PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT TUE AUG 21 2007 6-10 DAY OUTLOOK VALID FOR AUG 27 - 31 2007 TODAYS ENSEMBLE MEANS ARE IN RELATIVELY GOOD AGREEMENT IN DEPICTING A LOW AMPLITUDE 500-HPA FLOW PATTERN OVER MOST OF THE FORECAST DOMAIN. THE MAIN FORECAST FEATURES ARE A MID LATITUDE ZONALLY ORIENTED JET STRADDLING THE U.S./CANADIAN BORDER... SUBTROPICAL RIDGING STRETCHING FROM THE ATLANTIC ACROSS THE SOUTHERN TIER OF THE CONUS... AND A LOW FORECAST OVER THE GULF OF ALASKA. MOST OF TODAYS MODELS DO NOT SHOW AS MUCH OF A WEAKNESS IN THE SUBTROPICAL RIDGING OVER THE SOUTHEASTERN CONUS THAN THEIR SOLUTIONS FROM YESTERDAY. THIS TREND... SHOULD IT HOLD... WOULD ALLOW WEAK POSITIVE HEIGHT ANOMALIES TO OVERSPREAD MOST OF THE EASTERN THIRD OF THE CONUS... RESULTING IN NEAR TO ABOVE NORMAL TEMPERATURES. LIKEWISE... SLIGHTLY POSITIVE HEIGHT ANOMALIES AHEAD OF A WEAK TROUGH FORECAST NEAR THE PACIFIC NORTHWEST COAST WOULD FAVOR NEAR TO ABOVE NORMAL TEMPERATURES FOR MUCH OF THE WESTERN THIRD OF THE CONUS. TO THE SOUTH OF THE SUBTROPICAL RIDGE AXIS... MOIST EASTERLY FLOW IS FORECAST IN COMBINATION WITH WEAK NEGATIVE ANOMALIES FAVORING ABOVE NORMAL PRECIPITATION FOR FLORIDA AND THE SOUTHCENTRAL CONUS WITH NEAR TO BELOW NORMAL TEMPERATURES. THE PROBABILITIES OF ABOVE NORMAL PRECIPITATION FOR THE SOUTHWEST/SOUTHCENTRAL CONUS WOULD ALSO BE ENHANCED IF MOISTURE FROM THE REMNANTS OF HURRICANE DEAN IS DRAWN NORTHWARD (ALTHOUGH THE CURRENT THINKING IS THAT MOST OF THE SIGNIFICANT EFFECTS WILL BE TO THE SOUTH OF THE U.S./MEXICO BORDER). ABOVE NORMAL PRECIPITATION IS ALSO LIKELY FOR MUCH OF THE MID ATLANTIC COAST AS ITS POSITION AT THE NORTHERN PERIPHERY OF THE FORECAST SUBTROPICAL RIDGE MAY FAVOR STATIONARY FRONTS IN THE VICINITY DURING THE OUTLOOK PERIOD. FURTHER TO THE NORTH AND WEST... NEAR TO BELOW NORMAL PRECIPITATION ARE LIKELY FOR MUCH OF THE NORTHERN TIER OF THE CONUS UNDERNEATH FAST ZONAL FLOW. ALASKA IS EXPECTED TO BE DOMINATED BY THE FORECAST CLOSED LOW FORECAST JUST SOUTH OF THE SOUTH COAST. ONSHORE FLOW TO THE SOUTH OF THIS LOW IS EXPECTED TO RESULT IN NEAR TO ABOVE NORMAL PRECIPITATION FOR THE PANHANDLE WHILE OFFSHORE FLOW AND POSITIVE HEIGHT ANOMALIES TO THE NORTH OF THIS LOW ARE EXPECTED TO RESULT IN DRIER AND WARMER THAN NORMAL CONDITIONS FOR MUCH OF THE REST OF THE STATE. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 40 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: ECMWF ENSEMBLE MEAN FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS BELOW AVERAGE... 2 ON A SCALE OF 1 TO 5... DUE TO A RELATIVELY LOW AMPLITUDE FLOW PATTERN AND RELATIVELY POOR AGREEMENT AMONG THE SURFACE TOOLS FOR THE EASTERN CONUS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO FORECAST... CPC 2 METER CALIBRATED TEMPERATURES... NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURES... AND THE CDC REFORECAST TEMPERATURE TEMPERATURE TOOL. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO FORECAST... THE CDC REFORECAST PRECIPITATION TOOL... AND CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES. 8-14 DAY OUTLOOK FOR AUG 29 - SEP 04, 2007: FOR WEEK 2... TODAYS MODELS DEPICT A RELATIVELY SIMILAR PATTERN TO THAT FORECAST DURING THE 6 TO 10 DAY PERIOD. THE ENSEMBLE MEANS PERSIST THE ZONALLY ORIENTED MID-LEVEL JET NEAR THE U.S./CANADIAN BORDER WITH THE MAIN FEATURES CONTINUING TO BE THE SUBTROPICAL RIDGE FORECAST FOR THE SOUTHERN TIER OF THE CONUS AND THE LOW FORECAST TO BE IN THE VICINITY OF THE SOUTH COAST OF ALASKA. MOST OF THE ENSEMBLE MEANS DO... HOWEVER... DEPICT MORE OF A WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE EAST-CENTRAL CONUS RELATIVE TO THE 6 TO 10 DAY TIME FRAME. THIS SUGGESTS THAT A COOLING TREND MAY DEVELOP OVER PARTS OF THE EAST-CENTRAL CONUS DURING THE WEEK 2 PERIOD. MOIST SOUTHWESTERLY FLOW AHEAD OF THIS WEAKNESS IN THE RIDGE WOULD FAVOR ABOVE NORMAL PRECIPITATION FOR MUCH OF THE IMMEDIATE EAST COAST. WETTER THAN NORMAL CONDITIONS ARE ALSO LIKELY TO THE SOUTH OF THE RIDGE AXIS NEAR THE RIO GRANDE DUE TO THE EXPECTED MOIST EASTERLY MID LEVEL FLOW FROM THE GULF OF MEXICO. MOST OF THE REMAINDER OF THE CONUS SHOULD EXPERIENCE NEAR TO BELOW NORMAL PRECIPITATION WITH NEAR TO ABOVE NORMAL TEMPERATURES UNDERNEATH WEAK POSITIVE HEIGHT ANOMALIES AND A LOW AMPLITUDE FLOW PATTERN. LIKEWISE MOST OF ALASKA IS EXPECTED TO BE WARMER AND DRIER THAN NORMAL TO THE NORTH OF THE EXPECTED MEAN STORM TRACK WITH THE EXCEPTION BEING THE PANHANDLE WHERE ONSHORE FLOW AROUND THE BASE OF THE GULF OF ALASKA TROUGH SHOULD RESULT IN NEAR TO ABOVE NORMAL PRECIPITATION. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 20 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...30 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...30 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 20 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS BELOW AVERAGE... 2 ON A SCALE OF 1 TO 5... DUE TO THE RELATIVELY LOW AMPLITUDE FORECAST PATTERN EXPECTED DURING THE OUTLOOK PERIOD. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO FORECAST... CPC 2 METER CALIBRATED TEMPERATURES... NORTH AMERICAN ENSEMBLE SYSTEM TEMPERATURES... AND THE CDC REFORECAST TEMPERATURE TEMPERATURE TOOL. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO FORECAST... THE CDC REFORECAST PRECIPITATION TOOL... AND CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES. FORECASTER: HANDEL 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 SEPTEMBER 20. 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: 19620817 - 19680812 - 19750818 - 19780902 - 19770824 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: 19680811 - 19780903 - 19820828 - 19620817 - 19720811 6 to 10 day Outlook Table OUTLOOK FOR AUG 27 - 31, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N N NRN CALIF A N SRN CALIF A N IDAHO A B NEVADA A N W MONTANA A B E MONTANA A B WYOMING A N UTAH A N ARIZONA A N COLORADO A N NEW MEXICO A A N DAKOTA A B S DAKOTA A N NEBRASKA N N KANSAS N N OKLAHOMA N A N TEXAS N A S TEXAS B A W TEXAS N A MINNESOTA N B IOWA N B MISSOURI N N ARKANSAS N N LOUISIANA B A WISCONSIN N B ILLINOIS N B MISSISSIPPI N N MICHIGAN N B INDIANA N B OHIO A N KENTUCKY N N TENNESSEE N N ALABAMA N N NEW YORK A A VERMONT A N NEW HAMP A N MAINE A N MASS A A CONN A A RHODE IS A A PENN A A NEW JERSEY A A W VIRGINIA A A MARYLAND A A DELAWARE A A VIRGINIA A A N CAROLINA A A S CAROLINA A N GEORGIA N N FL PNHDL N N FL PENIN N A AK N SLOPE A B AK ALEUTIAN A B AK WESTERN A B AK INT BSN A B AK S INT A B AK SO COAST A B AK PNHDL N A 8 to 14 day Outlook Table OUTLOOK FOR AUG 29 - SEP 04, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A B OREGON A B NRN CALIF A B SRN CALIF A N IDAHO A B NEVADA A N W MONTANA A B E MONTANA A B WYOMING A N UTAH A N ARIZONA N A COLORADO N N NEW MEXICO N A N DAKOTA N B S DAKOTA N N NEBRASKA N N KANSAS N N OKLAHOMA B N N TEXAS B N S TEXAS B A W TEXAS N A MINNESOTA N B IOWA N N MISSOURI B N ARKANSAS B N LOUISIANA B N WISCONSIN N B ILLINOIS N N MISSISSIPPI B N MICHIGAN N B INDIANA N N OHIO N N KENTUCKY B N TENNESSEE B N ALABAMA N N NEW YORK N N VERMONT N N NEW HAMP N N MAINE A N MASS N N CONN N N RHODE IS N N PENN N N NEW JERSEY N A W VIRGINIA N A MARYLAND N A DELAWARE N A VIRGINIA N A N CAROLINA N A S CAROLINA N A GEORGIA N A FL PNHDL N N FL PENIN A N AK N SLOPE A B AK ALEUTIAN A B AK WESTERN A B AK INT BSN A B AK S INT A B AK SO COAST A B AK PNHDL N 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. $$