937  
FXUS06 KWBC 062021  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST TUE MARCH 06 2018  
 
6-10 DAY OUTLOOK FOR MAR 12 - 16 2018  
 
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE EXPECTED LARGE  
SCALE 500-HPA CIRCULATION PATTERN IN THE 6-10 DAY PERIOD. A HIGH AMPLITUDE  
TROUGH IS PREDICTED OVER THE GULF OF ALASKA. DOWNSTREAM, A STRONG RIDGE IS  
PREDICTED OVER CENTRAL NORTH AMERICA WITH A TROUGH OVER THE EASTERN CONUS AND  
THE ATLANTIC COAST. BELOW NORMAL 500-HPA HEIGHTS ARE PREDICTED OVER MAINLAND  
ALASKA AND THE ALASKA PANHANDLE, THE WEST COAST OF THE CONUS, AND THE EASTERN  
CONUS. ABOVE NORMAL 500-HPA HEIGHTS ARE FORECAST FOR THE CENTRAL CONUS AND THE  
ALEUTIANS.  
 
TROUGHING IN THE GULF OF ALASKA AND THE EASTERN PACIFIC LEADS TO INCREASED  
CHANCES FOR BELOW NORMAL TEMPERATURES FOR MUCH OF MAINLAND ALASKA AND THE  
PACIFIC COAST. A RIDGE FORECAST OVER CENTRAL NORTH AMERICA LEADS TO ENHANCED  
CHANCES OF ABOVE NORMAL TEMPERATURES FOR MUCH OF THE WEST-CENTRAL CONUS, AND  
PART OF THE GREAT LAKES REGION, EXCEPT FOR PARTS OF MONTANA AND NORTH DAKOTA.  
ANOMALOUS TROUGHING OVER THE EASTERN CONUS AND NORTHERLY FLOW TILT THE ODDS TO  
BELOW NORMAL TEMPERATURES FOR THE EASTERN CONUS AND THE LOWER MISSISSIPPI  
VALLEY.  
 
MOIST FLOW AHEAD OF A TROUGH IN THE EASTERN PACIFIC LEADS TO ENHANCED  
PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE WEST CONUS. THE POTENTIAL  
FOR SHORTWAVE ENERGY ASSOCIATED WITH ENHANCED WESTERLY 500-HPA FLOW LEADS TO  
INCREASED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR ALASKA. RIDGING LEADS  
TO ENHANCED PROBABILITIES OF BELOW NORMAL PRECIPITATION FOR MUCH OF THE CENTRAL  
CONUS. AS A TROUGH PROGRESSES OFF THE ATLANTIC COAST, BELOW NORMAL  
PRECIPITATION IS ALSO FAVORED FOR THE EASTERN CONUS.  
 
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  
GOOD MODEL AGREEMENT AND THE HIGH AMPLITUDE 500-HPA PATTERN.  
 
8-14 DAY OUTLOOK FOR MAR 14 - 20 2018  
 
THE MEAN 500-HPA FLOW PATTERN EXPECTED FOR THE WEEK-2 PERIOD FEATURES A LESS  
AMPLIFIED CIRCULATION AND THE OVERALL LONG WAVE PATTERN IS SHIFTED EASTWARD,  
ESPECIALLY WITH THE TROUGH MOVING OVER THE ATLANTIC. BELOW NORMAL HEIGHTS ARE  
EXPECTED OVER MAINLAND ALASKA AND THE ALASKA PANHANDLE, AND MUCH OF THE WESTERN  
AND THE ATLANTIC COAST STATES, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE  
ANTICIPATED OVER MUCH OF THE CENTRAL CONUS AND THE ALEUTIANS.  
 
BELOW NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF MAINLAND ALASKA, THE ALASKA  
PANHANDLE, THE WESTERN CONUS, AND THE NORTHERN HIGH PLAINS UNDERNEATH NEAR TO  
BELOW NORMAL HEIGHTS. HOWEVER, RIDGING LEADS TO ELEVATED CHANCES FOR ABOVE  
NORMAL TEMPERATURES FOR THE CENTRAL AND SOUTHERN PLAINS NORTHEASTWARD TO PARTS  
OF THE GREAT LAKES.  
 
THERE ARE ENHANCED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE WESTERN  
CONUS ASSOCIATED WITH ON SHORE FLOW AND TROUGHING. PROBABILITIES OF ABOVE  
NORMAL PRECIPITATION ARE FAVORED FOR ALASKA DUE TO STORM SYSTEMS NEAR THE SOUTH  
COAST. ABOVE NORMAL PRECIPITATION IS FAVORED FOR THE NORTHERN PLAINS AND THE  
UPPER MISSISSIPPI VALLEY, THE GREAT LAKES, THE OHIO VALLEY AND TENNESSEE  
VALLEY, WHILE BELOW NORMAL PRECIPITATION IS FAVORED FOR THE SOUTHERN HIGH  
PLAINS, CONSISTENT WITH DYNAMICAL MODEL GUIDANCE FROM THE GFS ENSEMBLE MEMBERS.  
PROBABILITIES OF BELOW NORMAL PRECIPITATION ARE ELEVATED FOR THE ATLANTIC COAST  
STATES BEHIND THE TROUGH OVER THE ATLANTIC.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 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, 20% OF YESTERDAY'S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, AND 20%  
OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO FAIR  
AGREEMENT AMONG THE SURFACE TOOLS ACROSS MUCH OF THE FORECAST DOMAIN.  
 
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  
MARCH 15.  
 
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:  
19580308 - 20060320 - 19520216 - 20090216 - 19620303  
 
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:  
19580307 - 19620306 - 20090215 - 20060306 - 20060319  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 12 - 16 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON N A OREGON B A NRN CALIF B A  
SRN CALIF B A IDAHO A A NEVADA B A  
W MONTANA N A E MONTANA B N WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A N N DAKOTA N N S DAKOTA A N  
NEBRASKA A N KANSAS A B OKLAHOMA A B  
N TEXAS B B S TEXAS N B W TEXAS A B  
MINNESOTA A B IOWA A B MISSOURI N B  
ARKANSAS B B LOUISIANA B B WISCONSIN A B  
ILLINOIS N B MISSISSIPPI B B MICHIGAN N B  
INDIANA B B OHIO B B KENTUCKY B B  
TENNESSEE B B ALABAMA B B NEW YORK B B  
VERMONT B B NEW HAMP B B MAINE N B  
MASS B B CONN B B RHODE IS B B  
PENN B B NEW JERSEY B B 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 N A  
AK ALEUTIAN N A AK WESTERN B A AK INT BSN N A  
AK S INT B A AK SO COAST B A AK PNHDL N N  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 14 - 20 2018  
 
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 B A COLORADO B A  
NEW MEXICO A B N DAKOTA B A S DAKOTA B A  
NEBRASKA A A KANSAS A N OKLAHOMA A A  
N TEXAS A A S TEXAS A N W TEXAS A B  
MINNESOTA A A IOWA A A MISSOURI A A  
ARKANSAS A A LOUISIANA A A WISCONSIN A A  
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A  
INDIANA A A OHIO A A KENTUCKY A A  
TENNESSEE N A ALABAMA A A NEW YORK N N  
VERMONT N N NEW HAMP N B MAINE N B  
MASS N B CONN N B RHODE IS N B  
PENN N N NEW JERSEY N B W VIRGINIA N N  
MARYLAND N B DELAWARE N B VIRGINIA N N  
N CAROLINA N B S CAROLINA N B GEORGIA N B  
FL PNHDL N B FL PENIN N B AK N SLOPE N A  
AK ALEUTIAN N A AK WESTERN B A AK INT BSN B A  
AK S INT B A AK SO COAST B A AK PNHDL B N  
 
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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