PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT WED APR 26 2006 6-10 DAY OUTLOOK VALID FOR MAY 02 - 06 2006 TODAY'S GFS AND ECMWF ENSEMBLE MEAN FORECASTS ARE AGAIN IN RATHER GOOD AGREEMENT AND CONTINUE A SPLIT-FLOW 500-HPA PATTERN OVER NORTH AMERICA FOR THE 5-10 DAY PERIOD. THERE IS ALSO GOOD AGREMENT AMONG THE MODELS THAT THE POSITIVE ANOMALY CENTER ASSOCIATED WITH THE WESTERN RIDGE WILL RETROGRADE FURTHER... AT LEAST AS FAR AS THE VICINITY OF VANCOUVER ISLAND. AS A GROUP... THE ECMWF MODEL SOLTUIONS TAKE IT FURTHER WEST THAN THE GFS MODEL SOLUTIONS DO... AND THE HIGH RESOLUTION OPERATIONAL RUNS OF BOTH MODELS RETROGRADE IT MORE THAN THE CORRESPONDING ENSEMBLE MEANS. MOST MODELS SHOW THE TROUGH PREDICTED NEAR THE SOUTH ATLANTIC COAST SLIGHTLY STRONGER AND A LITTLE BROADER THAN THEY DID YESTERDAY... WITH RELATIVELY MINOR DIFFERENCES IN THE PHASE. THE CANADIAN ENSEMBLE MEAN AND DAVA SOLUTIONS ARE IN SOMEWHAT BETTER AGREEMENT TODAY WITH THE GFS AND ECMWF MODELS THAN THEY WERE EARLIER THIS WEEK. THE MODELS CONTINUE TO SHOW FAIRLY GOOD CONTINUITY WITH RESPECT TO THEIR RECENT SOLUTIONS. IN THE MEAN... AS DEPICTED BY THE OFFICIAL 500-HPA PROG... HEIGHTS WILL BE ABOVE NORMAL ACROSS THE NORTHWESTERN TWO-THIRDS OF THE CONUS AND SOUTHWESTERN CANADA... WITH A MODERATELY STRONG TROUGH JUST OFF THE SOUTH ATLANTIC COAST AND A WEAK TROUGH OFF BAJA CALIFORNIA. HEIGHTS ARE EXPECTED TO BE NEAR OR SLIGHTLY ABOVE NORMAL OVER EASTERN CANADA AND THE ADJACENT ATLANTIC... BUT A STRONG NEGATIVELY-TILTED TROUGH IS INDICATED FOR THE VICINITY OF ICELAND AND THE BRITISH ISLES. HEIGHTS ARE PREDICTED TO BE SLIGHTLY BELOW NORMAL ACROSS MOST OF ALASKA AND NORTHERN CANADA... BUT ABOVE NORMAL ACROSS MOST OF THE ASIAN SIDE OF THE ARCTIC BASIN WITH A VERY STRONG RIDGE AND POSITIVE HEIGHT ANOMALY CENTERED OVER THE BARENTS SEA. A SOMEWHAT WEAKER RIDGE AND POSITIVE HEIGHT ANOMALY CENTER IS INDICATED FOR THE WESTERN BERING SEA. TEMPERATURES ACROSS MOST OF THE WESTERN HALF OF THE CONUS ARE FORECAST TO BE NEAR OR ABOVE NORMAL UNDER THE INFLUENCE OF THE ZONALLY-ORIENTED RIDGE AND ASSOCIATED AREA OF ABOVE NORMAL HEIGHTS. BELOW NORMAL TEMPERATURES ARE EXPECTED OVER MUCH OF THE SOUTHEASTERN STATES AND PARTS OF ALASKA... ALTHOUGH THEY APPEAR TO BE MODERATING IN THE LATTER AREA. PRECIPITATION ACROSS THE NORTHERN TIER OF STATES AND MUCH OF THE WESTERN CONUS IS FORECAST TO BE BELOW NORMAL DUE TO SUBSIDENCE ASSOCIATED WITH THE EXTENSIVE AND STRONG RIDGE... WHILE ABOVE NORMAL PRECIPITATION IS ANTICIPATED OVER PARTS OF THE SOUTHEAST AND THE MIDDLE ATLANTIC COAST... AS WELL AS OVER SOUTHEASTERN ALASKA WHERE ONSHORE FLOW IS RELATIVELY STRONG. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...5 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...20 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...5 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 25 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: 12Z ECMWF ENSEMBLE MEAN. FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE TODAY... 4 ON A SCALE OF 1 TO 5... DUE TO GOOD MODEL AGREEMENT AND CONSISTENCY WITH PREVIOUS MODEL RUNS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... ANALOG... AND NEURAL NETWORK SPECIFICATIONS FROM THE OFFICIAL BLEND... THE CPC AUTO TEMPERATURE FORECAST... THE CDC CALIBRATED TEMPERATURE PROBABILITIES... AND THE CALIBRATED 2M TEMPERATURES FROM THE 0Z GFS ENSEMBLE MEAN. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND THE INDIVIDUAL FORECAST MODELS... THE CPC AUTO PRECIPITATION FORECAST... EMC AND CPC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES... AND CDC CALIBRATED PRECIPITATION PROBABILITIES FROM THE 0Z GFS ENSEMBLE MEAN. 8-14 DAY OUTLOOK FOR MAY 04 - 10 2006: DURING WEEK 2 THE VARIOUS GFS ENSEMBLE MEAN AND OPERATIONAL RUNS CONTINUE TO BE IN QUITE GOOD AGREEMENT FOR THIS RANGE. OVERALL... THEY PREDICT ADDITIONAL DEEPENING OF THE 500-HPA TROUGH OVER EASTERN NORTH AMERICA... WHILE THE WESTERN RIDGE IS EXPECTED TO WEAKEN AND MOVE EASTWARD SOMEWHAT FROM ITS INDICATED POSITION DURING THE 6-10 DAY PERIOD. THIS FORECAST PROGRESSION SEEMS TO COME ABOUT DUE TO A FORECAST PROGRESSION OF THE WAVE TRAIN OVER THE PACIFIC. THE RIDGE PREDICTED SOUTHEAST OF THE CANADIAN MARITIMES DURING THE 6-10 DAY PERIOD IS EXPECTTED TO WEAKEN SOMEWHAT... WHILE THE ASSOCIATED POSITIVE ANOMALY CENTER IS FORECAST NEAR THE DAVIS STRAIT AREA. A STRONG RIDGE IS EXPECTED TO REMAIN OVER THE BARENTS SEA... WHILE THE RIDGE OVER THE BERING SEA IS PREDICTED TO FLATTEN SOMEWHAT WITH THE ASSOCIATED POSITIVE ANOMALY CENTER MOVING SOUTH OF THE ALEUTIANS. AS A RESULT OF THESE MOSTLY GRADUAL CHANGES IN THE HEIGHT PATTERN FROM THAT INDICATED FOR THE 6-10 DAY FORECAST PERIOD... THE TEMPERATURES AND PRECIPITATION PATTERNS ARE ALSO EXPECTED TO BE SIMILAR... CONTINUED ABNORMALLY WARM AND DRY OVER THE WESTERN CONUS... WITH SOME EXPANSION OF THE AREA OF BELOW NORMAL TEMPERATURES OVER THE EASTERN CONUS DUE TO EXPECTED DEEPENING OF THE TROUGH OVER THE GREAT LAKES REGION. MUCH OF THE CONUS AND ALASKA ARE EXPECTED TO BE DRY DUE TO LACK OF MOISTURE WITH THE FLOW ANOMALIES EITHER STRONGLY ANTICYCLONIC OR FROM INTERIOR CONTINENTAL SOURCES IN MOST AREAS. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...5 PERCENT OF YESTERDAY'S OPERATIONAL 12Z GFS CENTERED ON DAY 10...5 PERCENT OF YESTERDAY'S OPERATIONAL 18Z GFS CENTERED ON DAY 10...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...5 PERCENT OF YESTERDAY'S 12Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...5 PERCENT OF YESTERDAY'S 18Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...AND 20 PERCENT OF TODAY'S GFS SUPERENSEMBLE 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 AND CONSISTENCY WITH PREVIOUSLY INDICATED FORECAST PATTERNS AND TRENDS. THERE IS A SLIGHT DECREASE IN CONFIDENCE OF THE PREDICTED TEMPERATURE AND PRECIPITATION ANOMALY PROBABILITIES DUE TO PREDICTED WEAKENING OF THE CIRCULATION ANOMALIES. 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... KLEIN PROBABILITIES FROM THE GFS ENSEMBLE MEMBERS... UNCALIBRATED AND CALIBRATED 2 METER TEMPERATURES FROM THE 0Z GFS ENSEMBLE MEMBERS... AND THE CDC CALIBRATED TEMPERATURE PROBABILITIES. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND... ANALOG SPECIFICATIONS FROM THE GFS ENSEMBLE MEANS... CPC AND EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLE MEMBERS... AND CDC CALIBRATED PRECIPITATION PROBABILITIES. FORECASTER: WAGNER 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 18. AN UPDATED MONTHLY FORECAST FOR MAY WILL BE ISSUED ON APRIL 30. 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: 19800424 - 19800429 - 19730503 - 19710510 - 19870406 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: 19800425 - 19800430 - 19750508 - 19880408 - 19840414 6 to 10 day Outlook Table OUTLOOK FOR MAY 02 - 06, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A B OREGON A B NRN CALIF A B SRN CALIF A B IDAHO A B NEVADA A B W MONTANA A B E MONTANA A B WYOMING A B UTAH A B ARIZONA A N COLORADO A N NEW MEXICO A A N DAKOTA A B S DAKOTA A B NEBRASKA N B KANSAS N B OKLAHOMA N B N TEXAS N B S TEXAS N N W TEXAS N N MINNESOTA N B IOWA N B MISSOURI N B ARKANSAS B B LOUISIANA B N WISCONSIN N B ILLINOIS N B MISSISSIPPI B N MICHIGAN N B INDIANA N B OHIO N N KENTUCKY B B TENNESSEE B N ALABAMA B N NEW YORK N N VERMONT N A NEW HAMP N A MAINE A A MASS N A CONN B A RHODE IS B A PENN N N NEW JERSEY B N W VIRGINIA B N MARYLAND B N DELAWARE B N VIRGINIA B N N CAROLINA B N S CAROLINA B N GEORGIA B N FL PNHDL B N FL PENIN B B AK N SLOPE B N AK ALEUTIAN B B AK WESTERN B B AK INT BSN B N AK S INT N A AK SO COAST N A AK PNHDL N A 8 to 14 day Outlook Table OUTLOOK FOR MAY 04 - 10, 2006 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A B OREGON A B NRN CALIF A B SRN CALIF A B IDAHO A B NEVADA A B W MONTANA A B E MONTANA A B WYOMING A B UTAH A B ARIZONA A B COLORADO A B NEW MEXICO A B N DAKOTA A B S DAKOTA A B NEBRASKA A B KANSAS A B OKLAHOMA N B N TEXAS N B S TEXAS N B W TEXAS A B MINNESOTA N B IOWA N B MISSOURI N B ARKANSAS B B LOUISIANA B B WISCONSIN B B ILLINOIS B B MISSISSIPPI B B MICHIGAN B N INDIANA B B OHIO B N KENTUCKY B B TENNESSEE B B ALABAMA B B NEW YORK B N VERMONT B N NEW HAMP B N MAINE B A MASS B N CONN B N RHODE IS B N PENN B N NEW JERSEY B N W VIRGINIA B N MARYLAND B N DELAWARE B N VIRGINIA B N N CAROLINA B N S CAROLINA B N GEORGIA B N FL PNHDL B N FL PENIN N B AK N SLOPE B N AK ALEUTIAN N B AK WESTERN N B AK INT BSN B N AK S INT N N AK SO COAST N N 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. $$