PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EST FRI MAR 19 2004 6 TO 10 DAY OUTLOOK FOR MAR 25 - MAR 29 2004 . . . . . . . THROUGH DAY 5 THE MODELS HAVE MOSTLY GOOD AGREEMENT ON THE LONG WAVES AND THERE ARE ONLY SMALL DIFFERENCES IN THE SHORT WAVES EXCEPT IN THE VICINITY OF ALASKA. THE MAIN DIFFERENCE IS THAT THE 0Z AND 06Z GFS RUNS HAVE THE POLAR VORTEX IN CANADA FARTHER SOUTH AND EAST THAN EARLIER RUNS... SUGGESTING THAT IT WILL BE HARD TO GET WARM AIR INTO THE NORTHERN BORDER AND THE NORTHEASTERN STATES AT THE SURFACE EVEN THOUGH A VERY STRONG RIDGE IS STILL PREDICTED ACROSS THE ENTIRE CONUS. THE MODELS ARE IN STILL IN GENERALLY GOOD AGREEMENT FOR THE 6-10 DAY PERIOD OVER THE CONUS BUT UNCERTAINTIES ARE SHOWING IN BOTH THE LCOATION AND INTENSITY OF THE ALASKA BLOCKING RIDGE. THE 6Z GFS RUN PLACES IT OVER EASTERN ALASKA AND JOINS THE RIDGE OVER THE CONUS WITH IT... GIVING STRONG NORTHWESTERLY FLOW TO ITS EAST WHICH WOULD KEEP THE NORTHEASTERN U.S. COLD EXCEPT FOR A FEW INDIVIDUAL WARM DAYS. MOST MODELS STILL PLACE A STRONG POSITIVE ANOMALY CENTER OVER THE NORTHEASTERN U.S. OR SOUTH OF NEWFOUNDLAND. ANOTHER DIFFERENCE IN MODELS IS THAT THE GFS RUNS GENERALLY SEAL OFF A CUT OFF LOW WEST OF THE PACIFIC NORTHWEST COAST... BUT THE ECMWF INDIVIDUAL HIGH RESOLUTION RUN AND THE ECMWF ENSEMBLE BOTH CONNECT THE NEGATIVE ANOMALIES OVER CANADA AND THE NORTHEASTERN PACIFIC. ALTHOUGH 500-HPA HEIGHTS ARE GRNERALLY BELOW NORMAL OVER THE ARCTIC NEAR THE BEGINNING OF THE PERIOD... THE RIDGES OVER NORTHWESTERN RUSSIA AND THE BERING SEA ARE BEGINNING TO PUSH NORTHWARD INTO THE ARCTIC AND JOIN ACROSS THE POLE... FORESHADOWING A RETURN TO A NEGATIVE AO. TELECONNECTIONS FROM THE ALEUTIAN AND EASTERN U.S. POSITIVE ANOMALY CENTERS ARE REASONABLY COMPATIBLE WITH EACH OTHER AND WITH THE OTHER LARGE-SCALE HEIGHT ANOMALIES PREDICTED NEAR NORTH AMERICA. MODEL OF THE DAY: EUROPEAN ENSEMBLE MEAN DUE TO SUPERIOR ANOMALY CORRELATION SCORES DURING THE LAST 60 DAYS... FOLLOWED CLOSELY BY THE GFS ENSEMBLE MEAN. THE OFFICIAL HEIGHT PROG FOR TODAY CONSISTS OF 25 PERCENT OF THE ECMWF ENSEMBLE MEAN CENTERED ON DAY 7... 15 PERCENT OF THE HIGH RESOLUTION ECMWF SOLUTION CENTERED ON DAY 7... 15 PERCENT EACH OF THE 12Z AND 6Z OPERATIONAL GFS RUNS CENTERED ON DAY 7 AND 8 RESPECTIVELY... 10 PERCENT OF THE 0Z GFS CENTERED ON DAY 8... AND 20 PERCENT OF THE GFS ENSEMBLE MEAN CENTERED ON DAY 8. FORECAST CONFIDENCE FOR THE 6 TO 10 DAY PERIOD REMAINS BARELY ABOVE AVERAGE TODAY... 4 ON A SCALE FROM 1 TO 5... DUE TO MOSTLY GOOD MODEL AGREEMENT OVER THE CONUS AND GOOD TELECONNECTIVITY OF THE OVERALL PATTERN. HOWEVER... THE FORECAST OVER ALASKA IS JUDGED TO BE OF RELATIVELY LOW CONFIDENCE... AND IT IS BELIEVED THAT THE KLEIN AND NEURAL NET FORECAST TOOLS FOR TEMPERATURE SPECIFIED FROM MIDDLE TROPOSPHERIC HEIGHTS DO NOT PROPERLY ACOUNT FOR LOW-LEVEL COLD AIR ASSOCIATED WITH BACK DOOR COLD FRONTS OVER THE NORTHEASTERN CONUS SUGGESTED BY MANY OF THE GFS DAILY SURFACE PROGS. THE 6 TO 10 DAY TEMPERATURE PROG IS BASED ON KLEIN AND NEURAL NET SPECIFICATIONS FROM THE BLEND... COMPOSITE ANALOGS FROM THE BLEND... THE BIAS CORRECTED 850-HPA TEMPERATURES FROM THE 0Z OPERATIONAL GFS... AND CDC CALIBRATED TEMPERATURES... ALL SUBJECTIVELY MODIFIED FOR THE REASONS DISCUSSED ABOVE. THE 6 TO 10 DAY PRECIPITATION PROG IS BASED ON THE BIAS CORRECTED AND CALIBRATED PRECIPITATION FROM THE 0Z GFS... ANALOGS AND NEURAL NETS FROM THE BLEND ... THE CDC CALIBRATED PRECIPITATION FORECAST AND THE CALIBRATED PRECIPITATION PROBABILITY PERCENTAGES FROM THE GFS ENSEMBLE. . . . . . . . 8 TO 14 DAY OUTLOOK FOR MAR 27 - APR 2 2004 THE MEAN PATTERNS PREDICTED BY THE AVAILABLE MODELS FOR THE 8-14 DAY PERIOD CONTINUE TO HAVE GREATER DIFFERENCES TODAY AND SOME SHOW SIGNIFICANT LOCALIZED CHANGES FROM THE PATTERNS PREDICTED FOR THE 6-10 DAY PERIOD. THE GFS HIGH RESOLUTION MODELS ESPECIALLY MOVE THE CORE OF THE COLD POLAR VORTEX OUT OVER THE NORTH ATLANTIC IN THE VICINITY OF SOUTHERN GREENLAND... WHILE LOWERING HEIGHTS SIGNIFICNATLY OVER THE NORTHWESTERN ATLANTIC EAST OF THE CANADIAN MARITIMES. THE ENESEMBLE MEAN TRENDS THIS WAY... BUT WITH WEAKER HEIGHT ANOMALIES. THE FORECAST OVER ALAKSA IS ALMOST A COMPLETE TOSS-UP... WITH SOME ENSEMBLE MEMBERS MAINTAINING THE BLOCK IN A WEAKENED FORM... SOME SPLITTING IT AND RETROGRADING PART OF IT TO NORTHEASTERN SIBERIA WHILE DROPPING THE REMNANTS OF THE ORIGINAL BLOCK SOUTHWARD OVER THE GULF OF ALASKA... AND A FEW... INCLUDING THE 0Z OPERATIONAL GFS... EVEN REPLACING IT WITH A WEAK TROUGH OVER ALASKA. THE ENSEMBLE SPAGHETTI DIAGRAMS ALSO GENERALLY MORE IN DISAGREEMENT TODAY... ESPECIALLY IN THE NORTH PACIFIC NEAR ALASKA... AS WELL AS AT LOWER LATITUDES OF THE WESTERN ATLANTIC WHERE SOME MEMBERS SHOW A TROUGH RATHER THAN A STRONG RIDGE. THE OFFICIAL 500-HPA HEIGHT PROG FOR TODAY CONSISTS OF 20 PERCENT OF THE 0Z OPERATIONAL GFS CENTERED ON DAY 11... 20 PERCENT OF THE 6Z OPERATIONAL GFS CENTERED DAY 11... 30 PERCENT OF THE GFS ENSEMBLE MEAN CENTERED ON DAY 11... 20 PERCENT OF THE ECMWF ENSEMBLE MEAN AND 10 PERCENT OF THE ECMWF HIGH RESOLUTION RUN... BOTH OF THE LATTER CENTERED ON DAY 7. FORECAST CONFIDENCE FOR THE 8 TO 14 DAY PERIOD REMAINS AVERAGE TODAY... 3 ON A SCALE FROM 1 TO 5... DUE TO REAONABLY GOOD MODEL AGREEMENT OVER THE CONUS... BUT THE ALASKA FORECAST IS ALMOST A COIN TOSS DUE TO MODEL DIFFERENCS AND THE TEMPERATURE FORECAST OVER THE NORTHEASTERN CONUS IS SOMEWHAT LESS CERTAIN DUE TO THE POSSIBLE INFLUENCE OF SHALLOW COLD AIR NOT INDICATED BY THE TEMPERATURE TOOLS. THE 8 TO 14 DAY TEMPERATURE PROG IS BASED ON KLEIN AND NEURAL NET SPECIFICATIONS FROM THE BLEND... ANALOGS FROM THE BLEND... THE BIAS CORRECTED 850-HPA TEMPERATURES FROM THE 0Z OPERATIONAL GFS AND THE CDC 8 TO 14 DAY CALIBRATED TEMPERATURE FORECAST. THE 8 TO 14 DAY PRECIPITATION PROG IS BASED ON THE CALIBRATED AND BIAS CORRECTED PRECIPITATION FROM THE 0Z GFS...ANALOGS AND NEURAL NETS FROM THE BLEND... THE CDC CALIBRATED PRECIPITATION FORECAST AND THE CALIBRATED PRECIPITATION PROBABILITY PERCENTAGES FROM THE GFS ENSEMBLE. FORECASTER: A. J. WAGNER . . . . . . . NOTES: 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. EFFECTIVE THURSDAY MAY 17 2001...THE CLIMATE PREDICTION CENTER HAS SWITCHED TO 1971-2000 BASE PERIOD MEANS FOR TEMPERATURE... PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN THE CLIMATE OUTLOOKS. THE 1971-2000 BASE PERIOD MEANS HAVE REPLACED THE 1961-1990 BASE PERIOD MEANS. THE NEXT MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED THURSDAY APRIL 15TH. 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: 19530306 - 19940314 - 19820310 - 19850402 - 19850301 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 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES: 19530306 - 19940314 - 19850402 - 19850227 - 19850301 6 to 10 day Outlook Table OUTLOOK FOR MAR 25 - 29, 2004 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N A NRN CALIF N A SRN CALIF N A IDAHO N N NEVADA A N W MONTANA N N E MONTANA N N WYOMING A B UTAH A N ARIZONA A B COLORADO A B NEW MEXICO A B N DAKOTA A N S DAKOTA A N NEBRASKA A B KANSAS A B OKLAHOMA A B N TEXAS A B S TEXAS A B W TEXAS A B MINNESOTA A A IOWA A A MISSOURI A N ARKANSAS A B LOUISIANA A 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 N N VERMONT N B NEW HAMP B B MAINE B N MASS B B CONN N B RHODE IS B B PENN A N NEW JERSEY N N W VIRGINIA A N MARYLAND N N DELAWARE N N VIRGINIA A B N CAROLINA A B S CAROLINA A B GEORGIA A B FL PNHDL N B FL PENIN N B AK N SLOPE N A AK ALEUTIAN N B AK WESTERN N B AK INT BSN B N AK S INT B B AK SO COAST B B AK PNHDL B B 8 to 14 day Outlook Table OUTLOOK FOR MAR 27 - APR 02, 2004 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N N NRN CALIF N A SRN CALIF N A IDAHO N N NEVADA N N W MONTANA N N E MONTANA N B WYOMING A B UTAH A A ARIZONA N A COLORADO A N NEW MEXICO A N N DAKOTA A N S DAKOTA A A NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A N S TEXAS A N W TEXAS A A MINNESOTA A A IOWA A A MISSOURI A A ARKANSAS A B LOUISIANA A B WISCONSIN A A ILLINOIS A A MISSISSIPPI A B MICHIGAN A A INDIANA A N OHIO A N KENTUCKY A B TENNESSEE A B ALABAMA A B NEW YORK A N VERMONT A N NEW HAMP N B MAINE N B MASS N B CONN N N RHODE IS N B PENN A N NEW JERSEY A N W VIRGINIA A B 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 A B AK N SLOPE N N AK ALEUTIAN N N AK WESTERN N N AK INT BSN B N AK S INT B B AK SO COAST B B AK PNHDL B N 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. $$