PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT MON SEP 17 2007 6-10 DAY OUTLOOK VALID FOR SEP 23 - 27 2007 TODAYS ENSEMBLE MEAN FORECASTS ARE IN GOOD AGREEMENT ON THE MEAN 500-HPA FLOW PATTERN EXPECTED OVER NORTH AMERICA. HOWEVER... OPERATIONAL RUNS OF THE 0Z GFS AND 0Z ECMWF DEPICT SLIGHTLY LESS PROGRESSIVE FLOW WITH RESPECT TO A TROUGH ALONG THE WEST COAST. THE ANOMALOUS 500-HPA CLOSED LOW IN THE NORTHEAST PACIFIC RESPRESENTED BY THE OPERATIONAL RUN OF THE 6Z GFS IS DISCOUNTED AS AN OUTLIER. THE OFFICIAL BLENDED 500-HPA HEIGHT FIELD INDICATES A BROAD TROUGH ALONG THE WEST COAST AND A LARGE SCALE RIDGE OVER THE EAST. POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER THE NORTH-CENTRAL PACIFIC AND EASTERN NORTH AMERICA WITH NEGATIVE 500-HPA HEIGHT ANOMALIES ACROS WESTERN NORTH AMERICA. TEMPERATURE TOOLS ARE IN EXCELLENT AGREEMENT THAT BELOW NORMAL TEMPERATURES WILL AFFECT THE WEST COAST WHILE A LARGE AREA OF ABOVE NORMAL TEMPERATURES WILL EXTEND FROM THE HIGH PLAINS TO THE EAST COAST. TELECONNECTIONS FROM THE POSITIVE 500-HPA HEIGHT ANOMALY GREATER THAN 120 METERS IN SOUTHEAST CANADA OFFERS ADDITIONAL SUPPORT FOR THE TEMPERATURE FORECAST ACROSS THE CONUS. THE GREATEST POSITIVE TEMPERATURE ANOMALIES WILL LIKELY BE LOCATED ACROSS THE GREAT LAKES. ELSEWHERE... ACROSS ALASKA... ABOVE NORMAL TEMPERATURES ARE FORECAST. BY THE BEGINNING OF THE OUTLOOK PERIOD... A DEEP CLOSED 500-HPA LOW ALONG THE WEST COAST WILL LIKELY OPEN AND TRACK ACROSS THE INTERMOUNTAIN WEST. AS THIS SHORTWAVE TROUGH INTERACTS WITH MOISTURE FROM THE EAST PACIFIC... ABOVE NORMAL PRECIPITATION IS EXPECTED FOR THE NORTHERN AND CENTRAL ROCKIES. MOIST PACIFIC FLOW SHOULD RESULT IN ABOVE NORMAL PRECIPITATION FOR THE PACIFIC NORTHWEST. EARLY IN THE PERIOD... ALL OPERATIONAL MODELS ARE SHOWING A TROPICAL SYSTEM MOVING INTO THE WESTERN GULF REGION. THEREFORE... RELATIVELY HIGH PROBABILITIES FOR ABOVE NORMAL RAINFALL ARE FORECAST FOR TEXAS... OKLAHOMA... AND LOUISIANA. THE GULF MOISTURE COULD GET ENTRAINED INTO FRONTS CROSSING THE PLAINS WHERE ABOVE NORMAL RAINFALL IS ALSO FORECAST. ACROSS THE EASTERN CONUS... A RIDGE ALOFT WILL RESULT IN BELOW NORMAL PRECIPITATION. FAST FLOW ACROSS THE NORTH PACIFIC SHOULD RESULT IN ABOVE NORMAL PRECIPITATION FOR THE ALEUTIANS AND WESTERN ALASKA. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...15 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...30 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...AND 20 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: GFS SUPERENSEMBLE MEAN FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE... 4 ON A SCALE OF 1 TO 5... DUE TO AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS AND TEMPERATURE AND PRECIPITATION TOOLS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... ANALOG... AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND... THE CPC AUTO FORECAST... THE CDC TEMPERATURE TOOL... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURES... 2-METER UNCALIBRATED AND CALIBRATED TEMPERATURES... AND TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 45N 80W. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODEL HEIGHT FIELDS... THE CPC AUTO FORECAST... THE CDC PRECIPITATION TOOL... CPC CALIBRATED PRECIPITATION FROM THE GFS-BASED MODELS... INSPECTION OF THE DAILY PRECIPITATION FORECASTS FROM THE VARIOUS MODELS... AND TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 45N 80W. 8-14 DAY OUTLOOK FOR SEP 25 - OCT 01, 2007: FOR WEEK 2 THE GFS ENSEMBLE MEAN SOLUTIONS DEAMPLIFY THE FLOW PATTERN MORE THAN THEIR RESPECTIVE OPERATIONAL RUNS AND THE 0Z CANADIAN ENSEMBLE MEAN. ALL MODEL SOLUTIONS STRENGTHEN A RIDGE IN THE NORTH-CENTRAL PACIFIC WHICH SHOULD MAINTAIN A MORE AMPLIFIED TROUGH ALONG THE WEST COAST. TELECONNECTIONS ON THE POSITIVE 500-HPA HEIGHT ANOMALY IN THE NORTH-CENTRAL PACIFIC SUPPORT A DEEPER TROUGH ALONG THE WEST COAST. FOR THE CENTRAL AND EASTERN CONUS... NEARLY ZONAL FLOW IS EXPECTED WITH SLIGHTLY POSITIVE 500-HPA HEIGHT ANOMALIES. A TROUGH WILL LIKELY MAINTAIN BELOW NORMAL TEMPERATURES FOR THE WEST COAST WHILE NEAR TO ABOVE NORMAL TEMPERATURES ARE FORECAST FOR THE REMAINDER OF THE CONUS AND ALASKA. THE PRECIPITATION FORECAST FOR WEEK 2 CLOSELY RESEMBLES THE 6-10 DAY PRECIPITATION FORECAST WITH LOWER PROBABILITIES. A SERIES OF NORTH PACIFIC STORMS WILL RESULT IN ABOVE NORMAL PRECIPITATION FOR MUCH OF ALASKA... THE PACIFIC NORTHWEST... AND NORTHERN CALIFORNIA. BELOW NORMAL PRECIPITATION SHOULD CONTINUE FOR THE MID-ATLANTIC AND NORTHEAST. THE GREATEST UNCERTAINTY IN THE PRECIPITATION FORECAST EXISTS ACROSS THE PLAINS AND MISSISSIPPI VALLEY. DESPITE THAT UNCERTAINTY... ABOVE NORMAL PRECIPITATION IS FORECAST FOR THE PLAINS AND MISSISSIPPI VALLEY WHERE SHORTWAVE TROUGHS CROSSING THE PLAINS MAY INTERACT WITH ABUNDANT GULF MOISTURE. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 30 PERCENT OF TODAY'S OPERATIONAL 0Z 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...20 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 ABOVE AVERAGE... 4 ON A SCALE OF 1 TO 5... DUE TO GOOD MODEL AGREEMENT. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... ANALOG... AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND... THE CPC AUTO FORECAST... THE CDC TEMPERATURE TOOL... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURES... AND TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER AT 45N 175W. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODEL HEIGHT FIELDS... CPC CALIBRATED PRECIPITATION FROM THE GFS ENSEMBLE MEANS... THE CPC AUTO FORECAST... AND THE CDC PRECIPITATION TOOL. FORECASTER: PUGH 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: 19640926 - 19931001 - 19560916 - 19930909 - 19930903 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: 19640926 - 19930930 - 19560915 - 19930908 - 19930903 6 to 10 day Outlook Table OUTLOOK FOR SEP 23 - 27, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON B A NRN CALIF B A SRN CALIF B B IDAHO N A NEVADA N A W MONTANA N A E MONTANA A A WYOMING A A UTAH N A ARIZONA N B COLORADO A A NEW MEXICO A N N DAKOTA A A S DAKOTA A 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 A WISCONSIN A A ILLINOIS A A MISSISSIPPI A A MICHIGAN A A INDIANA A N OHIO A N KENTUCKY A N TENNESSEE A N ALABAMA A 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 A B FL PNHDL A N FL PENIN A N 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 SEP 25 - OCT 01, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON N A NRN CALIF B A SRN CALIF B B IDAHO N A NEVADA N N W MONTANA N A E MONTANA A A WYOMING A A UTAH N B ARIZONA N B COLORADO A B NEW MEXICO N B N DAKOTA A A S DAKOTA A A NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A A S TEXAS A A W TEXAS A N MINNESOTA A A IOWA A A MISSOURI A A ARKANSAS A A LOUISIANA A A WISCONSIN A A ILLINOIS A A MISSISSIPPI A A MICHIGAN A A INDIANA A A OHIO A N KENTUCKY A N TENNESSEE A N ALABAMA A 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 N S CAROLINA A N GEORGIA A N FL PNHDL A N 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 A AK SO COAST A A AK PNHDL A N 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. $$