PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT FRI AUG 25 2006 6-10 DAY OUTLOOK VALID FOR AUG 31 - SEP 04, 2006 TODAYS ENSEMBLE MEANS AND DETERMINISTIC SOLUTIONS ARE IN REASONABLE AGREEMENT ON THE PREDICTED FEATURES OF THE 500-HPA HEIGHT PATTERN OVER THE PACIFIC - NORTH AMERICA REGION, THOUGH THERE ARE NOTICEABLE DIFFERENCES. THE UNDERLYING THEME CONTINUES TO EMPHASIZE A MEAN TROUGH NEAR THE COAST OF THE PACIFIC NORTHWEST, A RIDGE OVER THE CENTRAL U.S., AND A TROUGH JUST OFF THE ATLANTIC SEABOARD, IN ADDITION TO A TROUGH OVER ALASKA AND THE ADJACENT GULF. THE ANCHORING CIRCULATION FEATURE FOR THE NORTH AMERICAN WAVETRAIN IS A STRONG BLOCK PREDICTED BETWEEN THE WESTERN ALEUTIANS AND KAMCHATKA. SOME OF THE VARIATIONS ON THIS THEME INCLUDE SIGNIFICANTLY MORE AMPLIFIED LONGWAVE FEATURES OVER THE CONUS AND SOUTHERN CANADA (OPERATIONAL 0Z AND 6Z GFS SOLUTIONS), AND A SOMEWHAT FASTER SCENARIO INDICATED BY YESTERDAYS 12Z ECMWF WHICH ADVANCES THE PACIFIC NORTHWEST TROUGH TO NEAR THE NORTHERN ROCKIES AND THE CENTRAL U.S. RIDGE TO THE GREAT LAKES AREA. THE OPERATIONAL 0Z AND 6Z GFS SOLUTIONS ARE SIMILAR TO YESTERDAYS 12Z ECMWF SOLUTION IN THAT THEY ALSO PROGRESS THE RIDGE EASTWARD TO THE GREAT LAKES REGION. THE CANADIAN ENSEMBLE MEAN DEPICTS A WEAK TROUGH ACROSS THE SOUTHEAST, WHERE THERE IS ALSO A PROMINENT BREAK IN THE SUBTROPICAL RIDGE. FINALLY, IN THE EASTERN CARIBBEAN, A TROPICAL DEPRESSION HAS FORMED AND IS EXPECTED TO INTENSIFY OVER THE NEXT FEW DAYS. IF THE PRELIMINARY ESTIMATES FROM THE NATIONAL HURRICANE CENTER ARE CORRECT, THIS DEPRESSION WOULD INTENSIFY INTO A HURRICANE AND MOVE INTO THE SOUTHERN GULF OF MEXICO BY EARLY NEXT WEEK. THEREFORE, THIS STORM COULD HAVE A SIGNIFICANT INFLUENCE ON THE 6-10 DAY PRECIPITATION FORECAST FOR THE GULF COAST STATES, AND NEEDS TO BE CLOSELY MONITORED. 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...20 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 50 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: ECMWF ENSEMBLE AVERAGE FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS NEAR AVERAGE ... 3 ON A SCALE OF 1 TO 5... DUE TO REASONS MENTIONED EARLIER. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND. IT IS ALSO BASED ON SUBJECTIVE REVIEW OF THE DAILY 6Z GFS MAPS OF THICKNESS ADVECTION AND STORM TRACKS. THE CPC AUTO TEMPERATURE FORECAST AND THE CDC TEMPERATURE FORECAST WERE ALSO USED TODAY. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND... THE EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLE... AND ON A SUBJECTIVE REVIEW OF GENERAL STORM TRACKS AND PRECIPITATION AREAS PREDICTED BY THE 6Z GFS MODEL. THE CPC AUTO PRECIPITATION FORECAST AND THE CDC PRECIPITATION FORECAST WERE ALSO USED TODAY. 8-14 DAY OUTLOOK FOR SEP 02 - 08 2006: DURING WEEK 2 THE MODELS ARE IN DECENT AGREEMENT, THOUGH AGAIN THERE ARE ENOUGH DIFFERENCES BETWEEN THEM TO DIMINISH THE CONFIDENCE LEVEL TO NEAR NORMAL. AS IS COMMONLY THE CASE IN SUMMER, THE MODERATE AND STRONG HEIGHT ANOMALIES ARE LOCATED NEAR AND POLEWARD OF 50N LATITUDE, WITH ONLY WEAK ANOMALIES ACROSS THE CONUS. FOR THE FIRST TIME THIS WEEK, THE SINGLE 0Z GFS RUN IS SHOWING AN EASTWARD DISPLACED WAVETRAIN ACROSS NORTH AMERICA BY ABOUT 10 DEGREES FROM THE MODEL CONSENSUS POSITION. THIS BRINGS THE WEST COAST TROUGH WELL INTO THE INTERIOR OF THE PACIFIC NORTHWEST... AND THERE HAS BEEN CONSIDERABLE UNCERTAINTY ALL WEEK AS TO WHETHER OR NOT THIS TROUGH WOULD REMAIN ALONG THE COAST OR MOVE WELL INLAND. THE 0Z GFS RUN ALSO HAS THE MEAN POSITION OF THE ALASKA TROUGH AXIS FURTHER EAST, CLOSER TO THE PANHANDLE REGION. THE CANADIAN ENSEMBLE MEAN SOLUTION PREDICTS A WEAK TROUGH ACROSS THE EASTERN U.S., WITH WEAK NEGATIVE HEIGHT DEPARTURES FROM THE GREAT LAKES REGION TO THE TENNESSEE VALLEY, WHICH SETS THIS MODEL RUN APART FROM THE OTHERS. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...20 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...50 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 10 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS AVERAGE TODAY... 3 ON A SCALE OF 1 TO 5... DUE TO REASONABLE MODEL AGREEMENT, BUT OFFSET BY CONTINUING WEAK HEIGHT ANOMALY PATTERNS. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... NEURAL NET... AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND. THE CPC AUTO TEMPERATURE FORECAST AND THE CDC REFORECAST TEMPERATURE TOOL WERE ALSO USED. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND... AND THE EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLE. TODAYS 12Z GFS WAS ALSO CONSULTED FOR GENERAL PRECIPITATION AREAS AND MEAN STORM TRACKS. THE CPC AUTO FORECAST AND THE CDC REFORECAST TOOL WERE ALSO USED TODAY. FORECASTER: ARTUSA 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 21. 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: 19600807 - 19820901 - 19970815 - 19540827 - 19870903 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: 19600807 - 19820901 - 19630807 - 19580907 - 19540827 6 to 10 day Outlook Table OUTLOOK FOR AUG 31 - SEP 04, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B B OREGON B B NRN CALIF N B SRN CALIF N B IDAHO N N NEVADA N B W MONTANA N N E MONTANA A A WYOMING A A UTAH A B ARIZONA A B COLORADO A A NEW MEXICO A N N DAKOTA A A S DAKOTA A A NEBRASKA A N KANSAS A N OKLAHOMA N N N TEXAS N N S TEXAS N N W TEXAS N N MINNESOTA A N IOWA A N MISSOURI A B ARKANSAS A N LOUISIANA N A WISCONSIN A B ILLINOIS A B MISSISSIPPI N A MICHIGAN A B INDIANA A B OHIO N B KENTUCKY A B TENNESSEE N N ALABAMA N A NEW YORK N B VERMONT N B NEW HAMP N B MAINE N 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 B B N CAROLINA B N S CAROLINA N N GEORGIA N A FL PNHDL N A FL PENIN N N AK N SLOPE B N AK ALEUTIAN A B AK WESTERN N B AK INT BSN B B AK S INT N B AK SO COAST N B AK PNHDL B N 8 to 14 day Outlook Table OUTLOOK FOR SEP 02 - 08, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N N NRN CALIF N B SRN CALIF A B IDAHO A B NEVADA A B W MONTANA A N E MONTANA A N WYOMING A N UTAH A B ARIZONA A B COLORADO A N NEW MEXICO A N N DAKOTA A A S DAKOTA A A NEBRASKA A A KANSAS N A OKLAHOMA N N N TEXAS N N S TEXAS N N W TEXAS N N MINNESOTA A A IOWA A N MISSOURI A N ARKANSAS N N LOUISIANA N N WISCONSIN A N ILLINOIS A B MISSISSIPPI N N MICHIGAN A N INDIANA A B OHIO A B KENTUCKY A B TENNESSEE A B ALABAMA N N NEW YORK A B VERMONT A B NEW HAMP A B MAINE A B MASS A B CONN A B RHODE IS A B PENN A B NEW JERSEY A B W VIRGINIA A B MARYLAND A B DELAWARE A B VIRGINIA A B N CAROLINA A B S CAROLINA A B GEORGIA N N FL PNHDL N N FL PENIN N N AK N SLOPE B N AK ALEUTIAN A B AK WESTERN N B AK INT BSN B N AK S INT B B AK SO COAST N B AK PNHDL B 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. $$