PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT MON APR 21 2008 6-10 DAY OUTLOOK VALID FOR APR 27 - MAY 01, 2008 TODAYS AVAILABLE ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE EXPECTED 500-HPA FLOW PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD. TROUGHS ARE PROGGED OVER THE GULF OF ALASKA AND OVER HUDSON BAY, EXTENDING SOUTHEASTWARD TO OVER THE GREAT LAKES. RIDGES ARE PROGGED OVER WESTERN NORTH AMERICA AND OVER THE ALEUTIANS, ALTHOUGH THE CANADIAN ENSEMBLE MEAN INDICATES ZONAL FLOW OVER THE ALEUTIANS. THE OPERATIONAL 0Z GFS AND YESTERDAYS 12Z OPERATIONAL ECMWF ARE IN FAIR AGREEMENT WITH THE ENSEMBLE MEAN SOLUTIONS ALTHOUGH THE 12Z OPERATIONAL ECMWF INDICATES A STRONG BLOCKING RIDGE OVER NORTHEASTERN CANADA NOT PROGGED BY THE OTHER MODELS. THE 6Z OPERATIONAL GFS IS THE ONLY MODEL TO SHOW A TROUGH OVER THE PLAINS. THE MODELS SHOW FAIRLY GOOD CONTINUITY WITH RESPECT TO THEIR SOLUTIONS FROM YESTERDAY WITH THE 6Z OPERATIONAL GFS PROGGING A STRONGER TROUGH OVER THE PLAINS IN TODAYS SOLUTIONS COMPARED TO ITS FORECAST FROM YESTERDAY. THE PNA INDEX WHICH RECENTLY HAS BEEN WEAKLY NEGATIVE IS FORECAST TO BE NEAR ZERO OR WEAKLY NEGATIVE THROUGH DAY 14. THE NAO INDEX WHICH RECENTLY HAS BEEN NEGATIVE IS FORECAST TO TREND TOWARDS ZERO BY DAY 7 AND REMAIN NEAR ZERO THROUGH DAY 14. TODAYS BLEND CHART INDICATES NEAR TO ABOVE NORMAL HEIGHTS OVER MOST OF THE CONUS EXCEPT OVER FLORIDA, THE NORTHERN GREAT LAKES, THE FAR NORTHERN ROCKIES/PLAINS AND THE PACIFIC NORTHWEST WHERE NEAR TO BELOW NORMAL HEIGHTS ARE FORECAST. HEIGHTS OVER THE ALEUTIANS AND SOUTHWEST ALASKA ARE FORECAST TO BE ABOVE NORMAL WHILE NEAR TO BELOW NORMAL HEIGHTS ARE PROGGED OVER NORTHEASTERN ALASKA. THE RIDGE OVER THE WEST/CENTRAL CONUS SHOULD LEAD TO WARMER AND DRIER THAN NORMAL WEATHER FOR MUCH OF THE SOUTHWEST. THE TROUGH OVER THE GULF OF ALASKA SHOULD LEAD TO COOLER AND WETTER THAN NORMAL CONDITIONS OVER THE PACIFIC NORTHWEST. THE TROUGH NEAR THE GREAT LAKES SHOULD ALSO LEAD TO COOLER AND WETTER THAN NORMAL CONDITIONS FOR THAT REGION. ANOMALOUS NORTHERLY FLOW SHOULD CAUSE COOLER AND DRIER THAN NORMAL WEATHER FOR THE ALEUTIANS, SOUTHERN ALASKA AND THE ALASKAN PANHANDLE. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...10 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...30 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 35 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: ECMWF ENSEMBLE FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO FAIRLY GOOD AGREEMENT AMONG MODELS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN, NEURAL NET AND ANALOG SPECIFICATIONS FROM THE BLENDED HEIGHT FIELD, THE KLEIN PROBABILITIES FROM THE ECMWF AND CANADIAN ENSEMBLES, THE CDC TEMPERATURE FORECAST, THE CPC AUTO FORECAST, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE FORECAST, AND TELECONNECTIONS ON POSITIVE HEIGHT ANOMALY CENTERS AT 36N 110W AND 50N 170W. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND, DAILY PRECIPITATION FORECASTS FROM VARIOUS MODELS, THE CDC PRECIPITATION FORECAST, THE CPC AUTO FORECAST, AND TELECONNECTIONS ON POSITIVE HEIGHT ANOMALY CENTERS AT 36N 110W AND 50N 170W. 8-14 DAY OUTLOOK FOR APR 29 - MAY 05, 2008: FOR WEEK 2 THE 0Z GFS AND CANADIAN ENSEMBLE MEANS INDICATE A SLOW EASTWARD PROGRESSION AND DEAMPLIFICATION OF THE 500-HPA CIRCULATION PATTERN FROM THAT DEPICTED DURING THE 6-10 DAY PERIOD. THE 6Z GFS ENSEMBLE MEAN IS SIGNIFICANTLY MORE AMPLIFIED WITH THE PROGGED FLOW PATTERN AND WAS DISCOUNTED. THE 0Z OPERATIONAL GFS IS MORE AMPLIFIED AND MORE PROGRESSIVE WITH THE EXPECTED FLOW PATTERN COMPARED TO THE ENSEMBLE MEAN SOLUTIONS. THE BLEND CHART SHOWS NEAR TO ABOVE NORMAL HEIGHTS ACROSS MOST OF THE CONUS EXCEPT FOR FLORIDA AND THE NORTHWESTERN QUARTER OF THE COUNTRY WHERE NEAR TO BELOW NORMAL HEIGHTS ARE INDICATED. HEIGHTS OVER ALASKA ARE PROGGED TO BE ABOVE NORMAL. THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK 2 ARE MOSTLY SIMILAR TO THOSE FORECAST FOR THE 6-10 DAY PERIOD. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 15 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...50 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 35 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS AVERAGE... 3 ON A SCALE OF 1 TO 5 THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTOBLEND FORECAST, ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND, THE CDC TEMPERATURE FORECAST, KLEIN PROBABILITIES FROM THE CANADIAN ENSEMBLE, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE FORECAST, AND TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 53N 159W. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND, THE CPC AUTO FORECAST, THE CDC PRECIPITATION FORECAST, AND TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 53N 159W. FORECASTER: R. SCHECHTER NOTES: OPERATIONAL CHANGE: AS OF JULY 5 2005 SHADED MAPS HAVE REPLACED THE CONTOUR-ONLY MAPS ON THE CPC WEB SITE. THE CONTOURED MAPS ARE STILL AVAILABLE AT THEIR CURRENT FILE NAMES - SO DIRECT-LINKED USERS ARE NOT AFFECTED. AWIPS GRAPHICS ARE ALSO NOT AFFECTED BY THIS CHANGE. AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OTHERWISE - FORECASTS INCORPORATE FORECASTER INPUT. 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 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 NARRATIVE DESCRIPTION OF THE FORECAST PATTERNS FOR TEMPERATURE AND PRECIPITATION FOR BOTH THE 6-10 OR 8-14 DAY PERIODS HAS BEEN DISCONTINUED. THE STATE TABLES FOR BOTH THE 6-10 AND 8-14 DAY PERIODS ARE NOW CONTAINED IN THIS MESSAGE...AVAILABLE AS PMDMRD ON AWIPS. THE CLIMATE PREDICTION CENTER USES 1971-2000 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 MAY 16. NEW NOTE EFFECTIVE MAR 16 2004: THE GLOSSARY FORMERLY FOUND AT THIS LOCATION WILL NO LONGER BE TRANSMITTED AS PART OF THIS MESSAGE. IF YOU WISH TO SEE THE DEFINITIONS OF TERMS USED IN THESE MESSAGES... PLEASE GO TO THE CPC WEB PAGE AT (USE LOWER CASE) HTTP://WWW.CPC.NCEP.NOAA.GOV AND FOLLOW THE APPROPRIATE LINKS. 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: 19790401 - 19540423 - 19900428 - 19580424 - 19620408 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 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES: 19790331 - 19540423 - 19580424 - 19810408 - 19670417 6 to 10 day Outlook Table OUTLOOK FOR APR 27 - MAY 01, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON N A NRN CALIF A N SRN CALIF A B IDAHO A N NEVADA A B W MONTANA B N E MONTANA A N WYOMING A B UTAH A B ARIZONA A B COLORADO A B NEW MEXICO A B N DAKOTA N N S DAKOTA A N NEBRASKA A B KANSAS A B OKLAHOMA A B N TEXAS A B S TEXAS N B W TEXAS A B MINNESOTA N A IOWA A N MISSOURI A N ARKANSAS N B LOUISIANA N B WISCONSIN N A ILLINOIS N A MISSISSIPPI N B MICHIGAN B A INDIANA N A OHIO N A KENTUCKY N A TENNESSEE N N ALABAMA N B 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 N A NEW JERSEY N N W VIRGINIA N N MARYLAND A N DELAWARE A N VIRGINIA A N N CAROLINA A B S CAROLINA A B GEORGIA N B FL PNHDL N B FL PENIN B B AK N SLOPE N A AK ALEUTIAN B B AK WESTERN N A AK INT BSN B A AK S INT B B AK SO COAST B B AK PNHDL B B 8 to 14 day Outlook Table OUTLOOK FOR APR 29 - MAY 05, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON B A NRN CALIF B A SRN CALIF N N IDAHO B N NEVADA N N W MONTANA B A E MONTANA B A WYOMING N B UTAH N B ARIZONA A B COLORADO A B NEW MEXICO A B N DAKOTA B N S DAKOTA N N NEBRASKA N B KANSAS A B OKLAHOMA A N N TEXAS A B S TEXAS A B W TEXAS A B MINNESOTA B N IOWA N N MISSOURI A N ARKANSAS A N LOUISIANA A B WISCONSIN B A ILLINOIS N A MISSISSIPPI A B MICHIGAN B A INDIANA N A OHIO N A KENTUCKY A N TENNESSEE A N ALABAMA A B NEW YORK N A VERMONT B A NEW HAMP N N MAINE B N MASS N N CONN A N RHODE IS A N PENN A N NEW JERSEY A N W VIRGINIA A N MARYLAND A N DELAWARE A N VIRGINIA A B N CAROLINA A B S CAROLINA A B GEORGIA A B FL PNHDL A B FL PENIN A B AK N SLOPE N N AK ALEUTIAN B N AK WESTERN B N AK INT BSN B B 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. $$