PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT TUE APR 10 2007 6-10 DAY OUTLOOK VALID FOR APR 16 - 20 2007 TODAYS NUMERICAL MODELS ARE NOT IN AS GOOD AGREEMENT THAN THEY WERE YESTERDAY ON THE LARGE SCALE FORECAST 500-HPA HEIGHT PATTERN OVER NORTH AMERICA... WITH THE GFS SOLUTIONS HAVING A STRONG TROUGH OVER THE EASTERN U.S. WHILE THE ECMWF ENSEMBLE MEAN HAS A BROAD TROUGH NEARLY COAST TO COAST AND THE OPERATIONAL RUNS OF THE ECMWF MODEL SHOW ONE TROUGH OFF THE EAST COAST AND ANOTHER TROUGH OVER THE WEST. THE DAVA MODEL AND THE CDC REFORECAST MODEL HAVE A RIDGE AND ABOVE NORMAL 500-HPA HEIGHTS EXTENDING INLAND FROM THE PACIFIC OVER THE PACIFIC NORTHWEST. MOST MODELS CONTINUE TO FORECAST BELOW NORMAL 500-HPA HEIGHTS OVER SOUTHERN CANADA AND MUCH OF THE CONUS EXCEPT FOR THE FAR WEST. MODELS ALSO AGREE ON AN EXTENSIVE AREA OF ABOVE NORMAL HEIGHTS ACROSS NORTHERN AND EASTERN CANADA JOINING WITH THE NORTHWESTERN ATLANTIC... AND A WELL-DEFINED POLAR LOW OVER THE ARCTIC OCEAN. THERE IS SOMEWHAT LESS AGREEMENT ON THE PREDICTED POSITION AND STRENGHT OF A RIDGE OFF THE PACIFIC COAST. ENHANCED WESTERLIES EXTEND ACROSS THE PACIFIC AT MID-LATITUDES... BUT THE FLOW IS SPLIT FROM THE CONUS ACROSS THE ATLANTIC THROUGH EUROPE AND INTO CENTRAL ASIA. TEMPERATURES ARE EXPECTED TO AVERAGE BELOW NORMAL OVER MUCH OF THE CONUS EAST OF THE CONTINENTAL DIVIDE IN RESPONSE TO GENERALLY BELOW NORMAL 500-HPA HEIGHTS. THE PATTERN FAVORS AN ACTIVE STORM TRACK ACROSS THE CONUS... BUT THE MEAN RIDGE PREDICTED OFF THE WEST COAST AND MEAN TROUGH FORECAST OVER THE EAST WOULD REDUCE THE AMOUNT OF SOUTHERLY FLOW AND MOISTURE CONTENT AVAILABLE TO MOST OF THE EXPECTED DISTURBANCES. FORECAST PATTERNS ARE SLOWLY CHANGING OVER ALASKA ALSO AND TOOLS SUGGEST THAT NEAR AND ABOVE MEDIAN PRECIPITATION COULD OCCUR ALONG THE SOUTH COAST AND PANHANDLE AREAS, WITH NEAR OR SLIGHTLY ABOVE NORMAL TEMPERATURES IN MOST AREAS. 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...5 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...5 PERCENT OF TODAY'S DAVA 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...15 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 10 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: NO STRONG PREFERENCE... SLIGHTLY GREATER WEIGHTS WERE ASSIGNED TO THE ENSEMBLE MEANS. FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS BELOW AVERAGE... 2 ON A SCALE OF 1 TO 5... DUE TO FAIR CONTINUITY FROM RECENT FORECASTS AND RATHER DIVERGENT SOLUTIONS OVER THE CONUS AMONG THE MODELS... OFFSET SOMEWHAT BY REASONABLE TELECONNECTIVITY TO THE REST OF THE PATTERN FROM THE STRONG POSITIVE ANOMALY CENTER PREDICTED OFF LABRADOR THAT MOST MODELS AGREED ON. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO TEMPERATURE FORECAST... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM GUIDANCE... AND THE CDC RE-FORECAST 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... CPC CALIBRATED PRECIPITATION FROM THE 0Z GFS ENSEMBLE AND OPERATIONAL MODEL... AND THE CDC RE-FORECAST PRECIPITATION TOOL. 8-14 DAY OUTLOOK FOR APR 18 - 24 2007: MODELS ARE ONLY IN FAIR AGREEMENT ON THE PREDICTED LARGE SCALE 500-HPA CIRCULATION PATTERN FOR THE 8 TO 14 DAY PERIOD... MOST OF THE ENSEMBLE MEAN MODELS AGREE THAT THE EASTERN TROUGH SHOULD PROGRESS TO A POSITION OFF THE EAST COAST... AND AT THE SAME TIME THEY MAINTAIN THE RIDGE OVER THE EASTERN PACIFIC WITH LITTLE CHANGE. THIS LEADS TO AN UNUSUALLY LONG WAVELENGTH FOR THIS TIME OF YEAR... AND THE INDIVIDUAL GFS MODELS SHOW A VARIETY OF SOLUTIONS AS TO THE LOCATION AND INTENSITY OF A NEW TROUGH SOEMWHERE IN THE WEST. MOST SHOW IT OVER WESTERN CANADA WITH AN EXTENSION SOUTHEASTWARD OVER THE NORTHWESTERN U.S. OR POSSIBLY AS FAR EAST AS THE NORTHERN GREAT PLAINS. IN SOME WAYS THE CANADIAN ENSEMBLE MEAN SHOWED A REASONABLE COMPROMISE WITH A VERY WEAK BROAD TROUGH THAT EXTENDS AT LEAST FROM THE ROCKIES TO THE EAST COAST... A PATTERN NOT TOO MUCH DIFFERENT FROM THAT PREDICTED FOR THE 6-10 DAY PERIOD. ALL MODELS SHOW A CONTINUATION OF THE AREA OF ABOVE NORMAL HEIGHTS PREDICTED TO EXTEND FROM THE ATLANTIC NORTHWESTWARD ACROSS NORTHEASTERN CANADA... AND TELECONNECTIONS FROM A POSITIVE 500-HPA CENTER EAST OF LABRADOR WERE IN REASONABLE AGREEMENT WITH THE REST OF THE FORECAST HEIGHT PATTERNS OVER NORTH AMERICA AND THE ATLANTIC. THE BLENDED HEIGHT PROG SHOWS A 500-HPA CIRCULATION PATTERN QUITE SIMILAR TO THAT OF THE 6 TO 10 DAY PERIOD... ALTHOUGH 500-HPA HEIGHTS ARE PREDICTED TO FALL OVER THE PACIFIC NORTHWEST AND RISE IN THE GREAT LAKES AND NORTHERN NEW ENGLAND AREAS. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...5 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...5 PERCENT OF TODAY'S DAVA 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...10 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 25 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS BELOW AVERAGE... 2 ON A SCALE OF 1 TO 5. ALTHOUGH THE GFS-BASED ENSEMBLE MEANS WERE IN GOOD AGREEMENT ON A TROUGH OFF THE EAST COAST... THE SIGN OF THE 500-HPA ANOMALY FIELD IS UNCERTAIN AND IN ANY CASE WEAK OVER MOST OF THE WESTERN HALF OF THE CONUS. THERE ARE ALSO CONSIDERABLE DIFFERENCES ELSEWHERE AMONG MANY OF THE GFS ENSEMBLE MEANS AND THE INDIVIDUAL GFS OPERATIONAL RUNS. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE ANALOG... NEURAL NET AND KLEIN SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO TEMPERATURE FORECAST... THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE GUIDANCE... AND THE CDC RE-FORECAST TEMPERATURE TOOL. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS FROM THE OFFICIAL BLENDED HEIGHT FIELD... THE CPC AUTO PRECIPITATION FORECAST... CPC CALIBRATED PRECIPITATION FROM THE 0Z GFS ENSEMBLE AND OPERATIONAL MODEL... AND THE CDC REFORECAST PRECIPITATION TOOL. FORECASTER: A. J. 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 APRIL 19. 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: 19970424 - 19660328 - 19880415 - 19550327 - 19530419 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: 19970423 - 19880414 - 19660328 - 19810322 - 19570329 6 to 10 day Outlook Table OUTLOOK FOR APR 16 - 20, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON A B NRN CALIF A B SRN CALIF A N IDAHO N N NEVADA A N W MONTANA N N E MONTANA N B WYOMING N A UTAH N N ARIZONA A N COLORADO N A NEW MEXICO N B N DAKOTA A B S DAKOTA N B NEBRASKA N A KANSAS B A OKLAHOMA B A N TEXAS B N S TEXAS B N W TEXAS B B MINNESOTA N B IOWA N B MISSOURI B N ARKANSAS B N LOUISIANA B N WISCONSIN N B ILLINOIS B B MISSISSIPPI B N MICHIGAN N B INDIANA B B OHIO B N KENTUCKY B N TENNESSEE B N ALABAMA B N NEW YORK B A VERMONT N A NEW HAMP N A MAINE N A MASS B A CONN B A RHODE IS B A PENN B A NEW JERSEY B A W VIRGINIA B A MARYLAND B A DELAWARE B A VIRGINIA B A N CAROLINA B N S CAROLINA B N GEORGIA B N FL PNHDL B N FL PENIN B N AK N SLOPE B B AK ALEUTIAN B N AK WESTERN B B AK INT BSN A N AK S INT A N AK SO COAST A A AK PNHDL N A 8 to 14 day Outlook Table OUTLOOK FOR APR 18 - 24, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A B OREGON A B NRN CALIF A B SRN CALIF A N IDAHO A B NEVADA A N W MONTANA A B E MONTANA A B WYOMING A B UTAH A N ARIZONA A N COLORADO A N NEW MEXICO A N N DAKOTA A B S DAKOTA A B NEBRASKA N N KANSAS N N OKLAHOMA B N N TEXAS B N S TEXAS B N W TEXAS N N MINNESOTA N B IOWA N B MISSOURI B N ARKANSAS B N LOUISIANA B N WISCONSIN N B ILLINOIS B B MISSISSIPPI B N MICHIGAN N B INDIANA B B OHIO B B KENTUCKY B N TENNESSEE B N ALABAMA B N NEW YORK N N VERMONT N N NEW HAMP N N MAINE A A MASS N N CONN N N RHODE IS N N PENN N N NEW JERSEY N N W VIRGINIA B N MARYLAND B N DELAWARE B N VIRGINIA B N N CAROLINA B A S CAROLINA B A GEORGIA B N FL PNHDL B A FL PENIN B A AK N SLOPE N B AK ALEUTIAN B N AK WESTERN B B AK INT BSN N B AK S INT A N AK SO COAST A 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. $$