS.
PROBABILITIES OF ABOVE NORMAL PRECIPITATION EXCEED 60 PERCENT FOR PARTS OF THE
CENTRAL AND SOUTHERN PLAINS NEAR THE PREDICTED MEAN BAROCLINIC ZONE. A
SECONDARY AREA OF FAVORED ABOVE NORMAL PRECIPITATION IS INDICATED FOR FLORIDA
AS FLOW AROUND A SURFACE HIGH PRESSURE IN THE ATLANTIC MAY FUNNEL SUBTROPICAL
MOISTURE INTO THE AREA. AN ACTIVE PATTERN IS ALSO FAVORED FOR MOST OF ALASKA AS
CYCLONIC FLOW IS FORECAST TO DOMINATE MUCH OF THE STATE. ABOVE NORMAL
PRECIPITATION IS ALSO FAVORED FOR HAWAII, DUE TO PREDICTED CYCLONIC FLOW ACROSS
THE REGION.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 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 30% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT ON AN AMPLIFIED PATTERN EARLY IN THE PERIOD.
8-14 DAY OUTLOOK FOR NOV 19 - 25 2024
DURING THE WEEK-2 PERIOD, THE AMPLITUDE OF THE MEAN 500-HPA PATTERN IS FORECAST
TO BE SIGNIFICANTLY REDUCED RELATIVE TO THE 6-10 DAY PERIOD, CHARACTERISTIC OF
A TRANSITIONAL PATTERN. TROUGHING FORECAST OVER THE SOUTHWESTERN CONUS IS
PREDICTED TO QUICKLY PROGRESS ACROSS THE LOWER 48 WITH SOME SOLUTIONS (NOTABLY
THE GEFS) TRANSITIONING THE TROUGH ALL THE WAY TO THE EAST COAST BY DAY 10.
HOWEVER, THERE ARE SIGNIFICANT DIFFERENCES IN THE SPEED OF THIS PROGRESSION AND
THE AMPLITUDE OF THIS TROUGH AS IT MOVES EASTWARD. BOTH THE EUROPEAN AND
CANADIAN ENSEMBLE MEANS PREDICT A SLOWER PROGRESSION OF THE TROUGH AND
SIGNIFICANT DE-AMPLIFICATION RELATIVE TO THE GEFS. IN THE WAKE OF THIS TROUGH,
MOST SOLUTIONS FORECAST HEIGHTS TO RISE ACROSS THE WEST BY THE END OF NEXT
WEEK. HOWEVER, AGAIN, THERE IS MUCH UNCERTAINTY IN THIS POTENTIAL DEVELOPMENT
AS MOST MODELS PREDICT THIS RIDGE AS BEING A TRANSIENT FEATURE WITH SIGNIFICANT
WEAKENING BY THE END OF WEEK-2. ALASKA IS FORECAST TO UNDERGO A MAJOR
TRANSITION AS WELL. THE PERIOD BEGINS WITH CYCLONIC FLOW ACROSS MUCH OF THE
STATE. HOWEVER, AS TIME PROGRESSES SIGNIFICANT HEIGHT RISES ARE FORECAST BY ALL
ENSEMBLE MEANS WITH ABOVE NORMAL HEIGHTS FORECAST ACROSS THE STATE BY THE TIME
WE GET TO THE END OF NEXT WEEK. THE OFFICIAL MANUAL HEIGHT BLEND FOR THE WEEK-2
FEATURES ABOVE NORMAL HEIGHTS ACROSS ALASKA AND THE NORTHWESTERN CONUS WITH
CYCLONIC FLOW FORECAST FARTHER TO THE EAST OVER THE PLAINS AND MISSISSIPPI
VALLEY.
DUE TO THE PREDICTED TRANSITIONAL PATTERN, THERE IS A NOTICEABLE EASTWARD SHIFT
TO THE TEMPERATURE PATTERN ACROSS MOST OF THE FORECAST DOMAIN. AS A TROUGH IS
PREDICTED TO PROGRESS ACROSS THE LOWER 48, THE AREA OF PREDICTED ENHANCED BELOW
NORMAL TEMPERATURE PROBABILITIES HAS SHIFTED EASTWARD ACROSS THE WEST-CENTRAL
CONUS. HOWEVER, BELOW NORMAL TEMPERATURES MAY BE SLOW TO RECEDE IN AREAS
AFFECTED BY RECENT SNOW COVER. FARTHER DOWNSTREAM, THE AREA OF ELEVATED ABOVE
NORMAL TEMPERATURE PROBABILITIES ACROSS THE EASTERN CONUS IS REDUCED AND IS
MOSTLY CONFINED TO AREAS EAST OF THE MISSISSIPPI WITH AN EXTENSION WESTWARD
ACROSS PARTS OF THE NORTHERN PLAINS. A DRAMATIC PATTERN SHIFT IS ANTICIPATED
ACROSS ALASKA, WITH BELOW NORMAL TEMPERATURES FAVORED EARLY IN THE PERIOD AND
ABOVE NORMAL TEMPERATURES FAVORED LATER. AS A RESULT, ELEVATED ODDS OF NEAR
NORMAL TEMPERATURES DOMINATE THE STATE IN THE MEAN. SIMILAR TO THE 6-10 DAY
PERIOD, PROBABILITIES OF ABOVE NORMAL TEMPERATURES HAVE BEEN REDUCED FOR
HAWAII, CONSISTENT WITH THE CONSOLIDATION OF CALIBRATED EUROPEAN AND GEFS
INPUT.
WITH CYCLONIC FLOW PROGRESSING EASTWARD ACROSS THE CONUS, AREAS OF ENHANCED
ABOVE NORMAL PRECIPITATION PROBABILITIES ARE GENERALLY FOCUSED EAST OF THE
ROCKIES. THE AXIS OF GREATEST ABOVE NORMAL PRECIPITATION PROBABILITIES IS
SHIFTED EASTWARD AND EXTENDS FROM FLORIDA TO THE EASTERN GREAT LAKES.
PROBABILITIES OF ABOVE NORMAL PRECIPITATION ACROSS THIS REGION GENERALLY EXCEED
40 PERCENT. HOWEVER, GREATER THAN 50 PERCENT PROBABILITIES OF ABOVE NORMAL
PRECIPITATION IS INDICATED FOR PART OF FLORIDA DUE TO POTENTIAL ADVECTION OF
SUBTROPICAL MOISTURE. AN ACTIVE PATTERN IS FORECAST TO CONTINUE ACROSS ALASKA
IN THE PREDICTED TRANSITIONAL PATTERN WITH ABOVE NORMAL PRECIPITATION FAVORED
ACROSS THE STATE. PERSISTENT CYCLONIC FLOW ALSO INCREASES PROBABILITIES OF
ABOVE NORMAL PRECIPITATION ACROSS HAWAII.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 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 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
MODEL DISAGREEMENTS ON THE EVOLUTION OF A PREDICTED TRANSITIONAL PATTERN ACROSS
MUCH OF THE FORECAST DOMAIN.
FORECASTER: SCOTT H
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:
19981025 - 19751104 - 19831030 - 20001022 - 19771024
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:
20001021 - 19751103 - 19981025 - 19531115 - 20081021
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 17 - 21 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 A
W MONTANA B N E MONTANA N 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 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 N
VERMONT A N NEW HAMP A B MAINE A B
MASS A B CONN A N RHODE IS A B
PENN A A NEW JERSEY A N W VIRGINIA A A
MARYLAND A N DELAWARE A N VIRGINIA A A
N CAROLINA A N S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN B N AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 19 - 25 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N B OREGON N B NRN CALIF N N
SRN CALIF B B IDAHO B B NEVADA B N
W MONTANA B B E MONTANA N B WYOMING B N
UTAH B N ARIZONA B B COLORADO B A
NEW MEXICO B N N DAKOTA A N S DAKOTA N A
NEBRASKA N A KANSAS N A OKLAHOMA N A
N TEXAS N N S TEXAS N N W TEXAS B N
MINNESOTA A A IOWA N A MISSOURI N A
ARKANSAS N A LOUISIANA N 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 A
AK ALEUTIAN B A AK WESTERN N A AK INT BSN N A
AK S INT N A AK SO COAST N 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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