PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT WED AUG 27 2008 6-10 DAY OUTLOOK VALID FOR SEP 02 - 06 2008 THE ENSEMBLE MEAN SOLUTIONS CONTINUE TO BE IN REASONABLY GOOD AGREEMENT FOR THE EXPECTED 500-HPA FLOW PATTERN OVER THE FORECAST DOMAIN. THE CANADIAN ENSEMBLE MEAN IS IN BETTER AGREEMENT WITH THE OTHER MODEL SOLUTIONS TODAY THAN IN PREVIOUS DAYS. THE PRIMARY CHANGES TODAY COMPARED TO YESTERDAY ARE THE CONSIDERABLE DIFFERENCES IN THE 00Z AND 06Z OPERATIONAL RUNS. THESE MODEL SOLUTIONS VARY CONSIDERABLY FROM THEIR ENSEMBLE MEAN SOLUTIONS. THERE IS SOME RUN TO RUN CONSISTENCY IN THESE SOLUTIONS BUT AT THE CURRENT TIME THESE SOLUTIONS DID NOT RECEIVE SIGNIFICANT WEIGHT IN THE OFFICIAL BLEND FORECAST WHICH INCLUDES MAINLY CONTRIBUTIONS FROM THE GFS SUPERENSEMBLE AND THE 00Z AND 06Z GFS ENSEMBLE MEANS. BASED ON THE ABOVE APPROACH, A TROUGH IS EXPECTED TO SITUATE ITSELF ALONG THE US WEST COAST WITH A RIDGE ACROSS THE EASTERN TWO-THIRDS OF THE COUNTRY. A CUTOFF LOW IS NOW EVIDENT IN THE OFFICAL BLEND AS THE GFS ENSEMBLE MEAN FORECASTS ARE IN CLOSER AGREEMENT TO THAT OF YESTERDA'S EUROPEAN. AS A RESULT OF THIS FORECAST PATTERN, ABOVE-AVERAGE TEMPERATURES AND BELOW-MEDIAN PRECIPITATION ARE EXPECTED TO PREVAIL ACROSS PARTS OF THE NORTH-CENTRAL US AND GREAT LAKES DUE TO THE RIDGE AND ABOVE-AVERAGE HEIGHTS IN THIS AREA. DUE TO INCREASING UNCERTAINTY, THE SPATIAL EXTENT AND PROBABILITIES FOR THESE AREAS OF ANOMALOUS TEMPERATURES AND PRECIPITATION HAVE BEEN DECREASED. FAVORABLE ORIENTATION OF SUB-TROPICAL RIDGING ACROSS THE ATLANTIC BASIN WILL ALLOW NUMEROUS TROPICAL DISTURBANCES AND CONTINUED AMPLE MOISTURE FLOW TO IMPACT THE GULF COAST WITH ABOVE-MEDIAN PRECIPITATION DURING THE PERIOD. ALSO, THE TROUGH ALONG THE WEST COAST AND FLOW AROUND THE WESTERN PERIPHERY OF THE RIDGE LIKELY WILL LEAD TO AN INCREASING FLOW OF MOISTURE INTO THE PLAINS. MOREOVER, THE MEAN TROUGH ALONG THE WEST COAST SHOULD LEAD TO COOLER THAN AVERAGE TEMPERATURES ACROSS PARTS OF THE PACIFIC NORTHWEST AND THIS IS SUPPORTED BY MULTIPLE TOOLS. 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...20 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...AND 40 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8. MODEL(S) OF THE DAY: GFS SUPERENSEMBLE FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS NEAR-AVERAGE, 3 ON A SCALE OF 1 TO 5 DUE TO GENERALLY GOOD ENSEMNBLE MEAN AGREEMENT OFFSET BY CONSIDERABLE DIFFERENCES IN OPERATIONAL MODEL RUNS. THE EVOLUTION OF TROPICAL SYSTEMS ACROSS THE SOUTHERN TIER INCREASES THE UNCERTAINTY IN THIS REGION DURING THE PERIOD. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE PROBABILITY FORECASTS, THE KLEIN PROBABILITIES FROM THE VARIOUS ENSEMBLES INCLUDING THE SUPERENSEMBLE, AND UNCALIBRATED AND CALIBRATED TEMPERATURES FROM THE GFS ENSEMBLE MEAN. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND, THE AUTO PRECIPITATION FORECAST, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) PRECIPITATION PROBABILITY FORECASTS, AND NEURAL NET PROBABILITIES FROM THE VARIOUS ENSEMBLES. 8-14 DAY OUTLOOK FOR SEP 04 - 10 2008: FOR WEEK 2, THERE IS REASONABLY GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS WHICH GENERALLY REFLECT A DEAMPLIFIED 500-HPA PATTERN COMPARED TO THAT SHOWN FOR THE 6-10 DAY PERIOD. THE MAIN CIRCULATION FEATURES DURING THE 6-10 DAY PERIOD ARE ALSO EXPECTED TO BE IN PLACE DURING THIS FORECAST PERIOD. THERE WILL CONTINUE TO BE A TROUGH ALONG THE US WEST COAST WITH A RIDGE ACROSS THE EASTERN TWO-THIRDS OF THE COUNTRY. THE MAIN DIFFERENCE DURING THIS PERIOD FROM THE 6-10 DAY PERIOD IS SUBSTANTIALLY DECREASED AGREEMENT IN THE FORECAST TOOLS ESPECIALLY FOR PRECIPITATION. THEREFORE CONFIDENCE IS LOWER FOR THE WEEK 2 PERIOD. THE OFFICIAL BLEND IS BASED ON THE GFS SUPERENSEMBLE AND 00Z AND 06Z GFS ENSEMBLE MEAN SOLUTIONS. ABOVE-AVERAGE TEMPERATURES ARE EXPECTED TO CONTINUE ACROSS MUCH OF THE NORTH-CENTRAL US, GREAT LAKES AND NORTHEAST US DUE TO THE CONTINUATION OF THE RIDGE IN THIS AREA BUT DUE TO GREATER VARIABILITY IN THE FORECAST TOOLS, PROBABILITIES ARE SOMEWHAT LOWER. BELOW-AVERAGE TEMPERATURES ARE EXPECTED ACROSS PARTS OF THE SOUTHWEST US, AND ALONG THE GULF COAST ASSOCIATED WITH INCREASED CLOUD COVER AND MOISTURE FROM POSSIBLE TROPICAL CYCLONE ACTIVITY AND SLIGHTLY BELOW NORMAL HEIGHTS. ABOVE-MEDIAN PRECIPITATION IS EXPECTED TO CONTINUE DURING THIS PERIOD ACROSS THE GULF COAST AND ALSO INCLUDE PARTS OF THE SOUTHWEST US. THE AREA OF ABOVE-MEDIAN PRECIPITATION IS LIKELY TO BE ORIENTED SLIGHTLY NORTHWARD AND EASTWARD DURING THIS PERIOD COMPARED TO THE 6-10 DAY PERIOD AS THE UPPER-LEVEL TROUGH AND WESTERN EDGE OF THE SUBTROPICAL RIDGE SHOULD ALLOW SUBSTANTIAL MOISTURE TRANSPORT INTO THE CENTRAL PART OF THE COUNTRY. CONSIDERABLE DIFFERENCES EXIST IN THE FORECAST TOOLS ACROSS THE WESTERN AND NORTHEAST US. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 25 PERCENT OF YESTERDAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...25 PERCENT OF YESTERDAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...AND 50 PERCENT OF YESTERDAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS BELOW AVERAGE, 2 ON A SCALE OF 1 TO 5 DUE TO GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS OFFSET BY RELATIVELY POOR AGREEMENT AMONG THE FORECAST TOOLS AND LARGE UNCERTAINTY FOR FUTURE DEVELOPMENTS IN THE TROPICS. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE PROBABILITY FORECASTS, AND THE KLEIN PROBABILITIES FROM THE GFS ENSEMBLES MEAN FORECASTS INCLUDING THE SUPERENSEMBLE. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET SPECIFICATION FROM THE OFFICIAL BLEND AND VARIOUS ENSEMBLE MEAN FORECASTS, NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) PRECIPITATION PROBABILITY FORECASTS, THE AUTO BLEND PRECIPITATION FORECAST, AND THE CDC PRECIPITATION FORECAST. FORECASTER: GOTTSCHALCK 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 18 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. 6 to 10 day Outlook Table OUTLOOK FOR SEP 02 - 06, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B N NRN CALIF N N SRN CALIF N N IDAHO B N NEVADA B N W MONTANA B N E MONTANA N N WYOMING B N UTAH B N ARIZONA B N COLORADO B N NEW MEXICO B N N DAKOTA N N S DAKOTA N A NEBRASKA N A KANSAS N A OKLAHOMA N A N TEXAS B A S TEXAS B A W TEXAS B A MINNESOTA A N IOWA A N MISSOURI N A ARKANSAS N A LOUISIANA B A WISCONSIN A B ILLINOIS A N MISSISSIPPI B A MICHIGAN A B INDIANA A B OHIO A B KENTUCKY N N TENNESSEE N N ALABAMA B A NEW YORK N B VERMONT N N NEW HAMP N N MAINE N N MASS N N CONN N N RHODE IS N N PENN N B NEW JERSEY N N W VIRGINIA N B MARYLAND N N DELAWARE N N VIRGINIA N N N CAROLINA N N S CAROLINA B A GEORGIA B A FL PNHDL B A FL PENIN B A AK N SLOPE N N AK ALEUTIAN N A AK WESTERN N A AK INT BSN N N AK S INT N A AK SO COAST N A AK PNHDL N N 8 to 14 day Outlook Table OUTLOOK FOR SEP 04 - 10, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B N NRN CALIF N N SRN CALIF N N IDAHO B N NEVADA B N W MONTANA B N E MONTANA N N WYOMING B N UTAH B N ARIZONA B A COLORADO B A NEW MEXICO B A N DAKOTA N N S DAKOTA N A NEBRASKA N A KANSAS N A OKLAHOMA N A N TEXAS B A S TEXAS B A W TEXAS B A MINNESOTA A N IOWA A A MISSOURI N A ARKANSAS N A LOUISIANA B A WISCONSIN A N ILLINOIS A A MISSISSIPPI B A MICHIGAN A N INDIANA A N OHIO A N KENTUCKY N N TENNESSEE N N ALABAMA B A NEW YORK A N VERMONT N N NEW HAMP N N MAINE N N MASS N N CONN N N RHODE IS N N PENN A N NEW JERSEY N N W VIRGINIA A N MARYLAND N N DELAWARE N N VIRGINIA N N N CAROLINA N N S CAROLINA N N GEORGIA B A FL PNHDL B A FL PENIN B A AK N SLOPE N N AK ALEUTIAN B A AK WESTERN B A AK INT BSN N N AK S INT B A AK SO COAST B A 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. $$