NOUS41 KWBC 091850 PNSWSH TECHNICAL IMPLEMENTATION NOTICE 07-89 NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC 150 PM EST FRI NOV 9 2007 TO: FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER WIRE SERVICE /NWWS/ SUBSCRIBERS...EMERGENCY MANAGERS WEATHER INFORMATION NETWORK /EMWIN/ SUBSCRIBERS... NOAAPORT SUBSCRIBERS...OTHER NATIONAL WEATHER SERVICE /NWS/ PARTNERS AND OTHER USERS...NWS EMPLOYEES FROM: PAUL HIRSCHBERG CHIEF...SCIENCE PLANS BRANCH OFFICE OF SCIENCE AND TECHNOLOGY /OST/ SUBJECT: UPGRADE TO SHORT RANGE ENSEMBLE MODELING SYSTEM: EFFECTIVE DECEMBER 11 2007 EFFECTIVE TUESDAY DECEMBER 11 2007...AT 1500 COORDINATED UNIVERSAL TIME /UTC/...THE NATIONAL CENTERS FOR ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE SHORT RANGE ENSEMBLE MODELING SYSTEM /SREF/. MODELING SYSTEM CHANGES: - BIAS CORRECTED FIELDS WILL BE PRODUCED FOR ALL COMPONENTS/ MEMBERS. EACH BIAS CORRECTION IS COMPUTED USING A DECAYING AVERAGE APPROACH WHERE HIGHER WEIGHT IS GIVEN TO THE MORE RECENT FORECAST. A SEPARATE BIAS CORRECTION IS COMPUTED AT EACH GRID POINT AND APPLIED TO EACH OF THE 21 SREF MEMBERS, FOR EACH CYCLE...03Z...09Z...15Z AND 21Z...FOR EACH FORECAST LEAD TIME ...3 HOURLY OUT TO 87 HOURLY. ALL ENSEMBLE PRODUCT GENERATION USES THESE BIAS CORRECTED MEMBERS. THE APPLICATION OF THE PROCEDURE RESULTS IN SIGNIFICANTLY LOWER ERRORS AND BETTER BEHAVED PROBABILITIES. - THE DOMAIN OF RSM MEMBERS WILL BE EXPANDED TO COVER MORE AREA WEST OF ALASKA COVERED BY THE OTHER MEMBERS. - FOUR NEW AVIATION PRODUCTS WILL BE ADDED: -ICING -CLEAR AIR TURBULENCE -LOW LEVEL CEILING -FLIGHT RESTRICTION - ADD BUFR OUTPUT FROM SIX WRF MEMBERS A LIST OF BIAS CORRECTED FIELDS IS AVAILABLE. PLEASE SEE THE FOLLOWING WEBSITE FOR MORE INFORMATION: /USE LOWERCASE LETTERS/ HTTP://WWW.NCO.NCEP.NOAA.GOV/PMB/CHANGES/SREF- 12_11_2007_BIASCORRECTEDFIELDS.HTML PARALLEL DATA SETS FOR THE CURRENT PRODUCTS AND BIAS CORRECTED PRODUCTS ARE AVAILABLE ON THE NCEP FTP SERVER AT THE LINK BELOW. NCEP ENCOURAGES ALL USERS TO EVALUATE THESE DATA SETS TO ENSURE THAT THEIR SYSTEMS ARE PREPARED FOR THE UPCOMING CHANGE. /USE LOWERCASE LETTERS/ FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/SREF/PARA/SREF.YYYYM MDD/HH THE ENVIRONMENTAL MODELING CENTER /EMC/ HAS A PUBLICLY AVAILABLE WEB SITE WHICH CAN PROVIDE USERS MORE INFORMATION CONCERNING THE SREF MODELING SYSTEM AS WELL AS ALL OTHER NCEP MODELING SYSTEMS. /PLEASE USE LOWERCASE LETTERS/ HTTP://WWW.EMC.NCEP.NOAA.GOV DATA DELIVERY TIMING/VOLUME/CONTENT CHANGES: NOAAPORT DATA: - AT THE CURRENT TIME...THE FOLLOWING DOMAINS ARE DISSEMINATED TO NOAAPORT/AWIPS USERS: CONUS...ALASKA...EASTERN PACIFIC. - NO DATA CONTENT CHANGES ARE EXPECTED. - NO CHANGE IS EXPECTED IN THE CONTENT DELIVERY TIME. - NO SIGNIFICANT CHANGES IN DATA VOLUMES ARE EXPECTED. - NO CHANGE IN PDS CONTENT IS EXPECTED. NWS FTP SERVER: /USE LOWERCASE LETTERS/ EXCEPT FOR THE SL...ST...MT AND CY. THE HH REFERS TO THE CYCLE: 03...09...15...21. THE YYYYMMDD REFERS TO THE CURRENT DATE. FTP://TGFTP.NWS.NOAA.GOV/SL.US008001/ST.OPNL/MT.SREF_CY.HH/RD.YYY YMMDD - THE CONUS DOMAIN IS CURRENTLY DISSEMINATED. - NO DATA CONTENT CHANGES ARE EXPECTED. - NO CHANGE IS EXPECTED IN THE CONTENT DELIVERY TIME. - NO SIGNIFICANT CHANGES IN DATA VOLUMES ARE EXPECTED. - NO CHANGE IN PDS CONTENT IS EXPECTED. NCEP FTP SERVER: /USE LOWERCASE LETTERS/ - AT THE CURRENT TIME...THE FOLLOWING DOMAINS ARE DISSEMINATED: FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/SREF/PROD NCEP FTP SERVER USERS: CONUS...ALASKA...EASTERN PACIFIC NWS FTP SERVERS USERS: CONUS - NO CHANGE IS EXPECTED IN THE CONTENT DELIVERY TIME. - NO CHANGE IN PDS CONTENT IS EXPECTED FOR THE CURRENT DATA SETS WHICH ARE DELIVERED. - NO SIGNIFICANT CHANGES IN DATA VOLUMES ARE EXPECTED FOR THE DATA SETS WHICH ARE CURRENTLY DELIVERED. - THE DIRECTORY STRUCTURE WILL CHANGE SIGNFICANTLY FOR THE SREF OUTPUT WHICH IS CURRENTLY DISSEMINATED. THE CYCLES WILL BE SEPARATED INTO THEIR OWN SUBDIRECTORIES INSTEAD OF RESIDING IN ONE SUBDIRECTORY. PLEASE SEE THE PARALLEL DATA SETS FOR AN EXAMPLE OF THE NEW DIRECTORY PATH. THE NEW FORMAT WILL BE AS FOLLOWS:/USE LOWERCASE LETTERS/ MAIN/PARENT DIRECTORY STRUCTURE: FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/SREF/PROD CURRENT SUBDIRECTORY STRUCTURE SREF.YYYYMMDD NEW SUBDIRECTORY STRUCTURE SREF.YYYYMMDD/HH/PGRB - INDIVIDUAL MEMBER GRIB1/GRIB2 DATA SETS SREF.YYYYMMDD/HH/ENSPROD - MEAN/SPREAD/PROB GRIB1/GRIB2 DATA SETS - NEW BIAS CORRECTED DATA SETS WILL BECOME AVAILABLE ON THE NCEP FTP SERVER. THESE DATA SETS WILL BE DELIVERED APPROXIMATELY 60 MINUTES AFTER THE NON-BIAS CORRECTED DATA SETS. MAIN DIRECTORY STRUCTURE: FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/SREF/PROD SUBDIRECTORY STRUCTURE SREF.YYYYMMDD/HH/PGRB_BIASC - INDIVIDUAL MEMBER GRIB1/GRIB2 DATA SETS SREF.YYYYMMDD/HH/ENSPROD_BIASC - MEAN/SPREAD/PROB GRIB1/GRIB2 DATA SETS NCEP ENCOURAGES USERS TO ENSURE THEIR DECODERS ARE FLEXIBLE AND ARE ABLE TO ADEQUATELY HANDLE CHANGES IN CONTENT ORDER ...PARAMETER FIELDS CHANGING ORDER...CHANGES IN THE SCALING FACTOR COMPONENT WITHIN THE PDS OF THE GRIB FILES AND ANY VOLUME CHANGES THAT MAY BE FORTHCOMING. THESE ELEMENTS MAY CHANGE WITH FUTURE NCEP MODEL IMPLEMENTATIONS. NCEP WILL MAKE EVERY ATTEMPT TO ALERT USERS TO THESE CHANGES BEFORE IMPLEMENTATION. FOR QUESTIONS REGARDING THE SCIENTIFIC CONTENT OF THE MODELING SYSTEM...PLEASE CONTACT: GEOFF DIMEGO NCEP/EMC CAMP SPRINGS MD 20746 PHONE: 301-763-8000X7221 EMAIL: GEOFF.DIMEGO@NOAA.GOV FOR QUESTIONS REGARDING THE DATAFLOW ASPECTS OF THESE DATA SETS...PLEASE CONTACT THE NCEP/NCO/PMB DATAFLOW HELP DESK EMAIL ADDRESS BELOW. /USE LOWERCASE LETTERS FOR THE FOLLOWING PORTION OF THE EMAIL ADDRESS BELOW/: /ATAFLOW/ EMAIL: NCEP.PMB.DATAFLOW@NOAA.GOV THIS NOTICE AND OTHER TECHNICAL IMPLEMENTATION NOTICES ARE AVAILABLE ONLINE AT /USE LOWER CASE LETTERS/: HTTP://WWW.NWS.NOAA.GOV/OM/NOTIF.HTM $$ NNNN