705  
FXUS06 KWBC 082038  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST MON JANUARY 08 2018  
 
6-10 DAY OUTLOOK FOR JAN 14 - 18 2018  
 
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA  
FLOW PATTERN OVER THE FORECAST DOMAIN. THE HIGHLY AMPLIFIED A TROUGH IS  
EXPECTED OVER THE BERING SEA AND GULF OF ALASKA. A RIDGE IS PREDICTED OVER  
WESTERN NORTH AMERICA. DOWNSTREAM, A TROUGH IS LIKELY TO OVER THE EASTERN  
CONUS. ABOVE NORMAL 500-HPA HEIGHTS ARE PREDICTED OVER ALASKA AND THE WESTERN  
CONUS, WHILE BELOW NORMAL 500-HPA HEIGHTS ARE FORECAST FOR THE CENTRAL AND  
EASTERN CONUS, EXCEPT FOR NORTHEAST.  
 
ABOVE NORMAL HEIGHTS FORECAST OVER THE WESTERN CONUS AND ALASKA WITH  
SOUTHEASTERLY SURFACE FLOW OVER THE NORTHWEST CONUS LEAD TO INCREASED CHANCES  
OF ABOVE NORMAL TEMPERATURES THERE. BELOW NORMAL TEMPERATURES ARE LIKELY FOR  
THE EASTERN CONUS, UNDERNEATH THE PREDICTED TROUGH.  
 
EAST OF THE UPPER-LEVEL TROUGH PREDICTED OVER THE ALEUTIANS, SOUTHEASTERLY FLOW  
AT THE SURFACE INCREASES CHANCES OF ABOVE NORMAL PRECIPITATION OVER SOUTHERN  
ALASKA, THE ALEUTIANS AND THE ALASKA PANHANDLE. ABOVE NORMAL PRECIPITATION IS  
ALSO FAVORED FOR THE NORTHWESTERN CONUS, DUE TO THE FRONTAL ACTIVITY AND THE  
SOUTHWESTERLY SURFACE FLOW. BELOW NORMAL PRECIPITATION IS LIKELY FOR THE REST  
OF THE CONUS, WITH HIGH PROBABILITIES OF BELOW NORMAL PRECIPITATION ACROSS THE  
SOUTHERN CONUS, SUPPORTED BY THE STRONG ANOMALOUS RIDGE FORECAST ALONG THE  
WESTERN CONUS AND THE NORTHEASTERLY SURFACE FLOW OVER THE SOUTHEASTERN CONUS.  
THAT PATTERN IS CONSISTENT WITH PREDICTIONS FROM THE ECMWF AND GEFS CALIBRATED  
REFORECAST TOOLS.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT 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 TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 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  
REASONABLY GOOD AGREEMENT AMONG MOST MODELS AND TOOLS.  
 
8-14 DAY OUTLOOK FOR JAN 16 - 22 2018  
 
DURING WEEK-2, MODELS ARE IN FAIRLY GOOD AGREEMENT, AND THEY PREDICT A SIMILAR  
CIRCULATION PATTERN TO THAT EXPECTED DURING THE 6-10 DAY PERIOD. THE TROUGH  
PREDICTED OVER THE EAST-CENTRAL CONUS IS FORECAST TO DEAMPLIFY DURING WEEK-2,  
WITH RAPIDLY RISING MID-TROPOSPHERIC HEIGHTS AND POSITIVE ANOMALOUS HEIGHTS  
OVER THIS REGION.  
 
ABOVE NORMAL TEMPERATURES ARE STILL FAVORED FOR MOST OF MAINLAND ALASKA AND THE  
ALEUTIANS. WARMER THAN NORMAL CONDITIONS ARE ANTICIPATED TO SPREAD RAPIDLY  
EASTWARD ACROSS MOST OF THE CONUS DURING THE WEEK-2 PERIOD, WITH THE EXCEPTION  
OF THE EASTERN GULF COAST STATES AND THE SOUTHERN ATLANTIC COAST STATES  
ASSOCIATED WITH RAPIDLY RISING HEIGHTS ACROSS THE CENTRAL AND EAST-CENTRAL  
CONUS. THE ECMWF ENSEMBLE MEAN CALIBRATED REFORECAST TEMPERATURE TOOL IS FASTER  
THAN ITS GEFS COUNTERPART TO WARM UP THE EASTERN CONUS.  
 
FOR THE WEEK-2 PRECIPITATION OUTLOOK, BELOW NORMAL PRECIPITATION IS PREDICTED  
OVER EASTERN ALASKA AND THE ALASKA PANHANDLE AS THE ANOMALOUS TROUGH PROGRESSES  
TO THE WESTERN COAST. TROUGHING OVER THE WEST COAST AND EASTERN CONUS IMPLIES  
STORM ACTIVITY FROM THE NORTHWEST TO THE GREAT LAKES AND THE OHIO AND THE  
TENNESSEE VALLEYS, WHERE NEAR TO ABOVE NORMAL PRECIPITATION IS FAVORED. BELOW  
NORMAL PRECIPITATION IS LIKELY FOR MOST OF THE SOUTHERN CONUS, SUPPORTED BY  
CONSISTENT WITH PREDICTIONS FROM THE ECMWF AND GEFS REFORECAST TOOLS.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND 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 TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 20% 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: NEAR AVERAGE, 3 OUT OF 5, DUE TO  
REASONABLE OVERALL MODEL AND TOOL AGREEMENT, BUT OFFSET BY THE UNCERTAINTY  
INHERENT IN A TRANSITIONING CIRCULATION PATTERN.  
 
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  
JANUARY 18.  
 
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:  
19570101 - 19851229 - 20090120 - 19771227 - 20060107  
 
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:  
19561231 - 19851229 - 19890102 - 19850120 - 19991227  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR JAN 14 - 18 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A N IDAHO A A NEVADA A N  
W MONTANA A A E MONTANA A A WYOMING A N  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA N N S DAKOTA N N  
NEBRASKA N N KANSAS N N OKLAHOMA B B  
N TEXAS B B S TEXAS B B W TEXAS A B  
MINNESOTA B B IOWA B B MISSOURI B B  
ARKANSAS B B LOUISIANA B B WISCONSIN B B  
ILLINOIS B B MISSISSIPPI B B MICHIGAN B B  
INDIANA B B OHIO B B KENTUCKY B B  
TENNESSEE B B ALABAMA B B NEW YORK B B  
VERMONT B N NEW HAMP B N MAINE B N  
MASS B N CONN B N RHODE IS B N  
PENN B B NEW JERSEY B N W VIRGINIA B B  
MARYLAND B B DELAWARE B B VIRGINIA B B  
N CAROLINA B B S CAROLINA B B GEORGIA B B  
FL PNHDL B B FL PENIN B B AK N SLOPE A N  
AK ALEUTIAN A A AK WESTERN A N AK INT BSN A N  
AK S INT A A AK SO COAST A A AK PNHDL A A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR JAN 16 - 22 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A A IDAHO A A NEVADA A A  
W MONTANA A A E MONTANA N A WYOMING A A  
UTAH A A ARIZONA A B COLORADO A A  
NEW MEXICO A B N DAKOTA N A S DAKOTA A A  
NEBRASKA A A KANSAS A A OKLAHOMA A A  
N TEXAS A N S TEXAS A B W TEXAS A B  
MINNESOTA A 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 A 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 N W VIRGINIA A N  
MARYLAND A N DELAWARE A B VIRGINIA A N  
N CAROLINA N B S CAROLINA N B GEORGIA N B  
FL PNHDL N B FL PENIN N B AK N SLOPE A N  
AK ALEUTIAN A A AK WESTERN A A AK INT BSN A B  
AK S INT A B AK SO COAST N 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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