785  
FXUS06 KWBC 012010  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST THU MARCH 01 2018  
 
6-10 DAY OUTLOOK FOR MAR 07 - 11 2018  
 
TODAY'S MODEL ENSEMBLE SOLUTIONS FEATURE STRONG POSITIVE 500-HPA HEIGHT  
ANOMALIES AT HIGH LATITUDES CONSISTENT WITH A NEGATIVE AO PATTERN. RIDGES ARE  
PREDICTED SOUTH OF THE ALEUTIANS AS WELL AS OVER EASTERN CANADA CENTERED NEAR  
BAFFIN ISLAND. FARTHER TO THE SOUTH, BELOW NORMAL HEIGHTS ARE EXPECTED FOR MUCH  
OF THE CONUS AS A TROUGH OVER THE NORTH-CENTRAL CONUS EARLY IN THE PERIOD  
PROGRESSES TOWARD THE NORTHEASTERN CONUS LATER IN THE PERIOD. POSITIVE HEIGHT  
ANOMALIES ARE INDICATED FOR PARTS OF THE SOUTHWESTERN CONUS AS HEIGHTS RISE IN  
ADVANCE OF A TROUGH PREDICTED OVER THE EASTERN PACIFIC. ENSEMBLE SPREAD IS LOW  
TO MODERATE TODAY OVER MUCH OF THE FORECAST DOMAIN.  
 
BELOW NORMAL HEIGHTS LEAD TO ENHANCED PROBABILITIES OF BELOW NORMAL  
TEMPERATURES ACROSS THE NORTHERN PLAINS AND THE NORTHWESTERN CONUS.  
TELECONNECTIONS ASSOCIATED WITH THE RIDGE OVER EASTERN CANADA FAVOR ABOVE  
NORMAL TEMPERATURES FOR PARTS OF THE NORTHEAST. THERE ARE ENHANCED  
PROBABILITIES OF BELOW NORMAL TEMPERATURES FOR THE SOUTHEASTERN CONUS DUE TO A  
TROUGH AND ASSOCIATED BELOW NORMAL HEIGHTS. RIDGING EARLY IN THE PERIOD AND  
ABOVE NORMAL SSTS LEAD TO FAVORED ABOVE NORMAL TEMPERATURES ACROSS PARTS OF  
NORTHERN MAINLAND ALASKA. TROUGH DEVELOPMENT DOWNSTREAM FAVORS BELOW NORMAL  
TEMPERATURES FOR PARTS OF SOUTH-CENTRAL AND SOUTHEASTERN ALASKA, INCLUDING THE  
PANHANDLE.  
 
MOIST FLOW AHEAD OF A TROUGH IN THE EASTERN PACIFIC LEADS TO ENHANCED  
PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE WEST COAST OF THE CONUS. AS  
A TROUGH PROGRESSES FROM WEST TO EAST FROM THE NORTH-CENTRAL TO THE  
NORTHEASTERN CONUS, NEAR TO ABOVE NORMAL PRECIPITATION IS FAVORED FOR PARTS OF  
THE EASTERN CONUS. WEAK RIDGING LEADS TO ENHANCED PROBABILITIES OF BELOW NORMAL  
PRECIPITATION FOR MUCH OF THE WEST-CENTRAL CONUS. ENHANCED WESTERLY 500-HPA  
FLOW AND THE POTENTIAL FOR SHORTWAVE TROUGHS LEAD TO INCREASED PROBABILITIES OF  
ABOVE NORMAL PRECIPITATION FOR MAINLAND ALASKA AND THE ALEUTIANS.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 15% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 15% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED  
ON DAY 8, 10% OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 40% OF  
TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF TODAY'S OPERATIONAL  
0Z ECMWF CENTERED ON DAY 8, AND 10% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN  
CENTERED ON DAY 8  
 
 
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO FAIR  
MODEL AGREEMENT.  
 
8-14 DAY OUTLOOK FOR MAR 09 - 15 2018  
 
DURING THE WEEK-2 PERIOD POSITIVE 500-HPA HEIGHT ANOMALIES CONTINUE OVER MUCH  
OF THE HIGH LATITUDES DUE TO RIDGES SOUTH OF THE ALEUTIANS AND NEAR HUDSON BAY.  
BETWEEN THESE TWO FEATURES, HEIGHTS ARE EXPECTED TO LOWER OVER MAINLAND ALASKA  
AS TROUGHS ARE EXPECTED NEAR THE BERING STRAIT AS WELL AS OVER THE GULF OF  
ALASKA. THE TROUGH OVER THE GULF OF ALASKA IS FORECAST TO EXTEND SOUTHWARD OVER  
THE EASTERN PACIFIC, OFF THE WEST COAST OF THE CONUS, ALLOWING FOR A WEAK RIDGE  
TO DEVELOP DOWNSTREAM OVER PARTS OF THE WEST-CENTRAL CONUS. CYCLONIC FLOW IS  
EXPECTED FARTHER TO THE EAST OVER THE EASTERN CONUS. THE GREATEST WEIGHT IN THE  
WEEK-2 MANUAL 500-HPA HEIGHT BLEND WAS GIVEN TO THE 0Z ECMWF ENSEMBLE MEAN  
SOLUTION DUE TO CONSIDERATIONS OF RECENT SKILL.  
 
BELOW NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE WESTERN AND SOUTHEASTERN  
CONUS UNDERNEATH NEAR TO BELOW NORMAL HEIGHTS. HOWEVER, WEAK RIDGING LEADS TO  
ELEVATED CHANCES FOR ABOVE NORMAL TEMPERATURES FOR PARTS OF THE SOUTHWEST, THE  
CENTRAL AND SOUTHERN PLAINS NORTHEASTWARD TO PARTS OF THE UPPER MISSISSIPPI  
VALLEY. ABOVE NORMAL TEMPERATURES ARE SLIGHTLY FAVORED FOR PARTS OF THE  
NORTHEASTERN CONUS AND GREAT LAKES CONSISTENT WITH TELECONNECTIONS ASSOCIATED  
WITH A POSITIVE HEIGHT ANOMALY CENTER EXPECTED NEAR HUDSON BAY. TROUGH  
DEVELOPMENT OVER MAINLAND ALASKA LEADS TO ENHANCED PROBABILITIES OF BELOW  
NORMAL TEMPERATURES ACROSS MUCH OF THE STATE.  
 
THERE ARE ENHANCED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE WEST  
COAST OF THE CONUS AHEAD OF A TROUGH OVER THE EASTERN PACIFIC. PROBABILITIES OF  
ABOVE NORMAL PRECIPITATION ARE ELEVATED FOR MUCH OF THE SOUTHEASTERN CONUS  
EXTENDING NORTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY UNDERNEATH CYCLONIC  
FLOW AND CONSISTENT WITH TELECONNECTIONS FROM THE EXPECTED POSITIVE HEIGHT  
ANOMALY CENTER NEAR HUDSON BAY. BELOW NORMAL PRECIPITATION IS FAVORED FOR MUCH  
OF THE GREAT LAKES, PARTS OF THE OHIO VALLEY AND THE MID-ATLANTIC REGIONS  
NORTHWARD TO THE NORTHEAST DUE TO SUBSIDENCE BEHIND THE MEAN TROUGH AXIS. WEAK  
RIDGING SLIGHTLY FAVORS NEAR TO BELOW NORMAL PRECIPITATION ACROSS THE  
WEST-CENTRAL CONUS. THE POTENTIAL FOR SHORTWAVE ENERGY ASSOCIATED WITH TROUGHS  
NEAR THE BERING STRAIT AND GULF OF ALASKA LEAD TO INCREASED PROBABILITIES OF  
ABOVE NORMAL PRECIPITATION FOR MUCH OF ALASKA.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 15% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 15% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED  
ON DAY 11, 15% OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 45% OF  
TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 10% 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: Y. FAN  
 
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:  
19560217 - 19940210 - 19630314 - 19570209 - 19550311  
 
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:  
19560216 - 19570208 - 19510302 - 19940210 - 19630314  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 07 - 11 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A NRN CALIF N A  
SRN CALIF N A IDAHO B A NEVADA N A  
W MONTANA B N E MONTANA B B WYOMING B B  
UTAH N A ARIZONA A N COLORADO N B  
NEW MEXICO A B N DAKOTA B B S DAKOTA B B  
NEBRASKA B B KANSAS B B OKLAHOMA B B  
N TEXAS N B S TEXAS N B W TEXAS A N  
MINNESOTA B B IOWA B B MISSOURI B N  
ARKANSAS B N LOUISIANA B N WISCONSIN B B  
ILLINOIS B B MISSISSIPPI B N MICHIGAN N B  
INDIANA B B OHIO B B KENTUCKY B B  
TENNESSEE B N ALABAMA B A NEW YORK N A  
VERMONT A A NEW HAMP A A MAINE A A  
MASS A A CONN N A RHODE IS N A  
PENN N A NEW JERSEY N A W VIRGINIA B N  
MARYLAND B A DELAWARE B A VIRGINIA B N  
N CAROLINA B N S CAROLINA B N GEORGIA B A  
FL PNHDL B A FL PENIN B A AK N SLOPE A A  
AK ALEUTIAN N A AK WESTERN A A AK INT BSN A A  
AK S INT B A AK SO COAST B A AK PNHDL B A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 09 - 15 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 N E MONTANA B N WYOMING N N  
UTAH N A ARIZONA N A COLORADO A B  
NEW MEXICO A B N DAKOTA N N S DAKOTA N N  
NEBRASKA A N KANSAS A N OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA A A IOWA A A MISSOURI A A  
ARKANSAS N A LOUISIANA A A WISCONSIN A N  
ILLINOIS A N MISSISSIPPI N A MICHIGAN A B  
INDIANA N N OHIO N B KENTUCKY N N  
TENNESSEE B A ALABAMA B A NEW YORK N B  
VERMONT A B NEW HAMP A B MAINE A B  
MASS N B CONN N B RHODE IS N B  
PENN N B NEW JERSEY N B W VIRGINIA B N  
MARYLAND B B DELAWARE N B VIRGINIA B N  
N CAROLINA B N S CAROLINA B A GEORGIA B A  
FL PNHDL B A FL PENIN B N AK N SLOPE B N  
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A  
AK S INT B A AK SO COAST B N AK PNHDL B A  
 
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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