393  
FXUS06 KWBC 021901  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT THU NOVEMBER 02 2017  
 
6-10 DAY OUTLOOK FOR NOV 08 - 12 2017  
 
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT IN THEIR PREDICTION OF  
THE FLOW PATTERN OVER MUCH OF THE FORECAST DOMAIN. A STRONG RIDGE IS FORECAST  
OVER WESTERN MAINLAND ALASKA, WHILE A TROUGH IS EXPECTED NEAR THE ALASKA  
PANHANDLE. A DEEP TROUGH IS EXPECTED NORTH OF HUDSON BAY EXTENDING  
SOUTHEASTWARD OVER NORTHEASTERN NORTH AMERICA, WHILE RIDGES ARE ANTICIPATED  
OVER THE CENTRAL ATLANTIC AND CENTERED OVER MEXICO. FAST ZONAL FLOW IS FORECAST  
FOR MUCH OF THE CONUS.  
 
THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE LOW TO MODERATE SPREAD FOR MOST OF THE  
CONUS, WITH MODERATE TO LARGE SPREAD DEPICTED FOR THE EASTERN PACIFIC AND  
ALASKA. THE PNA INDEX, WHICH RECENTLY HAS BEEN NEGATIVE, IS FORECAST TO REMAIN  
NEGATIVE THROUGH DAY 14, WHILE THE AO INDEX WHICH HAS RECENTLY BEEN POSITIVE IS  
ANTICIPATED TO REMAIN POSITIVE THROUGH DAY 10, AND BE NEAR ZERO AT DAY 14.  
TODAYS BLENDED HEIGHT CHART INDICATES NEAR TO BELOW NORMAL HEIGHTS FOR THE  
NORTHWEST CONUS AND ACROSS MUCH OF THE EASTERN PORTIONS OF THE CONUS (EXCEPT  
FLORIDA), WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE ANTICIPATED FOR THE REMAINDER  
OF THE FORECAST DOMAIN. POSITIVE HEIGHT ANOMALIES EXCEEDING 250 METERS ARE  
FORECAST OVER THE ALEUTIANS. TELECONNECTIONS ON THIS AREA OF POSITIVE HEIGHT  
ANOMALIES YIELDS A HEIGHT PATTERN VERY SIMILAR TO THAT FORECAST BY THE  
DYNAMICAL MODELS.  
 
ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES FOR MUCH OF THE  
SOUTHERN AND INTERIOR WESTERN CONUS, WHILE NEAR TO BELOW NORMAL HEIGHTS FAVOR  
NEAR TO BELOW NORMAL TEMPERATURES FOR THE NORTHERN TIER OF THE CONUS, THE OHIO  
VALLEY, THE NORTHWESTERN PORTION OF THE U.S., AND PARTS OF NORTHERN CALIFORNIA.  
ANOMALOUS NORTHWESTERLY FLOW ENHANCES PROBABILITIES FOR BELOW NORMAL  
TEMPERATURES FOR PARTS OF THE CENTRAL CONUS. ABOVE NORMAL HEIGHTS FAVOR ABOVE  
NORMAL TEMPERATURES FOR NORTHERN ALASKA AND THE WESTERN ALEUTIANS, WHILE  
ANOMALOUS NORTHEASTERLY FLOW TILTS THE ODDS TO BELOW NORMAL TEMPERATURES FOR  
SOUTHEASTERN MAINLAND ALASKA AND THE ALASKA PANHANDLE.  
 
CYCLONIC FLOW AND/OR BELOW NORMAL HEIGHTS FAVOR ABOVE NORMAL PRECIPITATION FOR  
PARTS OF THE NORTHEAST, MID-ATLANTIC, OHIO AND TENNESSEE VALLEYS, APPALACHIANS,  
AND NORTHWEST CONUS. ABOVE NORMAL HEIGHTS TILT THE ODDS TO BELOW NORMAL  
PRECIPITATION ACROSS MUCH OF THE SOUTHERN AND WEST-CENTRAL CONUS.  
BELOW NORMAL PRECIPITATION IS ALSO FAVORED FOR MUCH OF SOUTHERN ALASKA DUE TO  
EXPECTED OFFSHORE FLOW. HOWEVER, ABOVE NORMAL PRECIPITATION PROBABILITIES ARE  
ENHANCED FOR NORTHERN MAINLAND ALASKA UNDERNEATH WESTERLY LOW LEVEL FLOW.  
 
TODAY'S OFFICIAL 500-HPA 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, 35%  
OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF TODAY'S  
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 15% OF TODAY'S 0Z CANADIAN ENSEMBLE  
MEAN CENTERED ON DAY 8, AND 5% OF YESTERDAY'S 12Z CANADIAN ENSEMBLE MEAN  
CENTERED ON DAY 7  
 
 
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 10 - 16 2017  
 
DURING THE WEEK-2 PERIOD, A SLIGHT PROGRESSION OF THE TROUGH PREDICTED OVER  
NORTHEAST NORTH AMERICA AND A SLIGHT SUPPRESSION OF THE RIDGE NEAR MEXICO ARE  
INDICATED. HEIGHTS ARE EXPECTED TO BE NEAR TO BELOW NORMAL FOR THE NORTHWESTERN  
AND NORTHEASTERN CONUS, FLORIDA, AND THE ALASKA PANHANDLE, AND NEAR TO ABOVE  
NORMAL OVER THE REMAINDER OF THE FORECAST DOMAIN. THE ENSEMBLE SPAGHETTI  
DIAGRAMS INDICATE MODERATE SPREAD FOR THE EASTERN CONUS, WITH MODERATE TO LARGE  
SPREAD DEPICTED FOR THE WESTERN CONUS, EASTERN PACIFIC, AND ALASKA.  
 
NEAR TO BELOW NORMAL HEIGHTS AND/OR COLD SURFACE HIGH PRESSURE FAVOR NEAR TO  
BELOW NORMAL TEMPERATURES FOR PARTS OF THE NORTHERN TIER OF THE CONUS AND  
EASTERN SECTIONS OF THE NORTHEAST AND MID-ATLANTIC, AND THE ALASKA PANHANDLE.  
NEAR TO ABOVE NORMAL HEIGHTS TILT THE ODDS TO NEAR TO ABOVE NORMAL TEMPERATURES  
FOR THE REMAINDER OF THE CONUS, NORTHERN ALASKA, AND THE WESTERN ALEUTIANS.  
 
CYCLONIC FLOW AND THE POTENTIAL FOR LAKE EFFECT PRECIPITATION ENHANCE  
PROBABILITIES FOR ABOVE NORMAL PRECIPITATION FOR PARTS OF THE GREAT LAKES.  
ABOVE NORMAL HEIGHTS TILT THE ODDS TO BELOW NORMAL PRECIPITATION FOR PARTS OF  
THE GULF COAST, THE SOUTHEAST CONUS, THE HIGH PLAINS, AND THE SOUTHWEST CONUS.  
THE TROUGH FORECAST NEAR THE ALASKA PANHANDLE FAVORS ABOVE NORMAL PRECIPITATION  
FOR THE NORTHWESTERN CONUS AND EXTREME NORTHERN SECTIONS OF THE NORTHERN PLAINS  
AND UPPER MISSISSIPPI VALLEY. WESTERLY SURFACE FLOW ENHANCES PROBABILITIES FOR  
ABOVE NORMAL PRECIPITATION FOR NORTHERN ALASKA WHILE ABOVE NORMAL HEIGHTS TILT  
THE ODDS TO BELOW NORMAL PRECIPITATION FOR SOUTHERN MAINLAND ALASKA, THE  
ALEUTIANS, AND THE ALASKA PANHANDLE.  
 
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5% OF TODAY'S 0Z GFS ENSEMBLE  
MEAN CENTERED ON DAY 11, 30% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY  
11, 25% OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 5% OF TODAY'S  
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 11, AND 10% OF YESTERDAY'S 12Z EUROPEAN ENSEMBLE MEAN CENTERED  
ON DAY 10  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE  
TO FAIR AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS ON THE 500-HPA PATTERN.  
 
FORECASTER: RANDY S  
 
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:  
19811023 - 20031029 - 19911020 - 19591110 - 19861111  
 
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:  
20031029 - 19811022 - 19861110 - 19911019 - 19951105  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 08 - 12 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A NRN CALIF N A  
SRN CALIF A N IDAHO N A NEVADA A N  
W MONTANA B A E MONTANA B N WYOMING A B  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B B S DAKOTA N B  
NEBRASKA N B KANSAS B B OKLAHOMA B B  
N TEXAS N B S TEXAS A B W TEXAS A B  
MINNESOTA B B IOWA B B MISSOURI B B  
ARKANSAS B B LOUISIANA A B WISCONSIN B B  
ILLINOIS B N MISSISSIPPI N B MICHIGAN B N  
INDIANA B N OHIO B A KENTUCKY B A  
TENNESSEE B A ALABAMA N N NEW YORK B A  
VERMONT B A NEW HAMP B A MAINE B A  
MASS N A CONN N A RHODE IS N A  
PENN B A NEW JERSEY N A W VIRGINIA B A  
MARYLAND B A DELAWARE N A VIRGINIA B A  
N CAROLINA N A S CAROLINA N A GEORGIA N N  
FL PNHDL A B FL PENIN A B AK N SLOPE A A  
AK ALEUTIAN N B AK WESTERN A B AK INT BSN N N  
AK S INT B B AK SO COAST B B AK PNHDL B B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR NOV 10 - 16 2017  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON N A NRN CALIF A A  
SRN CALIF A B IDAHO A A NEVADA A N  
W MONTANA B A E MONTANA N A WYOMING A N  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B 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 B A IOWA A B MISSOURI A B  
ARKANSAS A B LOUISIANA A B WISCONSIN N A  
ILLINOIS A B MISSISSIPPI A B MICHIGAN N A  
INDIANA A B OHIO N N KENTUCKY A B  
TENNESSEE A B ALABAMA A B NEW YORK B N  
VERMONT B B NEW HAMP B B MAINE B B  
MASS B B CONN B B RHODE IS B B  
PENN B B NEW JERSEY B B W VIRGINIA N B  
MARYLAND B B DELAWARE B B VIRGINIA B B  
N CAROLINA B B S CAROLINA N B GEORGIA N B  
FL PNHDL N B FL PENIN N B AK N SLOPE A A  
AK ALEUTIAN N B AK WESTERN A B AK INT BSN N N  
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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