PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT TUE APR 15 2008 6-10 DAY OUTLOOK VALID FOR APR 21 - 25 2008 TODAYS ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE MEAN 500-HPA HEIGHT PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD. THE OUTSTANDING FEATURE THIS PERIOD IS THE HIGHLY AMPLIFIED UPPER LEVEL TROUGH THAT DOMINATES THE WEST AT THE START OF THE FORECAST PERIOD. THIS SYSTEM SHOULD SLOWLY TRACK EASTWARD, BRINGING PLENTIFUL PRECIPITATION TO THE ROCKIES, CENTRAL STATES, AND THE SOUTH. THE OTHER INTERESTING FEATURE IS THE CLOSED UPPER LEVEL LOW FORECAST TO AFFECT THE EAST COAST AROUND APRIL 21-23. MODELS DIFFER ON THE LOCATION OF THE SURFACE LOW, BUT THE BEST CHANCE FOR HEAVY RAIN APPEARS TO BE THE MID-ATLANTIC REGION. IN THE WEST, FORECAST TOOLS ARE VERY MUCH IN AGREEMENT ON THE COLD AIR CENTERED NEAR MONTANA AND EXTENDING ACROSS THE WESTERN HALF OF THE CONUS. SOUTHERLY FLOW AHEAD OF THE TROUGH SHOULD MAINTAIN ABOVE NORMAL TEMPERATURES FROM THE MIDWEST TO THE GULF COAST, WHILE THE UPPER LOW AND LOW LEVEL EASTERLY FLOW SHOULD KEEP TEMPERATURES DOWN NEAR THE EAST COAST. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...20 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 60 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: 12Z ECMWF ENSEMBLE MEAN BUT NO STRONG PREFERENCES FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO FAIR AGREEMENT BETWEEN THE ECMWF, CANADIAN AND GFS ENSEMBLE MEAN SOLUTIONS, AND SOME DISAGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION TOOLS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE ANALOG SPECIFICATIONS OF THE OFFICIAL BLEND, NAEFS, AND THE GFS ENSEMBLE 850-MB TEMPERATURE ANOMALY. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS OF THE OFFICIAL BLEND AND PRECIPITATION TOTALS FROM VARIOUS MODELS, INCLUDING THE 0Z ECMWF. 8-14 DAY OUTLOOK FOR APR 23 - 29 2008: THE FORECAST 8-14 DAY UPPER LEVEL FLOW PATTERN HAS THE MEAN TROUGH FARTHER WEST AND LOCATED CLOSER TO THE MIDDLE OF THE CONUS, WITH WEAK RIDGING OFF THE NORTHEAST COAST AND OFF THE WEST COAST. WITH THE EAST COAST UPPER LOW MOSTLY OUT OF THE PICTURE THIS PERIOD, ABOVE NORMAL TEMPERATURES SHOULD MAKE THEIR WAY TO THE COAST. TEMPERATURES ARE FORECAST TO REMAIN COLD OVER THE WEST, BUT EXTENT AND THE INTENSITY OF THE COLD SHOULD DIMINISH. HEAVY RAINS MAY REMAIN A THREAT, HOWEVER, IN THE MIDWEST AND MISSISSIPPI VALLEY. THE 0Z GFS ENSEMBLE SHOWS A HIGH PROBABILITY OF AMOUNTS EXCEEDING 2 INCHES IN THE LOWER MISSISSIPPI VALLEY. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 50 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11...AND 50 PERCENT OF TODAY'S AUTO BLEND CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO FAIR AGREEMENT BETWEEN THE CANADIAN AND GFS ENSEMBLE MEAN UPPER-LEVEL HEIGHT PATTERNS, AND SOME DISAGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION TOOLS. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST, ANALOG SPECIFICATIONS OF THE OFFICIAL BLEND, AND BIAS-ADJUSTED GFS ENSEMBLE SURFACE MEAN TEMPERATURES. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS OF THE OFFICIAL BLEND AND OUTPUT FROM THE GFS ENSEMBLE AND OPERATIONAL MODELS. FORECASTER: D. LE COMTE 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 APRIL 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: 19520327 - 19620411 - 19960429 - 19890406 - 19590413 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: 19880327 - 19520326 - 19730424 - 19810406 - 19550413 6 to 10 day Outlook Table OUTLOOK FOR APR 21 - 25, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B N NRN CALIF B N SRN CALIF B B IDAHO B A NEVADA B N W MONTANA B A E MONTANA B A WYOMING B A UTAH B N ARIZONA B B COLORADO B N NEW MEXICO B N N DAKOTA B A S DAKOTA B A NEBRASKA B A KANSAS N A OKLAHOMA N A N TEXAS A A S TEXAS A N W TEXAS N N MINNESOTA N A IOWA N 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 A KENTUCKY A A TENNESSEE A A ALABAMA A A NEW YORK A N VERMONT A N NEW HAMP A N MAINE A N MASS A N CONN N N RHODE IS N N PENN A N NEW JERSEY N A W VIRGINIA A N MARYLAND N A DELAWARE N A VIRGINIA N A N CAROLINA N A S CAROLINA N A GEORGIA N N FL PNHDL N N FL PENIN B N AK N SLOPE A A AK ALEUTIAN A A AK WESTERN A A AK INT BSN A B AK S INT A A AK SO COAST A A AK PNHDL B B 8 to 14 day Outlook Table OUTLOOK FOR APR 23 - 29, 2008 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B B NRN CALIF N B SRN CALIF N B IDAHO B N NEVADA B B W MONTANA B N E MONTANA B A WYOMING B N UTAH B B ARIZONA N B COLORADO B B NEW MEXICO N B N DAKOTA B A S DAKOTA B A NEBRASKA B A KANSAS N A OKLAHOMA N A N TEXAS N A S TEXAS N N W TEXAS N N MINNESOTA B A IOWA N A MISSOURI N A ARKANSAS A A LOUISIANA A A WISCONSIN N A ILLINOIS A A MISSISSIPPI A A MICHIGAN A A INDIANA A A OHIO A A KENTUCKY A A TENNESSEE A A ALABAMA A A NEW YORK A N VERMONT A B NEW HAMP A B MAINE A B MASS A B CONN A B RHODE IS A B PENN A N NEW JERSEY A B W VIRGINIA A N MARYLAND A N DELAWARE A N VIRGINIA A N N CAROLINA A N S CAROLINA A N GEORGIA A N FL PNHDL N N FL PENIN N N AK N SLOPE A A AK ALEUTIAN N A AK WESTERN A A AK INT BSN A A AK S INT A A AK SO COAST A A 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. $$