PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT THU MAY 03 2007 6-10 DAY OUTLOOK VALID FOR MAY 09 - 13 2007 TODAYS MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT IN DEPICTING A CONSIDERABLY FLATTENED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA AND ADJACENT OCEANIC AREAS. YESTERDAYS OPERATIONAL 0Z AND 6Z GFS RUNS FOR THE WEEK 2 PERIOD SUGGESTED RISING 500-HPA HEIGHTS ACROSS THE WESTERN CONUS... AND THIS TREND CONTINUES WITH TODAYS 6-10 DAY MODEL RUNS. MOST SOLUTIONS NOW PREDICT A COAST-TO-COAST ZONAL RIDGE OVER THE LOWER 48 STATES... WITH ONE POSITIVE HEIGHT ANOMALY CENTER OVER THE NORTHEAST AND A NEW POSITIVE CENTER NOW SHOWING UP OVER THE CENTRAL ROCKIES. ANOTHER AREA OF ABOVE AVERAGE HEIGHTS IS FORECAST OVER THE NORTH-CENTRAL PACIFIC AND ADJOINING ALEUTIAN ARCHIPELAGO. THE TROUGH WHICH HAD BEEN PREDICTED OVER THE WESTERN CONUS DURING THE PAST FEW DAYS IS NOW FORECAST TO BE WELL OFF THE WEST COAST. THIS FEATURE CONTINUES NORTHEASTWARD TO THE ALASKA PANHANDLE... WITH ANOTHER TROUGH AND ASSOCIATED NEGATIVE HEIGHT ANOMALIES OVER NORTHWESTERN AND NORTHERN ALASKA. AN AREA OF MODESTLY BELOW NORMAL HEIGHTS CONTINUES TO BE PREDICTED ACROSS THE GULF OF MEXICO AND PORTIONS OF ADJACENT STATES. INCIDENTALLY ... YESTERDAYS OPERATIONAL 6Z GFS WAS THE MODEL THAT FIRST ANTICIPATED THE COAST TO COAST RIDGE AND THE EAST PACIFIC TROUGH THAT NEARLY ALL MODELS ARE GOING WITH TODAY. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 15 PERCENT OF TODAY'S OPERATIONAL 0Z 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...25 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 NEAR AVERAGE... 3 ON A SCALE OF 1 TO 5.... DUE TO CONVERGENCE OF NUMERICAL MODEL SOLUTIONS REGARDING THE NEW PATTERN OF A ZONAL RIDGE ACROSS THE LOWER 48 STATES... BUT OFFSET BY THIS UNUSUALLY LONG WAVELENGTH EXPECTED OVER THE CONUS AND THE ASSOCIATED TENDENCY FOR A MORE UNSTABLE AND TRANSIENT PATTERN. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN ... NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE GUIDANCE... THE CPC AUTO TEMPERATURE FORECAST... AND THE CDC TEMPERATURE TOOL. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO PRECIPITATION FORECAST... AND THE CDC PRECIPITATION TOOL. THE CPC CALIBRATED PRECIPITATION BASED ON THE GFS ENSEMBLES WAS ALSO CONSULTED. 8-14 DAY OUTLOOK FOR MAY 11 - 17 2007: TODAYS MODEL SOLUTIONS FOR WEEK 2 ARE GENERALLY SIMILAR TO WHAT THEY WERE YESTERDAY ACROSS THE NORTH AMERICAN CONTINENT AND NEARBY OCEAN AREAS... THOUGH THE OPERATIONAL 6Z GFS IS CONSIDERABLY DIFFERENT OVER THE CONUS. TODAYS OFFICIAL 6-10 DAY HEIGHT PROG DEPICTS A COAST-TO-COAST ZONAL RIDGE OVER THE CONUS WHICH HAS AN UNUSUALLY LONG WAVELENGTH FOR THIS TIME OF YEAR... AND IS THOUGHT TO BE TRANSIENT. THE ATMOSPHERE WILL LIKELY SETTLE THEREAFTER INTO A MORE MODAL PATTERN WITH THE TWIN ANOMALY CENTER RIDGE GIVING WAY TO A SINGLE POSITIVE ANOMALY CENTER OVER THE CENTRAL STATES. GIVEN THE PERSISTENCE OF THE NEGATIVE CENTER OVER THE CANADIAN MARITIMES... TELECONNECTIONS SUGGEST A PREFERENCE FOR THE RIDGE TO SET UP OVER THE EAST-CENTRAL LOWER 48 STATES... THOUGH WITH POSSIBLE RETROGRESSION OF THIS TROUGH WE WOULD EXPECT THE RIDGE TO CONSOLIDATE OVER THE CENTRAL STATES. THE WEEK 2 OPERATIONAL 6Z GFS SOLUTION ANTICIPATES THE RIDGE OVER THE WEST-CENTRAL STATES. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...30 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 20 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS BELOW AVERAGE... 2 ON A SCALE OF 1 TO 5... DUE TO THE UNCERTAINTY REGARDING THE UNUSUALLY LONG WAVELENGTH OVER THE CONUS NOTED EARLIER. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE ANALOG... NEURAL NET... AND KLEIN SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE GUIDANCE... THE CPC AUTO TEMPERATURE FORECAST... AND THE CDC TEMPERATURE TOOL. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO PRECIPITATION FORECAST... AND THE CDC PRECIPITATION TOOL. CPC CALIBRATED PRECIPITATION FROM THE GFS ENSEMBLES WAS ALSO CONSULTED... AS WELL AS THE DAILY PRECIPITATION FORECASTS AND MEAN STORM TRACKS FROM THE 12Z GFS RUN. 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 MAY 17. 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: 19800419 - 19520425 - 19940513 - 19760510 - 19580415 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: 19800419 - 19520424 - 19760510 - 19580415 - 19820429 6 to 10 day Outlook Table OUTLOOK FOR MAY 09 - 13, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B B OREGON N B NRN CALIF A B SRN CALIF A N IDAHO A N NEVADA A B W MONTANA A N E MONTANA A A WYOMING A N UTAH A B ARIZONA A N COLORADO A B NEW MEXICO A N N DAKOTA A N S DAKOTA A N NEBRASKA A N KANSAS A N OKLAHOMA A A N TEXAS N N S TEXAS N B W TEXAS A N MINNESOTA A N IOWA A A MISSOURI A A ARKANSAS A N LOUISIANA N B WISCONSIN A A ILLINOIS A A MISSISSIPPI A B MICHIGAN A A INDIANA A A OHIO A A KENTUCKY A N TENNESSEE A B ALABAMA A B NEW YORK A N VERMONT A N NEW HAMP A B MAINE A B MASS A B CONN A B RHODE IS A B PENN A N NEW JERSEY A N W VIRGINIA A N MARYLAND A N DELAWARE A N VIRGINIA A N N CAROLINA A N S CAROLINA A N GEORGIA A B FL PNHDL N B FL PENIN N B AK N SLOPE B B AK ALEUTIAN B B AK WESTERN B N AK INT BSN N B AK S INT N N AK SO COAST N N AK PNHDL B N 8 to 14 day Outlook Table OUTLOOK FOR MAY 11 - 17, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N N NRN CALIF N N SRN CALIF A B IDAHO A N NEVADA N B W MONTANA A N E MONTANA A A WYOMING A B UTAH A B ARIZONA A B COLORADO A B NEW MEXICO A B N DAKOTA A A S DAKOTA A N NEBRASKA A B KANSAS A B OKLAHOMA A B N TEXAS A B S TEXAS A N W TEXAS A B MINNESOTA A A IOWA A N MISSOURI A B ARKANSAS A B LOUISIANA A N WISCONSIN A A ILLINOIS A N MISSISSIPPI A B MICHIGAN A A INDIANA A N OHIO A N KENTUCKY A N TENNESSEE A B ALABAMA A B NEW YORK N B VERMONT B B NEW HAMP B B MAINE B B MASS B B CONN B B RHODE IS B B PENN A B NEW JERSEY N B W VIRGINIA A N MARYLAND A B DELAWARE A B VIRGINIA A B N CAROLINA A B S CAROLINA A B GEORGIA A B FL PNHDL A B FL PENIN N B AK N SLOPE B A AK ALEUTIAN N B AK WESTERN N B AK INT BSN A N AK S INT N B AK SO COAST N B 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. $$