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>From: Robert Mullenax <rmullenax@xxxxxxxxxxxx> >Organization: Universal Weather >Keywords: 200203221710.g2MHA4a16666 Robert, Christian, et. al., The upcoming MRF replacement seems to be a popular topic today: Robert wrote: >I think this question has been answered before here, but I can't seem to >find it if it has. >With all of the changes going on with the AVN/MRF, what will be transmitted >on NOAAPORT. >I know the 384 hour data will not be on NOAAPORT, but will it still be the >AVN 4 times a day out to 120 hours >and then one MRF-like run out to 240? > >Thanks, and I apologize if this has been answered already. Christian wrote: >I just read again that MRF will be phased out. >So, what will we receive through LDM? >I would want to know which AVN grids will be send out in details (horizontal >resolution, coverage, forecast hours, pqact.conf requests to get them) so that >I can migrate all my MRF-related jobs to the AVN after the switch at the end of >April. Several items related to the MRF and AVN changes have been posted to the nws-changes email list in the past couple of months. These messages are generated by the NWS and sent in the NOAAPORT NWSTG stream. A short "archive" of these messages are also maintained on an NWS web site: http://www.nws.noaa.gov/chgnot.shtml The following is the set of notices that have been included in the nws-changes list since the beginning of February: From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx> Date: Mon, 11 Feb 2002 07:55:16 -0700 To: nws-changes@xxxxxxxxxxxxxxxx Subject: 20020211: model changes-(fwd) SUBJECT: Changes to the NWS Production Suite A series of changes to the NCEP global model are planned for this Spring. A tentative date of 5 March 2002 has been set to increase the forecast length of the global AVN model to 384 hours. This model currently produces a 126 hour forecast at 00Z and 12Z and an 84 hour forecast at 06Z and 18Z. A tentative date of 2 April 2002 has been set to replace the 00Z MRF model with the 00Z AVN. Look-alike grids for the MRF will be created and disseminated from the 00Z AVN. These look alike grids will be available until 1 October 2002. Finally, in early May the resolution of the NCEP global model will be increased from T170L42 to T254L64. The NCEP quarterly backup test which had been rescheduled for 14 February 2002 has now been canceled. A new test date in March will be announced as soon as it becomes available. Item 42, which had been withdrawn at 19Z on 1 February 2002 due to a problem with processing graphics in the new G3 format, will be re-implemented at 12Z on 12 February 2002. On Tuesday, 5 February 2002, NCEP discontinued dissemination of all its AFOS products. The production of these products on the NCEP supercomputer will be discontinued on 12 March 2002. On Tuesday, 19 March 2002, changes will be made to the BUFR data stored on the NCEP supercomputer. Please see the bottom of this memo for more information. A list of the major model implementations planned for 2002 can be found at: http://www.ncep.noaa.gov/NCO/PMB/changes As additional information about each implementation becomes available, links will be added on the change summary page. * * * * * * * * * * * * * * * * * * * * * * * * * * * * From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx> Date: Wed, 27 Feb 2002 07:15:32 -0700 To: nws-changes@xxxxxxxxxxxxxxxx Subject: 20020225: AVN-ADMIN NOTICE NOXX10 KWBC (fwd) 300 NOXX10 KWBC 252103 DATA MGT MESSAGE 02-02.12 TO AWIPS/NOAAPORT USERS... FAMILY OF SERVICES /FOS/ SUBSCRIBERS EMERGENCY MANAGERS WEATHER INFORMATION NETWORK /EMWIN/NATIONAL WEATHER SERVICE /NWS/ CUSTOMERS... WAFS USERS... GTS USERS... NWS FAX CHART USERS FROM RTH WASHINGTON DATA MANAGEMENT EFFECTIVE MARCH 27... 2002... FORECAST DATA FROM ALL FOUR RUNS OF THE AVN MODEL WILL BE AVAILABLE OUT TO 384 HOURSON THE NWS FTP SERVERS. THIS WILL NOT AFFECT MESSAGES SENT TO COMMUNICATIONS LINES OR BROADCASTS. THESE RUNS WILL BE MADE AT T170L42 RESOLUTION /APPROXIMATELY 1 DEGREE HORIZONTAL RESOLUTION/ OUT TO 180 HOURS WITH OUTPUT IN 3- HOUR INCREMENTS. FROM 192 TO 384 HOURS THE RESOLUTION OF THESE RUNS WILL BE REDUCED TO T62L28 /APPROXIMATELY 2.5 DEGREE HORIZONTAL RESOLUTION/ WITH OUTPUT IN 12-HOUR INCREMENTS. THE FOLLOWING DIRECTORIES ON THE NWS FTP SERVERS WILL BE AFFECTED BY THIS CHANGE /SL.US008001/ST.OPNL/MT.AVN/UNDERSCORE/CY.HH/RD.YYYYMMDD/ PT.GRID/UNDERSCORE/DF.GR1. THIS DIRECTORY CONTAINS TWO MAIN FILE TYPES... A 3-D GRIB FILE AND A GRIB FILE OF SURFACE FLUXES... PLUS THEIR INDEX FILES. AT 12 UTC A MUCH REDUCED GRID AT 2.5 DEGREE RESOLUTION IS ALREADY AVAILABLE OUT TO 120 HOURS... BUT THIS IS A RELATIVELY SMALL FILE COMPARED TO THE OTHERS. THE APPROXIMATE DATA VOLUME CHANGE IN THIS DIRECTORY ARE AS FOLLOWS CURRENTLY 1445 MB OF DATA ARE STORED AT BOTH 00 AND 12 UTC.. AND 975 MB AT BOTH 06 AND 18 UTC FOR A GRAND TOTAL OF ABOUT 4.8 GB PER DAY. THIS IMPLEMENTATION WILL ADD 690 MB OF DATA AT BOTH 00 AND 12 UTC AND 1160 MB AT 06 AND 18 UTC WHICH WILL BRING THE TOTAL TO 2135 MB PER CYCLE OR 8.5 GB PER DAY. THE APPROXIMATE AVAILABILITY TIMES OF THESE NEW DATA SETS ARE AS FOLLOWS 00 UTC FORECAST HOUR 129 - 384 AVAILABLE STARTING 0400 UTC WITH FINAL PRODUCT AVAILABLE 30 MINUTES LATER 06 UTC FORECAST HOUR 87 - 384 AVAILABLE STARTING 0945 UTC WITH FINAL PRODUCT AVAILABLE 50 MINUTES LATER 12 UTC FORECAST HOUR 129 - 384 AVAILABLE STARTING 1600 UTC WITH FINAL PRODUCT AVAILABLE 30 MINUTES LATER. 18 UTC FORECAST HOUR 87 - 384 AVAILABLE STARTING 2145 UTC WITH FINAL PRODUCT AVAILABLE 50 MINUTES LATER. PLEASE NOTE THAT THERE ARE CURRENTLY NO PLANS TO DISSEMINATE THESE ADDITIONAL DATA ANYWHERE EXCEPT FOR THE NWS AND NCEP FTP SERVERS. FOR FOS/NOAAPORT AND NON-AWIPS CUSTOMERS - IF YOU HAVE ANY QUESTIONS REGARDING THIS NOTICE... PLEASE CONTACT DATA MANAGEMENT LOWER CASE EMAIL NWS.DM/AT SYMBOL//NOAA.GOV THIS INFORMATION IS ALSO POSTED ON THE NWS DATA MANAGEMENT CHANGE NOTICES WEB PAGE THE URL IS LISTED BELOW HTTP/COLON///WWW.NWS.NOAA.GOV/DATAMGMT/NOTICES.SHTML DATA MANAGEMENT TELECOMMUNICATION OPERATIONS CENTER RTH WASHINGTON SENDS From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx> Date: Thu, 28 Feb 2002 06:30:35 -0700 To: nws-changes@xxxxxxxxxxxxxxxx Subject: 20020228: Global Fcst chgs-ADMIN NOTICE NOXX10 KWBC (fwd) 066 NOXX10 KWBC 281241 DATA MGT MESSAGE 02-02.15 TO AWIPS/NOAAPORT USERS... FAMILY OF SERVICES /FOS/ SUBSCRIBERS EMERGENCY MANAGERS WEATHER INFORMATION NETWORK /EMWIN/NATIONAL WEATHER SERVICE /NWS/ CUSTOMERS... WAFS USERS... GTS USERS... NWS FAX CHART USERS FROM RTH WASHINGTON DATA MANAGEMENT SUBJECT UPCOMING CHANGES TO THE NCEP GLOBAL FORECAST SYSTEM IN LATE WINTER AND SPRING OF 2002... NCEP WILL BE MAKING SEVERAL CHANGES TO ITS GLOBAL FORECAST SYSTEM /GFS/. THE NCEP GFS INCLUDES THE MRF... THE AVN... AND THE GLOBAL DATA ASSIMILATION SYSTEM /GDAS/... WHICH IS ALSO KNOWN AS THE FNL. CURRENTLY THE MRF RUN OF THE GFS IS RUN ONCE PER DAY AT 00 UTC. THE RESOLUTION OF THE MRF IS T170L42 /75 KM HORIZONTAL/ OUT TO 168 HOURS AND T62L28 /210 KM HORIZONTAL/ RESOLUTION FROM 180 TO 384 HOURS. OUTPUT ARE MADE AVAILABLE FROM THE MRF IN 12-HOUR INCREMENTS. THE AVN RUN OF THE GFS IS CURRENTLY RUN FOUR TIMES PER DAY AT T170L42 RESOLUTION. AT 00 AND 12 UTC THE AVN PRODUCES FORECAST OUT TO 126 HOURS AND AT 06 AND 18 UTC IT PRODUCES FORECASTS TO 84 HOURS. ALL FOUR RUNS OF THE AVN PRODUCE OUTPUT IN 3-HOUR INCREMENTS. THE GDAS RUN OF THE GFS IS RUN FOUR TIMES PER DAY AT BOTH T170L42 AND T62L28 RESOLUTIONS AND PRODUCES A NINE HOUR FORECAST THAT IS USED AS INPUT INTO THE NEXT RUN OF THE AVN AND FNL. THE FIRST CHANGE TO THE NCEP GFS HAS BEEN TENTATIVELY SCHEDULED FOR 5 MARCH 2002. ON THIS DATE THE LENGTH OF ALL FOUR RUNS OF THE AVN WILL BE INCREASED TO 384 HOURS. THESE RUNS WILL BE MADE AT T170L42 RESOLUTION OUT TO 180 HOURS WITH OUTPUT IN 3-HOUR INCREMENTS. FROM 192 TO 384 HOURS THE RESOLUTION OF THESE RUNS WILL BE REDUCED TO T62L28 WITH OUTPUT IN 12-HOUR INCREMENTS. THERE ARE CURRENTLY NO PLANS TO DISSEMINATE THESE ADDITIONAL DATA ANYWHERE EXCEPT FOR THE NWS AND NCEP FTP SERVERS. PLEASE NOTE THAT THIS IMPLEMENTATION WILL NOT CHANGE ANY OF THE EXISTING AVN PRODUCTS ALREADY BEING DISSEMINATED FROM NCEP. AFTER THIS IMPLEMENTATION THE NEXT CHANGE TO THE NCEP GFS IS TENTATIVELY SCHEDULED FOR 23 APRIL 2002. ON THIS DATE THE MRF RUN WILL BE DISCONTINUED. NCEP WILL CREATE AND DISSEMINATE MRF LOOK ALIKE GRIB FILES FROM THE 00 UTC AVN RUN. THESE LOOK ALIKE GRIB FILES WILL BE CREATED FOR APPROXIMATELY 6 MONTHS WHICH WILL ALLOW USERS OF THESE PRODUCTS TIME TO TRANSITION TO THE EXTENDED AVN RUNS. NCEP WILL MAKE THESE LOOK ALIKE GRIB FILES AVAILABLE UNDER TEST DIRECTORIES ON THE NWS AND NCEP FTP SERVERS SHORTLY AFTER THE EXTENSION OF THE AVN IS IMPLEMENTED ON 5 MARCH 2002. FINALLY... PENDING CAFTII APPROVAL IN MARCH 2002... THE RESOLUTION OF THE GFS WILL BE INCREASED TO T256L64 /55 KM HORIZONTAL/ RESOLUTION. THIS IMPLEMENTATION DATE HAS BEEN TENTATIVELY SCHEDULED FOR SOMETIME IN MAY 2002. MORE DETAILS ON THIS IMPLEMENTATION WILL BE FORTHCOMING AFTER CAFTII APPROVAL. NCEP APPRECIATES YOUR PATIENCE AS WE TRANSITION TO A BETTER GFS. FOR FOS/NOAAPORT AND NON-AWIPS CUSTOMERS - IF YOU HAVE ANY QUESTIONS REGARDING THIS NOTICE... PLEASE CONTACT DATA MANAGEMENT LOWER CASE EMAIL NWS.DM/AT SYMBOL//NOAA.GOV THIS INFORMATION IS ALSO POSTED ON THE NWS DATA MANAGEMENT CHANGE NOTICES WEB PAGE THE URL IS LISTED BELOW HTTP/COLON///WWW.NWS.NOAA.GOV/DATAMGMT/NOTICES.SHTML DATA MANAGEMENT TELECOMMUNICATION OPERATIONS CENTER RTH WASHINGTON SENDS From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx> Date: Mon, 04 Mar 2002 15:47:15 -0700 To: nws-changes@xxxxxxxxxxxxxxxx Subject: 20020304: avn/mrf merger (fwd) To: Hualu Pan <Hualu.Pan@xxxxxxxx> Subject: avn/mrf merger All, There is a change to the AVN/MRF suite which will be transparent to all users in the beginning but is the first step of a process NCEP is taking to simplify the runs of the NCEP global model. What will happen for the 12Z run on 5 March 2002 is that the AVN runs will be extended to the same length as the MRF runs (out to 384 hours). While people who directly download the GRIB files will benefit immediately to this change, it will eventually affect all people who use the MRF forecasts. As the AVN forecasts have become more popular, there is more demand on the length of the forecast. We currently run the AVN to 126 hours at 00Z and 12Z and to 84 hours at 06Z and 18Z. The weather service is going toward 4-times daily update of weather to seven days both for the NCEP service centers but also to the WFOs. Given that the MRF runs high resolution forecasts to seven days and low resolution to 16 days, the extension of the AVN beyond five days would make the MRF product duplicating the AVN for the most part (the low resolution part of the MRF uses much less resource compared to the high resolution part). We compared the AVN forecasts and the MRF forecasts for one whole year to determine if replacing the MRF forecasts with the AVN forecasts will degrade the forecast skill and we found that the skills of the two forecasts are practically the same. The only difference between the AVN forecast and the MRF forecast is that we wait 2 hours and 45 minutes for observations to arrive at NCEP before starting the AVN runs and 6 hours for the MRF. Since we start both forecasts with the best first guess from our global data assimilation system, this one-time difference in the cutoff time is not crucial to the forecast skill (the explanation would take too much space here). Furthermore, we will be issuing the 06Z AVN not long after the normal MRF forecasts are issued. The later forecasts are usually better than the earlier ones. For NCEP, once we start to issue AVN forecasts to seven days, it makes no sense to keep the MRF. It also makes little difference if we extend the AVN to 16 days in low resolution. Many people would ask if we have any skill credential to issue two week forecasts every six hours. Our strategy is to make these forecasts part of our ensemble strategy. Given that week-two forecasts can only be used as outlooks and the skill of any individual forecast is very low, we can only hope to use the ensemble strategy to provide information about the atmosphere regimes. Running all the ensemble at 00z or running them at 4 different times are just different strategies. Later this year when we get more computer resource, we plan to run the global ensemble four times daily with ten members per run (a doubling of our ensemble members). As for the MRF, we plan to stop running that in April. We will make all the files currently made by MRF from the 00Z AVN runs so users will not be inconvinienced and will have lots of time to change over to the AVN products. Finally, there has been a lot of confusions about the names AVN and MRF. By streamlining the forecasts to one single suite, we hope to reduce that confusion. We plan to rename our forecast suite from AVN to the Global Forecast System (GFS) at a later time and we will provide ample lead time before we make the change. Please feel free to write to me with any question you may have about this change. Hua-Lu Pan From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx> Date: Fri, 15 Mar 2002 13:54:15 -0700 To: nws-changes@xxxxxxxxxxxxxxxx Subject: 20020315: Global models March 15, 2002 MEMORANDUM FOR: Distribution E FROM: John H. Ward Chief, Production Management Branch SUBJECT: Changes to the NWS Production Suite A series of changes to the NCEP global model are planned for this Spring. On Tuesday, 5 March 2002, at 12Z the forecast length of the global AVN model was increased to 384 hours for all four cycles. These extended forecast data are currently available on the NCEP ftp server at: ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/avn/prod/. On 27 March 2002 these data will become available on the NWS ftp server at: ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/. A tentative date of 23 April 2002 has been set to replace the 00Z MRF model with the 00Z AVN. Look-alike grids for the MRF will be created and disseminated from the 00Z AVN. These look- alike grids will be available through Fall 2002. NCEP is currently making these look alike grids in parallel production. These data are available on the NCEP ftp server at: ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/mrf/para/. Finally, in early June the resolution of the NCEP global model will be increased from T170L42 to T254L64. The change in resolution of the RUC model from 40 km to 20 km originally scheduled for Tuesday, 9 April at 12Z has been rescheduled for Tuesday, 16 April at 12Z. There will be no change in the forecast grids being disseminated via AWIPS or Family of Services. A Real-Time Test and Evaluation of the 20 Km RUC began on 8 March. Test data is available on the NCEP ftp server at: ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/ruc/para/. Advertised changes to the BUFR data stored on the NCEP supercomputer originally planned for 19 March, have been postponed to 26 March to allow for further testing. Please see the bottom of this memo for more information. The next NCEP quarterly backup test has been scheduled for the 00Z cycle on 4 April 2002 (1900 EST 03 April 2002). If the weather situation prohibits this test, it will be attempted on 11 April 2002. A list of the major model implementations planned for 2002 can be found at: http://www.nco.ncep.noaa.gov/pmb/changes As additional information about each implementation becomes available, links will be added on the change summary page. To unsubscribe from the JIF memo use the link provided at: http://www.nco.ncep.noaa.gov/pmb/jifmemo/ * * * * * * * * * * * * * * * * * * * * * * * * * * * * This is all of the information that we (Unidata) have on the MRF/AVN changes. I hope that this helps... Tom -- +-----------------------------------------------------------------------------+ * Tom Yoksas UCAR Unidata Program * * (303) 497-8642 (last resort) P.O. Box 3000 * * yoksas@xxxxxxxxxxxxxxxx Boulder, CO 80307 * * Unidata WWW Service http://www.unidata.ucar.edu/* +-----------------------------------------------------------------------------+
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