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NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
Hi everyone. Back last year Gilbert Sebenste over at Northern Illinois University created a dedicated EMWIN server for backup should NOAAPORT go down and you need a backup source of watches/warnings and other test products. I've been a user of EMWIN for 7 years now, and come to rely on it for watches/warnings. However, just like Noaaport, sometimes it goes down. So I started using the combination of two different EMWIN downlinks (goes and Ku) with the IDS/DDPLUS for 2 years now. Special thanks to Gerry Creager at Texas A&M for providing me with the feed of data back then. It essentially means that in the past two years I've never missed a watch/warning for my SMS/SNPP alerting system and website (http://www.aprsfl.net). Gilbert and I were discussing EMWIN the other day, as he was gracious enough to provide me an alternate back feed for IDS/DDPLUS to compliment the Texas A&M feed, and I started thinking about how he's doing it. He's currently using FTP on his dedicated box to pull in EMWIN every 2 minutes from WALLOPS, the GOES/EMWIN uplink facility. I've worked with Santos Rodriguez for years with EMWIN dissemination of these products, and work heavily with our local WFO with Skywarn participation. At any rate, I got thinking, it can't be that hard to get the data from the Windows EMWIN app and run pqinsert to get it into an experimental feed on my LDM box. My system here (remember, I'm a serious weather hobbyist) is an 8 core box running VMWare ESX (I own an ISP business here in Tampa). WxMesg (EMWIN software http://www.wxmesg.com) runs Windows 2003 on one VM, and CentOS run a different VM for LDM. (Along with others for my local personal weather station, etc) So using Samba/SMB file sharing, I setup WxMesg to additionally drop the products from the satellite ingest software into a directory that is viewable over on the LDM server. I wrote a quick dirty wrapper as a service that is always watching that directory, and calls up PQinsert when it finds a new file. Getting the WMO headers 100% right looked to be something of a long process though. But then Gilbert provided me with a copy of the GNU script that he is using to do EMWIN via FTP so I can see how he's doing it. That script was written by Stonie Cooper from Planetary Data, Inc and I have to give him huge credit here on this part of the project. A huge percentage of that script was devoted to the FTP process. But since I didn't need that, I took just the file parsing portion of his script, and married it with my wrapper daemon. When a file is detected, it spawns off the portion of his script that processes the files and inserts them into the EXP dataset on my LDM box. Data inserted from both of my EMWIN downlink dishes comes onto the LDM looking as the following (from ldmadmin watch) in real time: Mar 12 17:15:50 pqutil INFO: 16384 20080312171550.070 EXP 999 EMWIN F/TRKNEPUS.GIF Mar 12 17:16:35 pqutil INFO: 1293 20080312171635.752 EXP 999 EMWIN WWUS73 KGLD 121716 /pNPWGLD Mar 12 17:16:35 pqutil INFO: 1289 20080312171635.868 EXP 999 EMWIN WWUS73 KGLD 121716 /pNPWGLD Mar 12 17:17:02 pqutil INFO: 205 20080312171702.576 EXP 999 EMWIN SXVD01 PANC 121712 /pPLSANC Mar 12 17:17:03 pqutil INFO: 55296 20080312171702.679 EXP 999 EMWIN F/SAHOURLY.ZIS Tom Yoksas was the one who suggested that I put "EMWIN " in the front of the product, making it easier to work with in pqact. Full details of all the products offered on the EMWIN stream are available at http://www.weather.gov/emwin/windat.htm . I have plenty of spare bandwidth, and am multihomed on the net with multiple carriers, and also have native IPv6 on my network. I'm offering this feed to anyone who would like to pick it up as my way of saying thanks to the Unidata community for helping me out with the products you guys provide me that assists with what I do with Skywarn here in West Central Florida. This data has less than a 1 second delay from when the file is written off the satellite receiver till it's in the queue, its VERY real time. Normal disclaimer applies; don't rely on this data for safety of life information. I do my best to keep this box up and running, as several hundred rely on it here in Tampa, but as with any volunteer service, I cannot guarantee 100% uptime. Now having said that, last year I only had 30 minutes of downtime total, proving it's VERY stable. The feed, only having a 9600BPS stream of data is -very- low bandwidth usage. The next generation of EMWIN which will be coming will support 38400bps of data. How you use the data is up to you. If you're interested in picking up this feed, drop me an e-mail with your hostname(s), and I'll add you to the allow on my LDM box. The hostname is ldm.aprsfl.net and is running LDM 6.6.5. The name of the feed will be "EXP". If you have any questions, please let me know! Regards, Dave Anderson KG4YZY www.aprsfl.net -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.
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