773  
FXUS06 KWBC 062039  
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 06 2017  
 
6-10 DAY OUTLOOK FOR NOV 12 - 16 2017  
 
TODAY'S DYNAMICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THEIR 500-HPA  
CIRCULATION FORECASTS FOR THE 6-10 DAY PERIOD OVER THE NORTH AMERICAN REGION. A  
STRONG RIDGE IS FORECAST OVER THE ALEUTIANS AND BERING SEA, WHILE A TROUGH IS  
PREDICTED IN THE NORTH PACIFIC NEAR THE ALASKA PANHANDLE AND PACIFIC NORTHWEST.  
ABOVE NORMAL 500-HPA HEIGHTS ARE PREDICTED OVER THE SOUTHWEST, THE CENTRAL  
CONUS, AND THE NORTHEAST. ENSEMBLE SPREAD IS RELATIVELY LOW INDICATING GOOD  
AGREEMENT AMONG MEMBERS ON THE CIRCULATION PATTERN.  
 
ABOVE NORMAL TEMPERATURES ARE MOST LIKELY FOR WESTERN ALASKA WITH POSITIVE  
500-HPA HEIGHT ANOMALIES UNDER THE PREDICTED RIDGE. BELOW NORMAL TEMPERATURES  
ARE LIKELY FOR SOUTHEASTERN ALASKA, INCLUDING THE ALASKA PANHANDLE, AND PARTS  
OF THE PACIFIC NORTHWEST UNDER BELOW NORMAL 500-HPA HEIGHTS ASSOCIATED WITH A  
PREDICTED TROUGH. ABOVE NORMAL TEMPERATURES ARE MOST LIKELY FOR MUCH OF THE  
REMAINING AREAS OF THE CONUS UNDER PREDICTED ABOVE NORMAL 500-HPA HEIGHTS. NEAR  
NORMAL TEMPERATURES ARE MORE LIKELY FOR PARTS OF THE NORTHEAST CONUS WITH  
PREDICTED TROUGHING AND POTENTIAL BELOW NORMAL TEMPERATURES EARLY IN THE 6-10  
DAY PERIOD.  
 
ABOVE NORMAL PRECIPITATION IS LIKELY FOR NORTHERN ALASKA AND THE ALASKA  
INTERIOR, WITH PREDICTED NORTHERLY MID-LEVEL FLOW, WHILE BELOW NORMAL  
PRECIPITATION IS MORE LIKELY FOR THE SOUTHERN COAST OF ALASKA. ABOVE NORMAL  
PRECIPITATION IS MOST LIKELY FOR NORTHERN CALIFORNIA AND THE PACIFIC NORTHWEST  
REGION AHEAD OF THE PREDICTED TROUGH OVER THE NORTH PACIFIC. THE PROBABILITIES  
OF ABOVE NORMAL PRECIPITATION ARE SLIGHTLY ELEVATED FOR THE 6-10 DAY PERIOD  
AVERAGE OVER THE NORTHEASTERN AREAS OF THE CONUS, INCLUDING THE OHIO VALLEY,  
MID-ATLANTIC, AND NEW ENGLAND, WITH A TROUGH AND PRECIPITATION FORECAST EARLY  
IN THE PERIOD.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 10% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 25% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED  
ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 25%  
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  
GOOD MODEL AGREEMENT ON THE EXPECTED CIRCULATION PATTERN, LOW ENSEMBLE MEMBER  
SPREAD, AND FAIRLY GOOD AGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION TOOLS.  
 
8-14 DAY OUTLOOK FOR NOV 14 - 20 2017  
 
THE OVERALL 500-HPA CIRCULATION PATTERN PREDICTED FOR THE WEEK 2 PERIOD CHANGES  
LITTLE FROM THE 6-10 DAY PERIOD FORECAST, HOWEVER, ENSEMBLE SPREAD INCREASES  
SUBSTANTIALLY, INDICATING GREATER FORECAST UNCERTAINTY. SOME RETROGRESSION OF A  
PREDICTED TROUGH OVER SOUTHEASTERN ALASKA IS INDICATED BETWEEN 6-10 DAY AND  
WEEK 2 PERIODS BY ALL ENSEMBLE MEAN SOLUTIONS. MEAN 500-HPA HEIGHT ANOMALIES  
ARE SOMEWHAT WEAKER OVER THE CONUS IN THE WEEK 2 FORECASTS, RELATED TO  
INCREASING SPREAD AMONG ENSEMBLE MEMBERS.  
 
BELOW NORMAL TEMPERATURES ARE MOST LIKELY FOR A LARGER AREA OF SOUTHEASTERN  
ALASKA WITH DECREASING PREDICTED 500-HPA HEIGHTS. ABOVE NORMAL TEMPERATURES  
REMAIN MOST LIKELY FOR PARTS OF THE WESTERN ALEUTIANS, THE NORTHWEST COAST, AND  
THE NORTH SLOPE. BELOW NORMAL TEMPERATURES REMAIN MOST LIKELY FOR PARTS OF THE  
PACIFIC NORTHWEST WITH PREDICTED BELOW NORMAL 500-HPA HEIGHTS. ABOVE NORMAL  
TEMPERATURES ARE LIKELY FROM CENTRAL AND SOUTHERN CALIFORNIA, ACROSS THE  
SOUTHWEST, AND FOR THE EASTERN TWO-THIRDS OF THE CONUS, UNDER PREDICTED ABOVE  
NORMAL 500-HPA HEIGHTS AND MEAN ZONAL FLOW. THE PROBABILITIES OF ABOVE NORMAL  
TEMPERATURES HAVE INCREASED FOR THE NORTHEAST, WHERE MODEL FORECASTS INDICATE  
TROUGHING IS LESS LIKELY INTO THE WEEK 2 PERIOD.  
 
ABOVE NORMAL PRECIPITATION IS MOST LIKELY ACROSS MUCH OF THE NORTHERN TIER OF  
THE CONUS, FROM THE PACIFIC NORTHWEST TO THE GREAT LAKES REGION, WITH ZONAL  
FLOW INDICATED AHEAD OF A PREDICTED TROUGH. BELOW NORMAL PRECIPITATION IS  
INDICATED FOR MOST OF THE REMAINING AREAS OF THE CONUS, EXCEPT FOR  
CLIMATOLOGICALLY DRY AREAS OF THE SOUTHWEST WHERE NEAR NORMAL PRECIPITATION IS  
INDICATED. AREAS OF SOUTHERN ALASKA THAT ARE WEST OF THE MEAN LOCATION OF THE  
RETROGRESSING TROUGH AXIS, ARE PREDICTED TO HAVE BELOW NORMAL PRECIPITATION IN  
THE WEEK 2 PERIOD. ABOVE NORMAL PRECIPITATION IS LIKELY FOR PARTS OF THE NORTH  
SLOPE UNDER PREDICTED NORTHERLY FLOW.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 10% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 25% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED  
ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 25%  
OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE  
TO GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS ON THE 500-HPA CIRCULATION  
PATTERN DURING WEEK 2, OFFSET BY LARGE SPREAD AMONG THE ENSEMBLE MEMBERS.  
 
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 1981-2010 BASE PERIOD MEANS FOR  
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN THE CLIMATE  
OUTLOOKS.  
 
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON  
NOVEMBER 16  
 
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:  
19911022 - 20031031 - 19711102 - 19851109 - 19861115  
 
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:  
19911022 - 19851109 - 20031031 - 19711102 - 20031105  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 12 - 16 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON N A NRN CALIF N A  
SRN CALIF A B IDAHO N A NEVADA A A  
W MONTANA B A E MONTANA N B WYOMING A B  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A N N DAKOTA A B S DAKOTA A B  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA A B IOWA A B MISSOURI A B  
ARKANSAS A B LOUISIANA A B WISCONSIN A N  
ILLINOIS A N MISSISSIPPI A B MICHIGAN A N  
INDIANA A A OHIO N A KENTUCKY N N  
TENNESSEE N N ALABAMA A B NEW YORK N A  
VERMONT N A NEW HAMP N A MAINE N A  
MASS N A CONN N A RHODE IS A A  
PENN N A NEW JERSEY A A W VIRGINIA N A  
MARYLAND N A DELAWARE A A VIRGINIA N A  
N CAROLINA N N S CAROLINA N N GEORGIA A B  
FL PNHDL A B FL PENIN A N AK N SLOPE A A  
AK ALEUTIAN N B AK WESTERN A A AK INT BSN A A  
AK S INT B B AK SO COAST B B AK PNHDL B B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 14 - 20 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON N A NRN CALIF N B  
SRN CALIF A B IDAHO B A NEVADA N N  
W MONTANA B A E MONTANA N A WYOMING A B  
UTAH A B ARIZONA A N COLORADO A B  
NEW MEXICO A N N DAKOTA A A S DAKOTA A B  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A N  
MINNESOTA A A IOWA A B MISSOURI A B  
ARKANSAS A B LOUISIANA A B WISCONSIN A A  
ILLINOIS A N MISSISSIPPI A B MICHIGAN A A  
INDIANA A N OHIO A N KENTUCKY A N  
TENNESSEE A B ALABAMA A 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 A N NEW JERSEY A B W VIRGINIA A B  
MARYLAND A B DELAWARE A B VIRGINIA A B  
N CAROLINA A B S CAROLINA A B GEORGIA A B  
FL PNHDL A B FL PENIN A B AK N SLOPE A A  
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B B  
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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