PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EST THU NOV 15 2007 6-10 DAY OUTLOOK VALID FOR NOV 21 - 25 2007 TODAYS MODELS ARE IN GOOD AGREEMENT ON THE LARGE-SCALE FEATURES OF THE 500-HPA CIRCULATION OVER NORTH AMERICA. THE MODELS CONTINUE TO FORECAST A STRONG RIDGE OVER THE GULF OF ALASKA WITH A DOWNSTREAM TROUGH DIGGING INTO THE WESTERN CONUS. THERE IS CONSIDERABLE VARIABILITY AMONG THE MODELS ON HOW SHARP THE DOWNSTREAM TROUGH WILL BE. THE HIGH RESOLUTION ECMWF DIGS THE TROUGH INTO THE SOUTHWEST U.S. AND KEEPS SOME RIDGING IN THE SOUTHEAST... WHILE THE GFS ENSEMBLES FAVOR A MORE ROUNDED TROUGH THAT RESULTS IN A BROAD AREA OF BELOW NORMAL 500-HPA HEIGHTS OVER MUCH OF THE CONUS... EXCEPT FOR THE PACIFIC NORTHWEST AND THE EAST COAST. IN GENERAL MODELS HAVE BEEN TRENDING TOWARDS THE WESTWARD SOLUTIONS... HOWEVER A LOOK AHEAD TO THE 8-14 DAY MEANS SUGGESTS THAT THE TROUGH WILL BE PROGRESSIVE... SO THE SOLUTION OF GFS ENSEMBLES IS PERFERRED. TEMPERATURES ARE EXPECTED TO BE SIGNIFICANTLY BELOW AVERAGE OVER THE WESTERN CONUS... WITH BELOW NORMAL TEMPERATURES SPREADING EASTWARD THROUGH THE PERIOD... MAKING MEAN TEMPERATURES IN THE EASTERN U.S. QUITE UNCERTAIN. THE MEAN STORM TRACK OVER THE CENTRAL AND EASTERN CONUS IS SIMILARLY UNCERTAIN... DEPENDING ON THE POSITION OF THE WESTERN TROUGH... ALTHOUGH IN GENERAL A LARGE AREA OF THE CENTRAL AND EASTERN CONUS IS AT INCREASED RISK OF ABOVE MEDIAN PRECIPITATION ASSOCIATED WITH SOUTHWESTERLY FLOW ALOFT ENABLING MOISTURE INFLOW FROM THE GULF OF MEXICO. THE RIDGE OVER THE GULF OF ALASKA IS EXPECTED TO DIVERT THE PACIFIC JET NORTHWARD OF ITS NORMAL POSITION... RESULTING IN BELOW MEDIAN PRECIPITATION ALONG THE WEST COAST AND THE PACIFIC NORTHWEST... TRANSITIONING IN THE ALASKAN PANHANDLE... AND ABOVE NORMAL PRECIPITATION SOUTHERN ALASKA. TEMPERATURES IN MOST OF ALASKA ARE EXPECTED TO AVERAGE ABOVE NORMAL. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...20 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 8...20 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...AND 40 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8. MODEL(S) OF THE DAY: GFS SUPERENSEMBLE MEAN. FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5... WITH CONFIDENCE HIGH OVER THE WEST... BUT LOW IN THE EASTERN U.S. DUE TO MODEL DIFFICULTIES IN PREDICTING THE MEAN STORM TRACK OVER THE EAST. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... KLEIN TEMPERATURE PROBABILITIES FROM THE GFS AND ECMWF ENSEMBLES... AND THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE OUTLOOK. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE CPC AUTO FORECAST... SPECIFICATIONS BASED ON THE CDC REFORECASTS AND ANALOGS OF THE OFFICIAL BLEND AND THE VARIOUS MODELS. 8-14 DAY OUTLOOK FOR NOV 23 - 29 2007: THE MODELS PREDICT THAT THE STRONG RIDGE WILL PERSIST OVER THE GULF OF ALASKA BETWEEN THE 6-10 AND 8-14 DAY PERIOD. THE MEAN TROUGH DOWNSTREAM OF THIS RIDGE IS EXPECTED TO BE QUITE BROAD... WITH 500-HPA HEIGHTS BELOW NORMAL FROM THE GREAT BASIN EASTWARD TO THE ATLANTIC SEABOARD. THE MAIN TROUGH AXIS IS EXPECTED OVER THE MISSISSIPPI VALLEY... SUGGESTING BELOW NORMAL TEMPERATURES OVER MOST OF THE COUNTRY EXCEPT FOR SOME NEAR NORMAL TEMPERATURES ALONG THE WEST COAST AND ABOVE NORMAL TEMPERATURES IN THE FLORIDA PENINSULA. THE EASTERN SEABOARD IS AT INCREASED RISK OF WET CONDITIONS AHEAD OF THE TROUGH AXIS. ABOVE MEDIAN PRECIPITATION IS INDICATED OVER THE NORTHERN ROCKIES BY ANALOGS... DUE TO THE CHANCE OF UPSLOPE PRECIPITATION. BELOW MEDIAN PRECIPITATION AMOUNTS ARE EXPECTED BEHIND THE MEAN TROUGH AXIS FROM TEXAS... THE SOUTHWESTERN CONUS... UP THE WEST COAST TO EASTERN ALASKA. ABOVE MEDIAN PRECIPITATION IS EXPECTED FOR WESTERN ALASKA WHICH IS FORECAST TO BE TO THE WEST OF THE MEAN RIDGE AXIS. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...20 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 40 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... THE CDC REFORECAST TEMPERATURES... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... AND THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE OUTLOOK. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE THE CPC AUTO FORECAST... CDC REFORECAST PRECIPITATION... AND ANALOGS OF THE OFFICIAL BLEND AND THE VARIOUS MODELS. FORECASTER: D. UNGER 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 DECEMBER 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: 19911117 - 19771114 - 19601119 - 19611111 - 19941026 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: 19771113 - 19611109 - 19911116 - 19601118 - 19551025 6 to 10 day Outlook Table OUTLOOK FOR NOV 21 - 25, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B B OREGON B B NRN CALIF B B SRN CALIF B B IDAHO B B NEVADA B B W MONTANA B N E MONTANA B A WYOMING B A UTAH B B ARIZONA B B COLORADO B A NEW MEXICO B N N DAKOTA B A S DAKOTA B A NEBRASKA B A KANSAS B A OKLAHOMA B A N TEXAS B A S TEXAS B A W TEXAS B A MINNESOTA B A IOWA B A MISSOURI B A ARKANSAS B A LOUISIANA B A WISCONSIN B A ILLINOIS B A MISSISSIPPI N A MICHIGAN B A INDIANA B A OHIO N A KENTUCKY N A TENNESSEE N A ALABAMA N A NEW YORK N A VERMONT N A NEW HAMP N A MAINE N N MASS N A CONN N A RHODE IS N A PENN N A NEW JERSEY N A W VIRGINIA N A MARYLAND N A DELAWARE N A VIRGINIA N A N CAROLINA A A S CAROLINA A A GEORGIA A A FL PNHDL A N FL PENIN A B AK N SLOPE A N AK ALEUTIAN A A AK WESTERN A A AK INT BSN A A AK S INT A A AK SO COAST A A AK PNHDL N N 8 to 14 day Outlook Table OUTLOOK FOR NOV 23 - 29, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B B OREGON B B NRN CALIF N B SRN CALIF N B IDAHO B B NEVADA B B W MONTANA B A E MONTANA B A WYOMING B A UTAH B B ARIZONA B B COLORADO B N NEW MEXICO B B N DAKOTA B B S DAKOTA B N NEBRASKA B N KANSAS B N OKLAHOMA B N N TEXAS B B S TEXAS B N W TEXAS B B MINNESOTA B B IOWA B B MISSOURI B B ARKANSAS B N LOUISIANA B N WISCONSIN B B ILLINOIS B B MISSISSIPPI B N MICHIGAN B B INDIANA B B OHIO B N KENTUCKY B N TENNESSEE B N ALABAMA B N NEW YORK B A VERMONT B A NEW HAMP B A MAINE B A MASS B A CONN B A RHODE IS B A PENN B A NEW JERSEY B A W VIRGINIA B N MARYLAND N A DELAWARE N A VIRGINIA N A N CAROLINA N A S CAROLINA N A GEORGIA N A FL PNHDL N A FL PENIN A N AK N SLOPE A N AK ALEUTIAN A A AK WESTERN A A AK INT BSN A N AK S INT A N 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. $$