PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EST FRI DEC 14 2007 6-10 DAY OUTLOOK VALID FOR DEC 20 - 24 2007 TODAY'S MODELS ARE IN GOOD AGREEMENT ON THE FORECASTED 6-10 DAY PERIOD 500 HPA FLOW PATTERN. THERE IS GENERAL AGREEMENT AMONG MODEL SOLUTIONS ON A FORECASTED DEEP TROUGH OVER ALASKA EXTENDING INTO WESTERN CANADA AND THE U.S. WEST., A RIDGE NORTH OF THE HAWAIIAN ISLANDS AND A RIDGE OVER EASTERN CANADA AND THE NORTHEAST CONUS. THE HIGH RESOLUTION 0Z AND 6Z MODELS LOCATE THE MEAN TROUGH AXIS OVER THE U.S. SOUTHWEST AND CENTRAL PLAINS RESPECTIVELY, WHILST YESTERDAY'S 12Z AND THE 0Z ECMWF HIGH RESOLUTION MODEL BRING A CUTOFF LOW THROUGH THE U.S. SOUTHEAST EARLY IN THE PERIOD LOWERING MEAN MID-LEVEL HEIGHTS OVER THE SOUTHEAST SUBSTANTIALLY. THE GFS BASED AND CANADIAN ENSEMBLE MEANS INDICATE NEARLY ZONAL MEAN FLOW, WHILST THE 12Z ECMWF ENSEMBLE MEAN HAS MORE AMPLIFIED WESTERN TROUGH AND EASTERN RIDGE OVER THE CONUS. ANALOGS OF THE VARIOUS MODEL HEIGHT FIELDS AND TELECONNECTIONS ON THE NEGATIVE ANOMALY CENTERED OVER ALASKA MORE CLOSELY RESEMBLE THE 12Z ECMWF ENSEMBLE MEAN PATTERN. COOLER TEMPERATURES OVER THE EASTERN SEABOARD BEFORE THE PERIOD SHOULD GIVE WAY TO ABOVE NORMAL TEMPERATURES DURING THE PERIOD. MOST OF THE COUNTRY EAST OF THE WESTERN TROUGH AXIS SHOULD HAVE ABOVE NORMAL TEMPERATURES. NEAR TO BELOW NORMAL TEMPERATURES ARE EXPECTED FOR THE WESTERN THIRD OF CONUS UNDER BELOW NORMAL HEIGHTS OR NORTHERLY FLOW. THE U.S. WEST SHOULD CONTINUE TO RECEIVE ABOVE NORMAL PRECIPITATION ALONG AN ACTIVE STORM TRACK FROM THE PACIFIC NORTHWEST SOUTHEASTWARD INTO NORTHERN ARIZONA. THE NORTHERN PLAINS AND GREAT LAKES ARE EXPECTED TO RECEIVE BELOW MEDIAN PRECIPITATION AMOUNTS, WHILST FROM EAST TEXAS INTO THE LOWER MISSISSIPPI AND OHIO VALLEYS EXTENDING INTO THE MID-ATLANTIC STATES ABOVE MEDIAN PRECIPITATION IS FORECAST UNDER NEAR TO BELOW NORMAL HEIGHTS AND SOUTHWESTERLY FLOW. UNDER THE DEEP TROUGH FORECAST OVER ALASKA TEMPERATURES WELL BELOW NORMAL AND BELOW MEDIAN PRECIPITATION AMOUNTS ARE EXPECTED FOR MOST OF THE STATE. ON THE EASTERN SIDE OF THE TROUGH THE ALASKAN PANHANDLE SHOULD RECEIVE ABOVE MEDIAN PRECIPITATION. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...10 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...15 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...5 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 45 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 ABOUT AVERAGE... 3 ON A SCALE OF 1 TO 5 DUE TO GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS WITH SOME DISAGREEMENT BETWEEN THE HIGH RESOLUTION GFS AND ECMWF BASED SOLUTIONS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... THE CDC REFORECAST... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... KLEIN AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODELS... AND THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE GUIDANCE. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE CPC AUTO FORECAST... THE CDC REFORECAST... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODELS... AND CPC CALIBRATED PRECIPITATION FROM THE HIGH RESOLUTION GFS MODELS. 8-14 DAY OUTLOOK FOR DEC 22 - 28 2007: THE LAST FOUR GFS ENSEMBLES AND THE CANADIAN ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT FOR THE 8-14 DAY PERIOD FORECASTING SLOW PROGRESSION OF THE 500 HPA FLOW PATTERN WITH THE MEAN TROUGH AXIS MOVING INTO THE ROCKIES. THE OFFICIAL BLEND HAS NEAR TO BELOW NORMAL HEIGHTS OVER MOST OF THE CONUS WITH THE U.S. SOUTHEAST TRANSITIONING FROM NEAR TO BELOW NORMAL HEIGHTS BETWEEN THE 6-10 AND 8-14 DAY PERIODS. THE MEAN TEMPERATURE AND PRECIPITATION PATTERNS REMAIN SOMEWHAT SIMILAR FOR THE TWO FORECAST PERIODS WITH BELOW NORMAL TEMPERATURES IN THE WEST AND ABOVE NORMAL TEMPERATURES FORECAST FOR THE EASTERN HALF OF THE CONUS. SOUTHERN CALIFORNIA SHOULD BECOME DRIER LATER IN THE PERIOD AS THE PACIFIC RIDGE EXTENDS INTO THE COAST. THE DEEP TROUGH OVER ALASKA CONTINUES INTO WEEK 2 ALONG WITH NEAR TO BELOW NORMAL TEMPERATURES AND BELOW MEDIAN PRECIPITATION FOR MOST OF THE STATE EXCEPT FOR ABOVE MEDIAN PRECIPITATION OVER THE PANHANDLE. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 2 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 11...3 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 11...20 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...30 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...10 PERCENT OF YESTERDAY'S 12Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...10 PERCENT OF YESTERDAY'S 18Z GFS ENSEMBLE MEAN CENTERED ON DAY 10...AND 25 PERCENT OF TODAY'S CANADIAN ENSEMBLE 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 AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS AND GOOD CONTINUITY. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO FORECAST... THE CDC REFORECAST... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... KLEIN AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODELS... AND THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM TEMPERATURE GUIDANCE. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE CPC AUTO FORECAST... THE CDC REFORECAST... ANALOGS OF THE OFFICIAL BLEND AND VARIOUS MODELS... NEURAL NET SPECIFICATIONS FROM THE OFFICIAL BLEND AND VARIOUS MODELS... AND CPC CALIBRATED PRECIPITATION FROM THE HIGH RESOLUTION GFS MODELS. FORECASTER: D. COLLINS 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 DECEMBER 20. 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: 19911201 - 19881228 - 19981222 - 19711227 - 19611213 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: 19911201 - 19981221 - 19711227 - 19901223 - 19611213 6 to 10 day Outlook Table OUTLOOK FOR DEC 20 - 24, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N A OREGON N A NRN CALIF B A SRN CALIF B A IDAHO N A NEVADA B A W MONTANA N B E MONTANA A B WYOMING N N UTAH B A ARIZONA N N COLORADO N A NEW MEXICO N N N DAKOTA A B S DAKOTA A B NEBRASKA A B KANSAS A N OKLAHOMA A N N TEXAS A N S TEXAS A N W TEXAS A N MINNESOTA A B IOWA A N MISSOURI A A ARKANSAS A A LOUISIANA A N WISCONSIN A B ILLINOIS A N MISSISSIPPI A A MICHIGAN A N INDIANA A A OHIO A A KENTUCKY A A TENNESSEE A A ALABAMA A N NEW YORK A N VERMONT A N NEW HAMP N N MAINE N N MASS N A CONN A A RHODE IS N A PENN A A NEW JERSEY A A W VIRGINIA A A MARYLAND A A DELAWARE A A VIRGINIA A A N CAROLINA A A S CAROLINA A A GEORGIA A N FL PNHDL A N FL PENIN A B AK N SLOPE N B AK ALEUTIAN B B AK WESTERN B B AK INT BSN B B AK S INT B B AK SO COAST B B AK PNHDL N A 8 to 14 day Outlook Table OUTLOOK FOR DEC 22 - 28, 2007 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N A OREGON N A NRN CALIF B A SRN CALIF B N IDAHO B A NEVADA B N W MONTANA A N E MONTANA A B WYOMING N B UTAH B N ARIZONA N N COLORADO N B NEW MEXICO N N N DAKOTA A B S DAKOTA A B NEBRASKA A B KANSAS A N OKLAHOMA A A N TEXAS A A S TEXAS N A W TEXAS N A MINNESOTA A B IOWA A B MISSOURI A A ARKANSAS A A LOUISIANA A A WISCONSIN A B ILLINOIS A N MISSISSIPPI A N MICHIGAN A N INDIANA A A OHIO A A KENTUCKY A A TENNESSEE A A ALABAMA A N NEW YORK A A VERMONT A N NEW HAMP A N MAINE A N MASS A A CONN A A RHODE IS A A PENN A A NEW JERSEY A A W VIRGINIA A A MARYLAND A A DELAWARE A A VIRGINIA A A N CAROLINA A A S CAROLINA A N GEORGIA A N FL PNHDL A B FL PENIN A B AK N SLOPE N B AK ALEUTIAN B N AK WESTERN B B AK INT BSN B B AK S INT B N AK SO COAST B 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. $$