PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT WED APR 23 2008 6-10 DAY OUTLOOK VALID FOR APR 29 - MAY 03, 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 NEAR THE GREAT LAKES. RIDGES ARE PROGGED OVER WEST/CENTRAL NORTH AMERICA AND OVER THE ALEUTIANS. IN GENERAL THE CONUS IS DOMINATED BY FAST ZONAL FLOW. THE 6Z GFS ENSEMBLE MEAN AND CANADIAN ENSEMBLE MEAN ARE GENERALLY MORE PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES COMPARED TO THE OTHER ENSEMBLE MEAN SOLUTIONS. THE OPERATIONAL 0Z AND 6Z GFS ARE MORE AMPLIFIED AND PROGRESSIVE THAN THE 0Z ENSEMBLE MEAN. YESTERDAYS 12Z OPERATIONAL ECMWF IS MORE AMPLIFIED THAN THE ECMWF ESNEMBLE MEAN, ESPECIALLY IN REGARD TO THE TROUGH FORECAST NEAR THE GREAT LAKES. THE ENSEMBLE MEAN FORECASTS SHOW FAIR CONTINUITY WITH RESPECT TO THEIR SOLUTIONS FROM YESTERDAY ALTHOUGH TODAYS ECMWF ENSEMBLE MEAN IS MORE AMPLIFIED WITH THE TROUGH NEAR THE GREAT LAKES. THE ECMWF ENSEMBLE MEAN WAS GIVEN HEAVY WEIGHT IN TODAYS BLEND CHART SINCE IT HAS BEEN SIGNIFICANTLY OUTPERFORMING THE OTHER MODELS RECENTLY. THE PNA INDEX WHICH RECENTLY HAS BEEN WEAKLY NEGATIVE IS FORECAST TO TREND TOWARDS ZERO BY DAY 7, BE NEGATIVE AT DAY 10, AND TREND BACK TOWARDS ZERO BY DAY 14. THE NAO INDEX WHICH RECENTLY HAS BEEN NEGATIVE IS FORECAST TO TREND TOWARDS ZERO BY DAY 7 AND THEN BECOME WEAKLY NEGATIVE THROUGH DAY 14. TODAYS BLEND CHART INDICATES NEAR TO ABOVE NORMAL HEIGHTS OVER PARTS OF THE SOUTHWEST, THE SOUTHERN ROCKIES, THE SOUTHERN PLAINS, THE ALEUTIANS, AND SOUTHERN ALASKA, WHILE NEAR TO BELOW NORMAL HEIGHTS ARE PROGGED OVER THE RWEMAINDER OF THE CONUS, NORTHERN ALASKA AND THE ALASKAN PANHANDLE. THE WEAK RIDGE OVER THE WEST/CENTRAL CONUS SHOULD LEAD TO WARMER AND DRIER THAN NORMAL WEATHER FOR MUCH OF THE SOUTHWEST AND PLAINS STATES. 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 PARTS OF THE NORTHEASTERN CONUS. 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 6Z GFS CENTERED ON DAY 8...10 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...10 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...10 PERCENT OF TODAY'S 6Z 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 ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO FAIR AGREEMENT AMONG THE MODELS AND FORECAST TOOLS. 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 VARIOUS ENSEMBLES, THE CDC TEMPERATURE FORECAST, THE CPC AUTO FORECAST, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE FORECAST, TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 57N 59W, AND TELECONNECTIONS ON A NEGATIVE HEIGHT ANOMALY CENTER AT 46N 124W. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND, DAILY PRECIPITATION FORECASTS FROM THE VARIOUS MODELS, THE CDC PRECIPITATION FORECAST, THE CPC AUTO FORECAST, NEURAL NET PROBABILITIES FROM THE VARIOUS ENSEMBLES, TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 57N 55W, AND TELECONNECTIONS ON A NEGATIVE HEIGHT ANOMALY CENTER AT 46N 124W. 8-14 DAY OUTLOOK FOR MAY 01 - 07 2008: FOR WEEK 2 THE GFS SUPERENSEMBLE AND CANADIAN ENSEMBLE MEANS INDICATE A SLOW EASTWARD PROGRESSION AND SLIGHT DEAMPLIFICATION OF THE 500-HPA CIRCULATION PATTERN FROM THAT DEPICTED DURING THE 6-10 DAY PERIOD. THE 0Z AND 6Z GFS ENSEMBLE MEANS ARE SIMILAR TO THE GFS SUPERENSEMBLE MEAN. THE 0Z AND 6Z OPERATIONAL GFS ARE IN GOOD AGREEMENT WITH EACH OTHER BUT GENERALLY ARE MORE AMPLIFED THAN THE ENSEMBLE MEAN SOLUTIONS. THE BLEND CHART SHOWS NEAR TO ABOVE NORMAL HEIGHTS ACROSS THE GREAT LAKES, MISSISSIPPI VALLEY, THE SOUTHERN PLAINS, AND ALASKA, WHILE NEAR TO BELOW NORMAL HEIGHTS ARE FORECAST ALONG THE EAST COAST AND OVER MUCH OF THE WESTERN HALF OF THE CONUS. AS HEIGHTS SLOWLY RISE OVER THE EAST/CENTRAL CONUS, THE AREA OF ABOVE NORMAL TEMPERATURES FORECAST OVER THE WEST/CENTRAL PART OF THE COUNTRY DURING THE 6-10 DAY PERIOD WILL SPREAD SLOWLY EAST/NORTHEAST TOWARDS THE OHIO VALLEY. PRECIPIATION IS LIKELY TO BE BELOW MEDIAN OVER MUCH OF THE EASTERN CONUS AS A RIDGE BUILDS TOWARD THE AREA. A TROUGH DROPPING SOUTHEAST FROM THE PACIFIC NORTHWEST WILL LIKELY CAUSE ABOVE MEDIAN PRECIPITATION OVER MUCH OF THE WEST AND CENTRAL CONUS. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 15 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...15 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...10 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...10 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 40 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO FAIR AGREEMENT AMONGST THE MODELS AND FORECAST TOOLS. 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 AND GFS ENSEMBLES, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE FORECAST, AND TELECONNECTION ON A NEGATIVE HEIGHT ANOMALY CENTER AT 36N 60W. 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, NEURAL NET PROBABLITIES FROM THE GFS ENSEMBLE, AND TELECONNECTIONS ON A NEGATIVE HEIGHT ANOMALY CENTER AT 36N 60W. 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: 19900428 - 19530409 - 19580425 - 19540424 - 19670417 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: 19900428 - 19540423 - 19580425 - 19790402 - 19530409 6 to 10 day Outlook Table OUTLOOK FOR APR 29 - MAY 03, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON B A NRN CALIF B A SRN CALIF B N IDAHO B A NEVADA N N W MONTANA B A E MONTANA B N WYOMING N B UTAH N B ARIZONA N B COLORADO A B NEW MEXICO A B N DAKOTA B N S DAKOTA N N NEBRASKA A B KANSAS A B OKLAHOMA A B N TEXAS N B S TEXAS N B W TEXAS A B MINNESOTA B N IOWA N N MISSOURI N N ARKANSAS N B LOUISIANA N B WISCONSIN B N ILLINOIS B N MISSISSIPPI N B MICHIGAN B N INDIANA B N OHIO B N KENTUCKY B N TENNESSEE B N ALABAMA N N NEW YORK B A VERMONT B A NEW HAMP B A MAINE N A MASS B A CONN B A RHODE IS B A PENN B A NEW JERSEY B A W VIRGINIA B N MARYLAND B N DELAWARE B N VIRGINIA B N N CAROLINA B N S CAROLINA B N GEORGIA N N FL PNHDL N N FL PENIN N B AK N SLOPE N A AK ALEUTIAN B B AK WESTERN B B AK INT BSN B N AK S INT B B AK SO COAST B B AK PNHDL B B 8 to 14 day Outlook Table OUTLOOK FOR MAY 01 - 07, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B A NRN CALIF B A SRN CALIF B A IDAHO B N NEVADA B A W MONTANA B N E MONTANA B A WYOMING B N UTAH B A ARIZONA B A COLORADO N N NEW MEXICO N N N DAKOTA N A S DAKOTA N A NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A A S TEXAS A A W TEXAS A A MINNESOTA A A IOWA A A MISSOURI A A ARKANSAS A A LOUISIANA A N WISCONSIN A A ILLINOIS A N MISSISSIPPI A N MICHIGAN A N INDIANA A N OHIO A N KENTUCKY A B TENNESSEE A B ALABAMA A B NEW YORK B N VERMONT B B NEW HAMP B B MAINE B B MASS B B CONN B B RHODE IS B B PENN N B NEW JERSEY B B W VIRGINIA N B MARYLAND B B DELAWARE B B VIRGINIA N B N CAROLINA N B S CAROLINA N B GEORGIA N B FL PNHDL N B FL PENIN B B AK N SLOPE A N AK ALEUTIAN B B AK WESTERN B B AK INT BSN N N AK S INT B B AK SO COAST B B AK PNHDL N 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. $$