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Re: Home weather station support

Posted: Mon Jan 02, 2006 6:31 am
by mlewis73
I'd love to have the ability to import my Davis WM II data into Digital Atmosphere along with routine hourly surface obs from legitimate observing stations...

I'm using VWS to import/disseminate my obs to Wunderground and my own homepage.


Mike

Home weather station support

Posted: Wed Jan 04, 2006 12:09 am
by Al Pietrycha
All,

I’ll make a deal with those who want to do what mlewis73 is asking for. If you are a Davis owner and will send your obs to either the CWOP or APRSWXNET, I’ll provide you with an executable that will take your home ob and code the ob to the metar format. You’ll then be able to plot your obs in Dig Atmo. I offer this as a carrot to get more obs in to the CWOP/APRS pipeline so as to obtain a greater number of sfc obs at local NWSFOs. In data sparse regions like the Central and Northern Plains every quality sfc ob received is very helpful to the NWS. PLZ see my previous posts on this issue.

The application to do this was created by Dave Floyd, WCM for the GLD NWSFO and we’ve been using this app for about two years now with great success. The C++.exe runs via a simple batch file. To stratify out potential users, you’ll need 1) a Windows PC, 2) within the Davis software file structure an output file called download.txt - this is what the application parses, 3) you’ll need to set your archiving to 5 minutes, 4) a method to run the script on a scheduler, and 5) you’ll need to know your lat/lon and create an ID so the ob will plot in Dig Atmo.

I hope to have the application and a README file available to download within the next 24 h (can't do this tonight due to the PSU bowl game). I myself am not a Davis owner so I can’t offer support on “How to” questions related to the Davis software, nor do express any guarantees the application will work on your computer. So if you are interested and will send your info to the CWOP or APRSWXNET......

It would be unfair of me to disqualify those that can’t participate in the CWOP so I’ll post to this forum when I have the program online. In the meantime here’s the url to sign up for the CWOP… hint, hint…strong arm approach.
http://www.findu.com/citizenweather/

--Albert Pietrycha

P.S. I think it would be hot if, say, there were 1000 people coding their obs in metar format and all the obs were sent to a central server once every hour. We then could all benefit by ingesting those obs into Dig Atmo. Just a thought.

Re: Home weather station support

Posted: Wed Jan 04, 2006 8:36 am
by packman
Al Pietrycha wrote: P.S. I think it would be hot if, say, there were 1000 people coding their obs in metar format and all the obs were sent to a central server once every hour. We then could all benefit by ingesting those obs into Dig Atmo. Just a thought.
I mailed Tim a few weeks ago making a suggestion about this but I guess he's busy at the moment.

I'm one of the developers of MesoMap Live (http://www.weather-display.com/mmlive.php ) and I already collect data from a variety of sources for use with MML, i.e. Weather Display stations, CWOP data and also some 'amateur METAR' stations.

Two things spring to mind...

1) If people have data in METAR format available, I can already ingest that into my database. If you'd like to provide your data for use in MML then you can already sign up (free) to do that.

2) I don't currently output data in any format other than for MML, but it probably wouldn't be difficult to output data into a METAR format file to be used up by DAWS.

There is a one problem I can see...how to identify the additional METAR stations. MML uses it's own coding system (using a 7 character string), but a METAR report should really have 4 character codes. I don't know if DAWS will handle longer codes, but if we have to use 4 character codes that might be tricky.

Posted: Wed Jan 04, 2006 9:39 am
by packman
I've just been experimenting with station names in DAWS. It appears that without changes to DAWS a station can only be referenced by either a 4-char ICAO code or 5 digit WMO code.

I assume that the DAWS METAR ingestion code uses ICAO codes, so any extra stations will need to be given 4-character codes. If anyone can confirm this it would be useful, but I think all current ICAO codes begin with an alphabetic character? This means that additional stations could be given codes beginning with numbers, e.g. 0ABC, or even all digits, e.g. 0123.

Posted: Wed Jan 04, 2006 11:49 am
by carseman
Chris,
Have you looked at the digatmos.stn file in your DAWS main directory. It appears to me that there would be the possibility of adding in the WDxxxx format stations somewhere. Hopefully someone here could comment.

Chris

Posted: Wed Jan 04, 2006 12:05 pm
by packman
I've added a couple of test stations to my digatmos.stn file to see what might work. The file appears to needs at least one of ICAO or WMO (otherwise there's nothing to identify the station).

I've added a test station using a dummy ICAO code (ZZZZ) and that worked OK. A longer ICAO code, e.g. WD00001, was truncated as 'WD00' on display, but the METAR ingester does match up the longer name in the METAR data file with the long ICAO code in digatmos.stn.

I think that based on this we'd need to use 4 character ICAO codes beginning with a number. I'd also have to invent (yet another!) coding for the stations in my database.

Posted: Wed Jan 04, 2006 12:20 pm
by packman
Another thing to consider is how much info would be needed in a METAR? Temp, pressure, humidity/dew point, wind speed/direction are fairly easy, but some CWOP data doesn't even have all that. Is there a minimum set of data below which it wouldn't be worth generating any METAR output for the station?

Posted: Thu Jan 05, 2006 3:34 am
by Al Pietrycha
Okay,

The file you need is located at: http://www.dlfloyd.com/misc/metar.zip
This zip file contains the program and the readme file. The readme is in Word format. Dave took a chunk of his time to write the readme in a style that we hope will work for the majority of users.

Perhaps someone can take the code and modifiy this for any of the various home wx stations that have data loggers.

We hope this helps... keep us posted.

Have I mention to you about the Citizens Weather Observer Program?

:-)

--Al

Posted: Mon Jun 12, 2006 5:37 pm
by Mark
I've written a Java app that reads data from a Hyundai WS-05 (Re badged Lacrosse WS320) I'm struggling with the history file which is a ring buffer, but should be done any time soon.