360  
FXUS06 KWBC 301914  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT MON OCTOBER 30 2017  
 
6-10 DAY OUTLOOK FOR NOV 05 - 09 2017  
 
TODAY'S ENSEMBLE MEAN AND DETERMINISTIC SOLUTIONS ARE IN GOOD AGREEMENT ON  
500-HPA FLOW PATTERN PREDICTED OVER THE FORECAST DOMAIN. A RIDGE IS PREDICTED  
OVER THE EASTERN BERING SEA AND WESTERN ALASKA, WHILE AN AMPLIFIED TROUGH IS  
EXPECTED OVER THE NORTHWESTERN CONUS. DOWNSTREAM, A RIDGE IS ANTICIPATED OVER  
THE EASTERN CONUS. ENSEMBLE SPREAD IS MODERATE OVER THE MAJORITY OF THE  
FORECAST DOMAIN. TODAY'S OFFICIAL 500-HPA MANUAL HEIGHT BLEND INDICATES ABOVE  
NORMAL HEIGHTS OVER ALASKA ALONG WITH THE SOUTH-CENTRAL AND EASTERN CONUS,  
WHILE NEAR TO BELOW NORMAL HEIGHTS ARE EXPECTED OVER THE WESTERN AND  
NORTH-CENTRAL CONUS.  
 
BELOW NORMAL HEIGHTS TILT THE ODDS TO BELOW NORMAL TEMPERATURES FOR THE WESTERN  
AND THE NORTH-CENTRAL CONUS. THE RIDGE OVER THE EASTERN CONUS WITH ABOVE NORMAL  
HEIGHTS, ENHANCE PROBABILITIES OF ABOVE NORMAL TEMPERATURES FOR THE  
SOUTH-CENTRAL AND EASTERN CONUS. ABOVE NORMAL HEIGHTS AND ABOVE NORMAL SEA  
SURFACE TEMPERATURES ENHANCE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR  
ALASKA AND THE ALEUTIANS EXCEPT THE BELOW NORMAL TEMPERATURE IN THE ALASKA  
PANHANDLE.  
 
THE TROUGH FORECAST OVER THE WESTERN U.S. FAVORS ABOVE NORMAL PRECIPITATION FOR  
THE WESTERN AND NORTH-CENTRAL CONUS. ABOVE NORMAL PRECIPITATION IS ALSO FAVORED  
ACROSS THE UPPER MISSISSIPPI VALLEY, THE GREAT LAKES REGION, THE OHIO AND  
TENNESSEE VALLEYS, AND THE NORTHEAST IN GOOD AGREEMENT WITH THE GEFS AND ECMWF  
CALIBRATED REFORECAST TOOLS. NEAR TO ABOVE NORMAL HEIGHTS ENHANCE PROBABILITIES  
FOR BELOW NORMAL PRECIPITATION FOR THE SOUTHEASTERN CONUS AND SOUTHERN TEXAS.  
PROBABILITIES OF BELOW NORMAL PRECIPITATION OVER THE CENTRAL GREAT PLAINS ARE  
RELATED TO THE WESTERLY, DOWN-SLOPE FLOW. ABOVE NORMAL PRECIPITATION IS FAVORED  
IN ALASKA ASSOCIATION WITH THE STORM TRACK WITH THE NORTHWESTERLY FLOW.  
 
TODAY'S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY'S 0Z GFS ENSEMBLE MEAN  
CENTERED ON DAY 8, 20% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 20%  
OF YESTERDAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 7, 20% 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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO  
GOOD MODEL AGREEMENT ON THE EXPECTED FLOW PATTERN OVER MUCH OF THE FORECAST  
DOMAIN.  
 
8-14 DAY OUTLOOK FOR NOV 07 - 13 2017  
 
ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT TODAY FOR THE WEEK-2 PERIOD OVER  
MOST OF THE FORECAST DOMAIN. THE OVERALL CIRCULATION PATTERN IS QUITE SIMILAR  
TO THE 6-10 DAY PERIOD BUT LESS AMPLIFIED DURING WEEK-2. TODAY'S WEEK-2 BLENDED  
500-HPA HEIGHT CHART INDICATES NEAR TO ABOVE NORMAL HEIGHTS OVER THE EASTERN  
AND SOUTH-CENTRAL CONUS AND ALASKA, WHILE NEAR TO BELOW NORMAL HEIGHTS ARE  
ANTICIPATED OVER THE NORTHWESTERN CONUS.  
 
THE WEEK-2 TEMPERATURE OUTLOOK REFLECTS A STABLE PATTERN WITH SPATIAL COVERAGE  
OF FAVORED AREAS OF BELOW AND ABOVE-NORMAL TEMPERATURES QUITE SIMILAR TO DAYS  
6-10. BELOW-NORMAL TEMPERATURES ARE MOST LIKELY ACROSS THE NORTHERN ROCKIES AND  
NORTHERN GREAT PLAINS WHERE LARGE NEGATIVE TEMPERATURE ANOMALIES ARE EXPECTED.  
 
THE PRECIPITATION OUTLOOK IS FORECAST TO BE SIMILAR TO THAT OF THE 6-10 DAY  
PERIOD OVER ALASKA AND THE EASTERN CONUS. THE ONE NOTEWORTHY DIFFERENCE IN THE  
PRECIPITATION OUTLOOK FOR WEEK-2 COMPARED TO DAYS 6-10 IS NEAR TO BELOW-NORMAL  
PRECIPITATION FAVORED FOR SOUTHERN CALIFORNIA AND THE DESERT SOUTHWEST DUE TO  
THE PRECIPITATION SHIFTING EAST OF THE THESE AREAS BY DAY 8.  
 
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY'S 0Z GFS ENSEMBLE  
MEAN CENTERED ON DAY 11, 20% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY  
11, 20% OF YESTERDAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10, 20% OF  
TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF YESTERDAY'S  
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO  
GENERALLY GOOD MODEL AGREEMENT, OFFSET BY MODERATE SPREAD AMONG INDIVIDUAL  
ENSEMBLE MEMBERS WITH RESPECT TO THE PACIFIC TROUGH.  
 
FORECASTER: QIN Z  
 
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:  
19811021 - 19591110 - 19671102 - 20061010 - 19661103  
 
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:  
19591109 - 19811020 - 19671103 - 20061009 - 19661103  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 05 - 09 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A 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 N A COLORADO A B  
NEW MEXICO A N N DAKOTA B A S DAKOTA B A  
NEBRASKA N B KANSAS A A OKLAHOMA A A  
N TEXAS A A S TEXAS A B W TEXAS A A  
MINNESOTA N A IOWA A A MISSOURI A A  
ARKANSAS A A LOUISIANA A B WISCONSIN A A  
ILLINOIS A A MISSISSIPPI A B MICHIGAN A A  
INDIANA A A OHIO A A KENTUCKY A A  
TENNESSEE A N ALABAMA A B NEW YORK A A  
VERMONT A A NEW HAMP A A MAINE A A  
MASS A A CONN A A RHODE IS A N  
PENN A A NEW JERSEY A A W VIRGINIA A A  
MARYLAND A N DELAWARE A N VIRGINIA A N  
N CAROLINA A B S CAROLINA A B GEORGIA A B  
FL PNHDL A B FL PENIN A N AK N SLOPE A A  
AK ALEUTIAN A N AK WESTERN A A AK INT BSN A A  
AK S INT A A AK SO COAST A B AK PNHDL B B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 07 - 13 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A NRN CALIF B A  
SRN CALIF B N IDAHO B A NEVADA B N  
W MONTANA B A E MONTANA B A WYOMING B B  
UTAH B B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B N S DAKOTA B B  
NEBRASKA N B KANSAS A A OKLAHOMA A A  
N TEXAS A A S TEXAS A B W TEXAS A A  
MINNESOTA B A IOWA N A MISSOURI A A  
ARKANSAS A A LOUISIANA A B WISCONSIN N A  
ILLINOIS A A MISSISSIPPI A B MICHIGAN A A  
INDIANA A A OHIO A A KENTUCKY A A  
TENNESSEE A N ALABAMA A B NEW YORK A A  
VERMONT A A NEW HAMP A A MAINE A A  
MASS A N CONN A N RHODE IS A N  
PENN A A NEW JERSEY A N W VIRGINIA A A  
MARYLAND A N DELAWARE A N VIRGINIA A N  
N CAROLINA A N S CAROLINA A B GEORGIA A B  
FL PNHDL A B FL PENIN A B AK N SLOPE A A  
AK ALEUTIAN A B AK WESTERN A A AK INT BSN A A  
AK S INT A A AK SO COAST A 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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