This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
>From: "Salottolo Greg" <address@hidden> >Organization: NTSB >Keywords: 200601101502.k0AF0j7u027285 McIDAS station database Hi Greg, First, I hope that your holiday season was fun! re: NEXRAD stations are listed with 3-letter station IDs >Thanks Tom. I understand now. I believe the origins of this go back to the original listings of NEXRAD stations/locations by the NWS where I the first listings used 3-letter station IDs. I am pretty confident in this since I am the one that modified McIDAS to support display of NEXRAD Level III images. >However, greater precision in other locations would be useful. I agree completely. >Another question when do an imgdisp id=lwx does the command use radar >coordinates dd:min:sec to locate the radar antenna? Yes, it should. IMGDISP parses the STAtion= keyword and then uses the ID value in a STNDB.CORE, STNDB.SITE, and STNDB.USER lookup (with STNDB.USER being the most significant; locations specified in it override specifications in STNDB.SITE which, in turn, override locations specified in STNDB.CORE). The effect is the same as if one uses STNLIST to get the location. >Was there a time when the nexrad coordinates used by the imgdisp command >only used dd:min? Yes, there was a time when the NEXRAD locations were inaccurate and/or incorrect. This was brought to light by IDV users (probably you?) and reported to SSEC. The result was an updating of the STNDB.CORE with correct and more precise NEXRAD locations. >We have in the past noticed mcidas generated wx echo displays >(from NEXRALL) that were displaced by a small distance (comparing >with WATADS presentation). You noticed this by locating the NEXRAD station on top of the composite display? If yes, then the previously inaccurate/bad (some were totally incorrect) locations would make a significant difference. >I know we had a range ring location >issue with IDV because of a lack of precision. That has been fixed. > >Thanks .. No worries. Cheers, Tom -- +-----------------------------------------------------------------------------+ * Tom Yoksas UCAR Unidata Program * * (303) 497-8642 (last resort) P.O. Box 3000 * * address@hidden Boulder, CO 80307 * * Unidata WWW Service http://www.unidata.ucar.edu/* +-----------------------------------------------------------------------------+