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>From: "Margarita Mihailidi" <address@hidden> >Organization: CCNY >Keywords: 200512221446.jBMEkf7s000741 IDD NNEXRAD McIDAS ADDE Hi Margarita, re: >Thank a lot for the detailed information. May be you can answer my specific >question. Do you have level IV NEXRAD data in binary or text format (may be >archived)that we could import into research models in matlab or other home >made software (C++, ...) ? Sorry for not being more explicit in my last email. Since I was not familiar with 'NEXRAD Level IV' I did a quick Google (tm) search and found the following definition: http://www.ncdc.noaa.gov/oa/radar/nexradterms.html LEVEL IV DATA: The archive Level IV interface is located at the PUP. Any data or information available at the PUP may also be recorded on SCSI tape or WORM Optical disk at the discretion of the PUP operator. These Level IV data are generally for local use and are not permanently archived at NCDC. We do not have access to or distribute NEXRAD Level IV data. The realtime Level III data available from the NWS through NOAAPORT is the type of NEXRAD data that we have been distributing in the IDD for a number of years: http://www.ncdc.noaa.gov/oa/radar/nexradterms.html LEVEL III DATA: The archive Level III interface is located at the RPG. A set of pre-determined products defined in FMH-11 part A, comprise the Level III data which is archived on WORM Optical Disk and sent to NCDC for permanent storage. LEVEL II DATA: The archive Level II interface is also located at the RDA. The Level II data are digital base data output from the signal processor and include base reflectivity, mean radial velocity and spectrum width. The output also includes information on synchronization, calibration, date, time, antenna position, and operational mode. Level II data are recorded on 8 mm magnetic tape and sent to NCDC for permanent storage. The NWS adopted the use of the Unidata LDM/IDD to collect and distribute the full volume scan NEXRAD Level II data. The comment about the Level II data being recorded on 8 mm magnetic tape and sent to the National Climactic Data Center (NCDC) is now archaic. Both Level II and Level III data are in the standard binary formats that are used by the National Weather Service and are available from the NCDC. Given the definition of Level IV data found on the NCDC site, They are apparently not the kind/format of data you are looking for. Whether or not Level II/III data can be imported "as is" into research models in Matlab or other software I can not say as this would depend on the import capability of the model/package in question. I believe, however, that the NWS now uses the Level II data in their modeling efforts. >Thanks again. No worries. Cheers, Tom Yoksas -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.