PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EDT TUE JUN 08 2004 6 TO 10 DAY OUTLOOK FOR JUNE 14 - 18 2004 . . . . . . . AN INSPECTION OF MODEL RUNS FOR BOTH TODAY AND YESTERDAY INDICATES ONLY FAIR AGREEMENT BETWEEN VARIOUS SOLUTIONS OVER THE NORTH AMER- ICAN SECTOR DURING DAYS 6-10. THERE ARE ENOUGH DISCREPANCIES TO SIGNIFICANTLY INCREASE THE UNCERTAINTY OF THIS FORECAST...AND MANY OF THE MODELS ARE PREDICTING WEAK TO VERY WEAK HEIGHT ANOMALIES ACROSS THE CONUS. IN A VERY GENERAL SENSE...THE KEY FEATURES OF THE MEAN CIRCULATION FOR DAYS 6-10 INCLUDE ANOMALOUS RIDGING SOUTH OF THE ALEUTIANS... TROUGHS OVER THE WESTERN BERING SEA AND JUST OFF THE BRITISH COLUMBIA COAST... A TROUGH OVER THE U.S. MIDWEST... AND WEAK RIDGES OVER THE NORTHERN GREAT BASIN OR NORTHERN ROCKIES AND OVER THE NORTH ATLANTIC POKING WESTWARD INTO EASTERN CANADA. A FAIRLY STRONG TROUGH WAS INDICATED BY MOST MODELS JUST SOUTHEAST OF THE CANADIAN MARITIMES. MANY MODELS... THE ECMWF AND DAVA EXCEPTED... ARE INDICATING A GENERAL AREA OF WEAKLY BELOW NORMAL HEIGHTS ACROSS THE SOUTH AND NEAR THE GULF COAST. THIS IS CONSI- DERED REASONABLE... GIVEN THE RECENT HEAVY PRECIPITATION IN THAT GENERAL AREA. THE OFFICIAL HEIGHT PROG FOR TODAY CONSISTS OF 20 PERCENT OF TO- DAYS EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7... 20 PERCENT OF TODAYS GFS ENSEMBLE MEAN CENTERED ON DAY 8... 5 PERCENT OF TO- DAYS CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8... 10 PERCENT EACH OF TODAYS 0Z OPERATIONAL GFS RUN CENTERED ON DAY 8 AND YESTERDAYS OPERATIONAL 12 AND 18Z RUNS CENTERED ON DAY 7... 20 PERCENT OF TODAYS OPERATIONAL 6Z GFS RUN... AND 5 PERCENT OF TODAYS OPERA- TIONAL ECMWF RUN CENTERED ON DAY 7. MODEL OF THE DAY: NO STRONG PREFERENCE BUT ECMWF AND GFS ENSEMBLE MEANS GIVEN SLIGHTLY GREATER WEIGHTS DUE TO HAVING THE BEST 500 -HPA ANOMALY CORRELATIONS OVER NORTH AMERICA DURING THE PAST FEW MONTHS. FORECAST CONFIDENCE FOR THE 6 TO 10 DAY PERIOD IS BELOW AVERAGE TODAY... 2 ON A SCALE FROM 1 TO 5. THERE ARE MANY RELATIVELY SMALL INTER-MODEL DIFFERENCES WHICH WILL HAVE A SIGNIFICANT IMPACT ON THE FORECAST HEIGHT PROG. IN ADDITION... MOST OF TODAYS MODELS ARE SOMEWHAT DIFFERENT FROM WHAT WAS INDICATED YESTERDAY. SINCE THE OVERALL PATTERN IS RATHER ZONAL...TELECON- NECTIONS ARE NOT TOO HELPFUL SINCE THEY USUALLY WORK BEST WITH MORE AMPLIFIED WAVETRAINS. THE 6 TO 10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOGS TO THE 500-HPA BLENDED HEIGHT PROG. THE NEURAL NET SPECIFICATIONS DID NOT APPEAR REASONABLE INDICATING ANOMALOUS WARMTH OVER ALMOST THE ENTIRE CONUS. BIAS-CORRECTED 850-HPA TEMPERATURES FROM THE 0Z GFS WERE ALSO CONSIDERED. IT IS ALSO BASED ON THE CDC CALI- BRATED REFORECAST TEMPERATURE TOOL AND BIAS-CORRECTED MODEL OUTPUT FROM THE 0Z GFS AND THE GFS ENSEMBLE. THE 6 TO 10 DAY PRECIPITATION PROG IS BASED ON NEURAL NET SPECI- FICATIONS FROM THE BLENDED HEIGHT FIELD...ANALOGS TO THE 500-HPA BLENDED HEIGHT PROG...AND THE CDC CALIBRATED REFORECAST PRECIPI- TATION TOOL. . . . . . . . 8 TO 14 DAY OUTLOOK FOR JUNE 16 - 22 2004 DURING WEEK 2 THE 0Z OPERATIONAL GFS INDICATES A GENERAL PROGRES- SION OF THE PATTERN PREDICTED FOR THE 6-10 DAY PERIOD. THIS IS QUITE REASONABLE GIVEN THE RATHER ZONAL NATURE OF THE OVERALL PAT- TERN...BUT (AS USUAL) THE DIFFERENCES AMONG THE VARIOUS MODELS ARE EVEN GREATER DURING THE 8-14 DAY PERIOD THAN DURING THE 6-10 DAY PERIOD. THE ANOMALY FIELD OF THE GFS ENSEMBLE MEAN WAS QUITE WEAK OVERALL...ANOTHER INDICATION OF A LOT OF UNCERTAINTY AND RELATIVE- LY HIGH SPREAD AMONG THE INDIVIDUAL ENSEMBLE MEMBERS. THE OFFICIAL HEIGHT PROG FOR TODAY CONSISTS OF 30 PERCENT OF THE GFS ENSEMBLE MEAN CENTERED ON DAY 11... 15 PERCENT EACH OF THE 0Z GFS AND 06Z GFS CENTERED ON DAY 11... 15 PERCENT OF YESTERDAYS 18Z GFS CENTERED ON DAY 10... 10 PERCENT OF YESTERDAYS 12Z GFS CENTERED ON DAY 10... AS WELL AS 10 PERCENT OF TODAYS ECMWF ENSEM- BLE MEAN AND 5 PERCENT OF TODAYS ECMWF HIGH RESOLUTION RUN CENTER- ED ON DAY 7. FORECAST CONFIDENCE FOR THE 8 TO 14 DAY PERIOD IS BELOW AVERAGE ... 2 ON A SCALE OF 1 TO 5... PRIMARILY DUE TO A VERY WEAK ANOMALY PATTERN PREDICTED BY THE GFS ENSEMBLE MEAN... WHICH IS ORDINARILY THE BEST HEIGHT FIELD AT THE 814 DAY RANGE. THE 8 TO 14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN...NEURAL NET...AND ANALOG SPECIFICATIONS FROM THE OFFICIAL 500-HPA BLEND. IT IS ALSO BASED ON THE BIAS-CORRECTED 850-HPA TEMPERATURE ANOM- ALIES FROM THE 0Z GFS...AND THE CDC CALIBRATED REFORECAST TEMPER- ATURE TOOL. THE 8 TO 14 DAY PRECIPITATION PROG IS BASED ON THE CPC AND EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLE MEM- BERS... THE ANALOG TOOL AND NEURAL NET SPECIFICATIONS FROM THE OFFICIAL 500-HPA BLEND... AND THE BIAS CORRECTED PRECIPITATION FROM THE 0Z OPERATIONAL GFS. IT IS ALSO BASED ON THE CDC CALI- BRATED REFORECAST PRECIPITATION TOOL. 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 JUNE 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: 19880523 - 19960602 - 19880612 - 19870603 - 19850523 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: 19890615 - 19890612 - 19770531 - 19610523 - 19960601 6 to 10 day Outlook Table OUTLOOK FOR JUN 14 - 18, 2004 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N N OREGON N B NRN CALIF N B SRN CALIF A B IDAHO A B NEVADA A B W MONTANA A B E MONTANA A B WYOMING A B UTAH N B ARIZONA A B COLORADO N B NEW MEXICO N B N DAKOTA A B S DAKOTA A N NEBRASKA N N KANSAS N N OKLAHOMA N N N TEXAS N N S TEXAS N N W TEXAS N B MINNESOTA A N IOWA A A MISSOURI N N ARKANSAS N A LOUISIANA B A WISCONSIN A A ILLINOIS N A MISSISSIPPI B A MICHIGAN N A INDIANA N A OHIO N A KENTUCKY N A TENNESSEE N A ALABAMA B A NEW YORK N A VERMONT N N NEW HAMP N N MAINE N N MASS N N CONN N N RHODE IS N N PENN N A NEW JERSEY N A W VIRGINIA N A MARYLAND N A DELAWARE N A VIRGINIA N A N CAROLINA N A S CAROLINA N N GEORGIA B N FL PNHDL B A FL PENIN N N AK N SLOPE N B AK ALEUTIAN B A AK WESTERN N N AK INT BSN N B AK S INT B N AK SO COAST B A AK PNHDL N N 8 to 14 day Outlook Table OUTLOOK FOR JUN 16 - 22, 2004 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B A OREGON B A NRN CALIF B N SRN CALIF N B IDAHO N N NEVADA N N W MONTANA N N E MONTANA N N WYOMING N B UTAH N B ARIZONA N B COLORADO A B NEW MEXICO A B N DAKOTA A A S DAKOTA A A NEBRASKA A N KANSAS A N OKLAHOMA A N N TEXAS A N S TEXAS A N W TEXAS A B MINNESOTA A A IOWA A A MISSOURI A N ARKANSAS A N LOUISIANA N A WISCONSIN A A ILLINOIS A A MISSISSIPPI B A MICHIGAN A A INDIANA N A OHIO N A KENTUCKY N A TENNESSEE B A ALABAMA B A NEW YORK N N VERMONT N N NEW HAMP N N MAINE N N MASS N N CONN N N RHODE IS N N PENN N N NEW JERSEY N N W VIRGINIA N N MARYLAND N N DELAWARE N N VIRGINIA N N N CAROLINA N B S CAROLINA N N GEORGIA N N FL PNHDL B N FL PENIN N B AK N SLOPE A B AK ALEUTIAN B A AK WESTERN N A AK INT BSN A B AK S INT N N AK SO COAST B A AK PNHDL N 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. $$