PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT FRI SEP 29 2006 6-10 DAY OUTLOOK VALID FOR OCT 05 - 09 2006 MOST OF TODAYS NUMERICAL MODELS REMAIN IN GOOD AGREEMENT ON THE FORECAST 500-HPA FLOW PATTERN AND ARE CONSISTENT WITH YESTERDAYS FORECASTS. THE CANADIAN ENSEMBLE MEAN WAS NOT AVILABLE TODAY. THE GFS OPERATIONAL RUNS CONTINUE TO HAVE A MUCH STRONGER CUTOFF LOW NEAR THE CALIFORNIA COAST THAN ANY ANY OF THE OTHER MODELS. THE HEIGHT PATTERN AS SHOWN BY THE OFFICIAL BLENDED FORECAST DEPICTS WELL-DEFINED TROUGHS NEAR THE CALIFORNIA COAST AND EXTENDING SOUTH FROM LABRADOR INTO THE WESTERN ATLANTIC... WHILE THE TROUGH OVER THE BERING SEA AND SOUTH OF THE ALEUTIANS IS FORECAST TO BE WEAKER TODAY. THE BLOCKING RIDGE OVER THE NORTH ATLANTIC SECTOR THAT EARLIER IN THE WEEK HAD BEEN PREDICTED TO BE CENTERED OVER GREENLAND IS NOW FORECAST TO WEAKEN AND MOVE EASTWARD TO THE GREENLAND SEA... WHILE THE MAIN FEATURE OF INTEREST TO U.S. WEATHER IS A STRONG RIDGE FORECAST OVER THE CENTRAL MISSISSIPPI VALLEY WITH THE ASSOCIATED POSITIVE HEIGHT ANOMALY CENTER FORECAST NEAR CHICAGO. FORECAST TOOLS BASED ON THIS PATTERN SHOW WARMTH OVER THE CENTRAL AND SOUTHEASTERN CONUS AND COOL CONDITIONS OVER MUCH OF THE WEST... WITH WET WEATHER OVER THE SOUTHWEST AND CENTRAL CONUS AND GENERALLY DRY IN THE EAST AND SOUTH... AS WELL AS THE PACIFIC NORTHWEST. ABOVE NORMAL TEMPERATURES AND PRECIPITATION ARE ALSO LIKELY FOR MOST OF ALASKA WITH ABOVE NORMAL HEIGHTS AND A GENERALLY ANOMALOUS SOUTHERLY FLOW OF RELATIVELY MILD MARITIME AIR INTO THE STATE... ALTHOUGH THE SOUTHERN PANHANDLE COULD BE DRY UNDER THE INFLUENCE OF THE RIDGE APPROACHING THE BRITISH COLUMBIA COAST. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...5 PERCENT OF YESTERDAY'S OPERATIONAL 12Z GFS CENTERED ON DAY 7...5 PERCENT OF YESTERDAY'S OPERATIONAL 18Z GFS CENTERED ON DAY 7...30 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...30 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...AND 25 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: 0Z AND 6Z GFS ENSEMBLE MEANS (TIED) FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE... 4 ON A SCALE OF 1 TO 5 DUE TO GOOD MODEL AGREEMENT AND DAY-TO-DAY CONSISTENCY ON A FAIRLY AMPLIFIED PATTERN IN THE VICINITY OF THE CONUS AND REASONABLE CONSISTENCY AMONG THE SPECIFICATION TOOLS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHTS... CALIBRATED AND UNCALIBRATED TEMPERATURES FROM THE 0Z GFS ENSEMBLE MEAN... AND THE CDC CALIBRATED FORECAST. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET SPECIFICATION... THE CPC AUTO FORECAST... THE CPC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES... THE CDC CALIBRATED FORECAST... AND ANALOG SPECIFICATIONS FROM THE OFFICIAL FORECAST AND THE MODELS.THE EMC CALIBRARED PERCENTAGES WERE NOT AVAILABLE IN TIME. 8-14 DAY OUTLOOK FOR OCT 07 - 13 2006: FOR WEEK 2... THERE IS NOTICEABLE UNCERTAINTY IN TODAYS MODELS AS THE TREND TOWARDS A POSITIVE PHASE OF THE PNA PATTERN THAT SEEMED TO BE WELL-INDICATED YESTERDAY HAS NOW BEEN REVERSED WITH MANY MODELS PREDICTING A FULL LATITUDE TROUGH OVER WESTERN NORTH AMERICA... WITH A SLIGHT RETROGRESSION AND WEAKENING OF THE RIDGE OVER THE EASTERN GULF OF ALASKA. ANOTHER DISTURBING TREND IS THAT THE OPERATIONAL 0Z AND 6Z RUNS ARE QUITE DIFFERENT FROM THEIR RESPECTIVE ENSEMBLE MEANS... ESPECIALLY AT HIGH LATITUDES. THE 500-HPA PATTERN AS DEPICTED IN THE OFFICIAL BLENDED FORECAST SHOWS A TROUGH FROM THE WESTERN BERING SEA ACROSS THE WESTERN ALEUTIANS... A RIDGE OVER THE NORTHERN GULF OF ALASKA AND ALASKA... AND A DEEPENING TROUGH OVER THE CANADIAN MARITIMES. INSTEAD OF WEAKENING AND RETROGRADING AS IN PREVIOUS DAYS MODEL FORECASTS... TODAY THE RIDGE PREDICTED OVER THE CENTRAL MISSISSIPPI VALLEY DURING THE 6-10 DAY PERIOD IS FORECAST TO WEAKEN ONLY SLIGHTLY AND PROGRESS TO THE OHIO VALLEY. THE BLOCKING RIDGE OVER THE NORTH ATLANTIC IS FORECAST TO REDEVELOP WITH A POSITIVE ANOMALY CENTER WEST OF THE BRITISH ISLES. PREDICTED MIDDLE TROPOSPHERIC HEIGHT ANOMALIES AND FORECAST TOOLS FOR TEMPERATURE AND PRECIPITATION BASED ON THE PATTERN ARE REASONABLY DEFINITIVE OVER MUCH OF THE CONUS... BUT THERE IS A WIDE DISPARITY OF FORECAST INDICATIONS FROM THE TOOLS BASED ON THE INDIVIDUAL MODELS. MOST OF ALASKA IS EXPECTED TO REMAIN GENERALLY MILD... WITH WET CONDITIONS IN THE SOUTH AND WEST AND DRY IN THE EAST AND THE PANHANDLE. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...15 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...15 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...10 PERCENT OF YESTERDAY'S 18Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...AND 40 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS SOMEWHAT BELOW AVERAGE TODAY... 2 ON A SCALE OF 1 TO 5 DUE TO A REVERSAL IN SOME OF THE TRENDS THAT SEEMED TO BE DEVELOPING IN THE FORECASTS OVER THE PAST COUPLE OF DAYS... AND LESS AGREEMENT AMONG THE MODELS WITH SOME OF THE OPERATIONAL RUNS HAVING A VERY DIFFERENT PHASE THAN THE CORRESPONDING ENSEMBLE MEANS. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... KLEIN... NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHTS... AND THE CDC CALIBRATED FORECAST. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE CPC AUTO FORECAST... THE CPC AND EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES... THE CDC AND EMC CALIBRATED FORECAST... AND ANALOG SPECIFICATIONS FROM THE OFFICIAL FORECAST AND THE MODELS. FORECASTER: A. J. WAGNER 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 OCTOBER 19. AN UPDATED MONTHLY FORECAST FOR OCTOBER WILL ALSO BE ISSUED ON SEPTEMBER 30. 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: 19791011 - 19871010 - 19711010 - 19910926 - 19660929 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: 19791011 - 19660929 - 19871010 - 19711010 - 19930908 6 to 10 day Outlook Table OUTLOOK FOR OCT 05 - 09, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N B OREGON B B NRN CALIF B N SRN CALIF B A IDAHO B N NEVADA B A W MONTANA B N E MONTANA B A WYOMING N A UTAH N A ARIZONA B A COLORADO A A NEW MEXICO A A N DAKOTA N A S DAKOTA A A NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A N S TEXAS A B W TEXAS A A MINNESOTA A A IOWA A A MISSOURI A A ARKANSAS A N LOUISIANA A B WISCONSIN A A ILLINOIS A A MISSISSIPPI A B MICHIGAN A N INDIANA A N OHIO A B KENTUCKY A B TENNESSEE A B ALABAMA A B NEW YORK N B VERMONT N B NEW HAMP N B MAINE B N MASS N B CONN N B RHODE IS N B PENN N B NEW JERSEY N B W VIRGINIA A B MARYLAND N B DELAWARE N B VIRGINIA N B N CAROLINA N B S CAROLINA A B GEORGIA A B FL PNHDL A B FL PENIN A B AK N SLOPE A N AK ALEUTIAN A A AK WESTERN A A AK INT BSN A N AK S INT A A AK SO COAST A A AK PNHDL N B 8 to 14 day Outlook Table OUTLOOK FOR OCT 07 - 13, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N B OREGON N B NRN CALIF N B SRN CALIF B N IDAHO N N NEVADA B N W MONTANA B A E MONTANA B A WYOMING B A UTAH N A ARIZONA B A COLORADO N A NEW MEXICO N A N DAKOTA B A S DAKOTA B A NEBRASKA N A KANSAS N A OKLAHOMA A A N TEXAS A A S TEXAS A N W TEXAS N A MINNESOTA B A IOWA N A MISSOURI N A ARKANSAS A A LOUISIANA A N WISCONSIN N A ILLINOIS N A MISSISSIPPI A N MICHIGAN N A INDIANA N N OHIO N N KENTUCKY N N TENNESSEE A N ALABAMA A N NEW YORK B N VERMONT B B NEW HAMP B B MAINE B N MASS B B CONN N B RHODE IS N B PENN N B NEW JERSEY N B W VIRGINIA N B MARYLAND N B DELAWARE N B 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 A N AK ALEUTIAN A A AK WESTERN A A AK INT BSN A N AK S INT A A AK SO COAST A A 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. $$