934  
FXUS06 KWBC 022002  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST FRI MARCH 02 2018  
 
6-10 DAY OUTLOOK FOR MAR 08 - 12 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 PRIOR TO THE PERIOD  
PROGRESSES TOWARD THE NORTHEASTERN CONUS. 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 NEAR TO 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. BELOW NORMAL HEIGHTS LEAD TO  
FAVORED BELOW NORMAL TEMPERATURES ACROSS MUCH OF MAINLAND 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 TO THE NORTHEASTERN CONUS, ABOVE NORMAL PRECIPITATION IS  
FAVORED FOR MUCH OF THE EASTERN CONUS. WEAK RIDGING LEADS TO ENHANCED  
PROBABILITIES OF BELOW NORMAL PRECIPITATION FOR MUCH OF THE CENTRAL CONUS.  
ENHANCED WESTERLY 500-HPA FLOW AND THE POTENTIAL FOR SHORTWAVE TROUGHS LEAD TO  
INCREASED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR MUCH OF ALASKA.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 10% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED  
ON DAY 8, 10% OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 10% OF  
TODAY'S OPERATIONAL 6Z GFS 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 10 - 16 2018  
 
DURING THE WEEK-2 PERIOD, A 500-HPA RIDGE CONTINUE OVER MUCH OF THE ALEUTIANS  
AND A RIDGE NEAR HUDSON BAY WEAKENS. BETWEEN THESE TWO FEATURES, HEIGHTS ARE  
EXPECTED TO LOWER OVER MAINLAND ALASKA DUE TO A TROUGH EXPECTED OVER THE STATE.  
A 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 NORTHWESTERN AND  
SOUTHEASTERN CONUS UNDERNEATH NEAR TO BELOW NORMAL HEIGHTS. HOWEVER, WEAK  
RIDGING LEADS TO ELEVATED CHANCES FOR ABOVE NORMAL TEMPERATURES FOR PARTS OF  
SOUTHERN CALIFORNIA, 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 CALIBRATED TEMPERATURES FROM THE GEFS AND ECMWF ENSEMBLE  
MEMBERS. TROUGH DEVELOPMENT OVER MAINLAND ALASKA LEADS TO ENHANCED  
PROBABILITIES OF BELOW NORMAL TEMPERATURES ACROSS THE STATE.  
 
THERE ARE ENHANCED PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE WEST  
COAST OF THE CONUS AND THE ALASKA PANHANDLE AHEAD OF A TROUGH OVER THE EASTERN  
PACIFIC. PROBABILITIES OF ABOVE NORMAL PRECIPITATION ARE ELEVATED FOR MUCH OF  
THE SOUTHEASTERN CONUS EXTENDING NORTHEASTWARD TO THE NORTHEAST UNDERNEATH  
CYCLONIC FLOW. WEAK RIDGING SLIGHTLY FAVORS BELOW NORMAL PRECIPITATION ACROSS  
THE WEST-CENTRAL CONUS. PROBABILITIES OF BELOW NORMAL PRECIPITATION ARE FAVORED  
FOR WESTERN MAINLAND ALASKA DUE TO LOW LEVEL NORTHEASTERLY FLOW OVER THE  
REGION. 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 THE ALEUTIANS.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 10% 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, 40% 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: 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:  
19510304 - 19560217 - 20060308 - 19520311 - 20090305  
 
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:  
19510303 - 20060312 - 19560217 - 20090305 - 20070225  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 08 - 12 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON N A OREGON N A NRN CALIF N A  
SRN CALIF A A IDAHO N A NEVADA N A  
W MONTANA B N E MONTANA B B WYOMING N B  
UTAH A A ARIZONA A N COLORADO A B  
NEW MEXICO A B N DAKOTA B B S DAKOTA B B  
NEBRASKA N B KANSAS A B OKLAHOMA N B  
N TEXAS N B S TEXAS N B W TEXAS A B  
MINNESOTA B B IOWA N B MISSOURI B N  
ARKANSAS B N LOUISIANA B N WISCONSIN N B  
ILLINOIS B N MISSISSIPPI B A MICHIGAN N N  
INDIANA B A OHIO B A KENTUCKY B A  
TENNESSEE B A ALABAMA B A NEW YORK N A  
VERMONT N A NEW HAMP N A MAINE A A  
MASS N A CONN N A RHODE IS N A  
PENN B A NEW JERSEY B A W VIRGINIA B A  
MARYLAND B A DELAWARE B A VIRGINIA B A  
N CAROLINA B A S CAROLINA B A GEORGIA B A  
FL PNHDL B A FL PENIN B N AK N SLOPE N A  
AK ALEUTIAN B A AK WESTERN B A AK INT BSN N A  
AK S INT B A AK SO COAST B A AK PNHDL B A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR MAR 10 - 16 2018  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON B A OREGON B A NRN CALIF B A  
SRN CALIF A A IDAHO N A NEVADA N A  
W MONTANA N N E MONTANA B B WYOMING A B  
UTAH A N ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B N S DAKOTA N B  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA N N IOWA A N MISSOURI A N  
ARKANSAS A N LOUISIANA A N WISCONSIN A N  
ILLINOIS A N MISSISSIPPI N A MICHIGAN A N  
INDIANA A N OHIO N N KENTUCKY N N  
TENNESSEE B N ALABAMA B A NEW YORK N A  
VERMONT N A NEW HAMP A A MAINE A A  
MASS N A CONN N A RHODE IS N A  
PENN N A NEW JERSEY N A W VIRGINIA B N  
MARYLAND B N DELAWARE B N 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 B  
AK ALEUTIAN B A AK WESTERN B B AK INT BSN B N  
AK S INT B B 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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