977  
FXUS06 KWBC 142010  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST THU NOVEMBER 14 2024  
 
6-10 DAY OUTLOOK FOR NOV 20 - 24 2024  
 
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON PREDICTING AN  
AMPLIFIED MEAN 500-HPA FLOW PATTERN ACROSS NORTH AMERICA AND SURROUNDING  
REGIONS. A HIGH AMPLITUDE RIDGE IS PREDICTED OVER THE ALEUTIAN ISLANDS, WHILE A  
TROUGH IS PREDICTED DOWNSTREAM OVER THE NORTHEASTERN PACIFIC OCEAN IN 6-10 DAY  
MEAN FORECASTS. AS THE TROUGH PROGRESSES EASTWARD OVER THE PACIFIC TOWARDS THE  
WEST COAST DURING THE PERIOD, A SECOND TROUGH IS PREDICTED TO MOVE ACROSS THE  
EASTERN CONTIGUOUS U.S. (CONUS). THE GEFS MODEL PROGRESSES THE PATTERN MORE  
RAPIDLY EASTWARD THAN THE ECMWF MODEL, SHIFTING 500-HPA HEIGHT ANOMALIES  
FURTHER EAST IN THE GEFS RELATIVE TO THE ECMWF FORECAST. A RIDGE AND ASSOCIATED  
POSITIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED OVER THE NORTHWESTERN CONUS FOR  
THE 6-10 DAY PERIOD, WITH PRIMARILY ANOMALOUS NORTHERLY FLOW INTO THE INTERIOR  
WEST.  
 
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR NORTHWESTERN MAINLAND ALASKA,  
CONSISTENT WITH POSITIVE 500-HPA HEIGHT ANOMALIES AND DECADAL TEMPERATURE  
TRENDS, WHILE NEAR NORMAL IS FAVORED OVER THE REMAINDER OF THE STATE, WHERE  
TEMPERATURE FORECAST TOOLS ARE INCONSISTENT. ABOVE NORMAL TEMPERATURES ARE  
FAVORED ALONG THE WEST COAST OF THE CONUS UNDER ANOMALOUS SOUTHERLY FLOW,  
CONSISTENT WITH THE CONSOLIDATION OF GEFS AND ECMWF TEMPERATURE FORECASTS.  
BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE INTERIOR WEST AND MUCH OF THE  
SOUTHERN CONUS, UNDER PRIMARILY NORTHERLY MID-LEVEL FLOW ASSOCIATED WITH A  
RIDGE TO THE NORTHWEST AND UNDER A TROUGH AND ASSOCIATED NEGATIVE 500-HPA  
HEIGHT ANOMALIES TO THE EAST. ABOVE NORMAL MEAN TEMPERATURES ARE FAVORED FOR  
THE GREAT LAKES REGION, MID-ATLANTIC AND NORTHEAST IN THE 6-10 DAY PERIOD, WITH  
WARMER 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. NEAR TO BELOW NORMAL PRECIPITATION IS  
FAVORED FOR MOST OF THE WESTERN CONUS, UNDER A PREDICTED RIDGE, AND FOR THE  
SOUTH-CENTRAL CONUS UNDER ANOMALOUS NORTHERLY FLOW. ABOVE NORMAL PRECIPITATION  
IS FAVORED FOR PARTS OF THE NORTHERN PLAINS, THE MIDWEST, AND THE EAST, WITH A  
TROUGH PREDICTED TO PROGRESS ACROSS 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 35% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 45% 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: ABOUT AVERAGE, 3 OUT OF 5, DUE TO  
GENERAL AGREEMENT ON THE OVERALL CIRCULATION FORECAST, OFFSET BY A CHANGING  
PATTERN AND DIFFERENCES AMONG THE MODEL TEMPERATURE AND PRECIPITATION TOOLS.  
 
8-14 DAY OUTLOOK FOR NOV 22 - 28 2024  
 
THE CHANGING 500-HPA HEIGHT PATTERN FORECAST CONTINUES INTO THE WEEK-2 PERIOD,  
WITH INCREASING DIFFERENCES BETWEEN MODELS AND DEAMPLIFICATION OF MOST  
ANOMALIES. THE GEFS CONTINUES TO BE MORE PROGRESSIVE WITH AN EASTWARD SHIFT IN  
THE LARGE-SCALE WAVE PATTERN RELATIVE TO THE ECMWF. THE ECMWF FORECAST WAS  
AGAIN GIVEN GREATER WEIGHT THAN OTHER MODELS, DUE TO RECENT SKILL. THE MANUAL  
500-HPA HEIGHT BLEND PREDICTS POSITIVE 500-HPA HEIGHT ANOMALIES ACROSS ALASKA  
AND A RIDGE CENTERED OVER THE ALEUTIANS. A PREDICTED TROUGH OVER THE  
NORTHEASTERN PACIFIC APPROACHES THE WEST COAST OF THE CONUS IN WEEK 2. THE  
MANUAL BLEND PREDICTS MEAN POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE WESTERN  
CONUS AND NEGATIVE 500-HPA HEIGHT ANOMALIES OVER MOST OF THE EASTERN CONUS,  
ASSOCIATED WITH AN AMPLIFIED TROUGH EARLY IN THE PERIOD THAT DEAMPLIFIES OVER  
TIME.  
 
ABOVE NORMAL TEMPERATURES ARE SLIGHTLY FAVORED FOR CENTRAL AND NORTHERN ALASKA  
IN WEEK 2, UNDER POSITIVE MID-LEVEL HEIGHT ANOMALIES. ABOVE NORMAL TEMPERATURES  
ARE SLIGHTLY FAVORED FOR THE WEST, CONSISTENT WITH REFORECAST-CALIBRATED GEFS  
AND ECMWF FORECASTS. BELOW NORMAL TEMPERATURES ARE FAVORED FROM THE SOUTHERN  
AND CENTRAL PLAINS INTO THE OHIO VALLEY AND SOUTHEAST, UNDER A PREDICTED MEAN  
TROUGH. ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR THE NORTHERN GREAT  
LAKES REGION AND PARTS OF THE NORTHEAST, SUPPORTED BY MOST DYNAMICAL MODEL  
TEMPERATURES FORECASTS. NEAR NORMAL TEMPERATURES ARE FAVORED FOR HAWAII WHERE  
TEMPERATURE TOOLS ARE INCONSISTENT.  
 
ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF MAINLAND ALASKA,  
CONSISTENT WITH MOST DYNAMICAL MODEL FORECASTS. WITH A PREDICTED TROUGH EXITING  
THE EASTERN CONUS AND WEAKER MID-LEVEL HEIGHT ANOMALIES, AREAS OF SLIGHTLY  
ENHANCED PROBABILITIES OF ABOVE NORMAL PRECIPITATION ARE CONFINED TO PARTS OF  
THE NORTH-CENTRAL CONUS. NEAR NORMAL PRECIPITATION IS FAVORED FOR THE  
NORTHEAST, WHERE TOOLS ARE INCONSISTENT. ABOVE NORMAL PRECIPITATION IS ALSO  
FAVORED FOR THE SOUTHERN FLORIDA PENINSULA, WHERE PRECIPITATION TOOLS ARE  
RELATIVELY CONSISTENT. BELOW NORMAL PRECIPITATION IS FAVORED ACROSS A LARGE  
AREA OF THE SOUTHERN CONUS, UNDER A DRIER PATTERN BEHIND THE EASTWARD  
PROGRESSING TROUGH. ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR PARTS OF  
CALIFORNIA AS A TROUGH IS PREDICTED TO APPROACH THE COAST DURING THE PERIOD.  
THE PRECIPITATION CONSOLIDATION FAVORS ABOVE NORMAL PRECIPITATION ACROSS  
HAWAII.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 45% 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: BELOW AVERAGE, 2 OUT OF 5, DUE TO  
MODEL FORECAST DIFFERENCES ON AN EVOLVING 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:  
20081102 - 20091119 - 20091108 - 19721107 - 19621127  
 
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:  
20091108 - 20051031 - 19721106 - 20081101 - 19561027  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 20 - 24 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON N B OREGON A B NRN CALIF A N  
SRN CALIF N N IDAHO B B NEVADA B B  
W MONTANA N B E MONTANA B N WYOMING B B  
UTAH B B ARIZONA B B COLORADO B B  
NEW MEXICO B B N DAKOTA N A S DAKOTA B A  
NEBRASKA B A KANSAS B N OKLAHOMA B B  
N TEXAS B B S TEXAS B B W TEXAS B B  
MINNESOTA A A IOWA B A MISSOURI B N  
ARKANSAS B B LOUISIANA B B WISCONSIN A A  
ILLINOIS B A MISSISSIPPI B B MICHIGAN A A  
INDIANA N A OHIO A A KENTUCKY B A  
TENNESSEE B N ALABAMA B N 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 N A GEORGIA B A  
FL PNHDL B A FL PENIN B A AK N SLOPE A A  
AK ALEUTIAN N B AK WESTERN A A AK INT BSN N A  
AK S INT N N AK SO COAST N B AK PNHDL N B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 22 - 28 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A N OREGON A N NRN CALIF A A  
SRN CALIF N N IDAHO A N NEVADA A N  
W MONTANA A N E MONTANA N A WYOMING N N  
UTAH A B ARIZONA A B COLORADO N B  
NEW MEXICO N B N DAKOTA N A S DAKOTA B N  
NEBRASKA B N KANSAS B B OKLAHOMA B B  
N TEXAS B B S TEXAS B B W TEXAS B B  
MINNESOTA A N IOWA B N MISSOURI B B  
ARKANSAS B B LOUISIANA B B WISCONSIN N N  
ILLINOIS B B MISSISSIPPI B B MICHIGAN A N  
INDIANA B B OHIO B N KENTUCKY B B  
TENNESSEE B B ALABAMA B B NEW YORK A N  
VERMONT A N NEW HAMP A N MAINE A N  
MASS A N CONN A N RHODE IS A N  
PENN N N NEW JERSEY N N W VIRGINIA B B  
MARYLAND N N DELAWARE N B VIRGINIA B B  
N CAROLINA B B S CAROLINA B B GEORGIA B B  
FL PNHDL B B FL PENIN B A AK N SLOPE A A  
AK ALEUTIAN N B AK WESTERN N N AK INT BSN N A  
AK S INT N N AK SO COAST N N AK PNHDL N 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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