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Latitude Longitude discrepancy with NOAA

Posted: Thu 22 Apr 2021 8:43 pm
by boss281
Seems to be my week for weather station issues.

My Cumulus MX installation pushes WU, CWOP, Windy (which I think may be redundant due to CWOP) and PWS Weather. On all sites the time stamp for a row of data is correct.

I recently discovered that NOAA consumes CWOP data and presents your CWOP station here (I'm FW2392): https://www.wrh.noaa.gov/mesowest/getob ... 392&num=48 . Note the city and state are correct, but the longitude "77.05917" is incorrect. It's missing a (-) negative sign. So the time stamps are for the XJT time zone. NOAA says they are "removed from the data" and to check with CWOP, CWOP says the longitude needs corrected in CumulusMX. Yet, the CWOP data is correct. Here is my setup in CumulusMX:
Screenshot 2021-04-22 052241.png
I live in Maryland USA as a reference.

So, wherein lies the problem? Stumped.

Re: Latitude Longitude discrepancy with NOAA

Posted: Fri 23 Apr 2021 8:12 am
by mcrossley
Cumulus sends the longitude to APRS as a string in the format "dddmm.ss[E|W]" so it does not use a positive/negative number. APRS/CWOP must be doing the conversion.

Re: Latitude Longitude discrepancy with NOAA

Posted: Fri 23 Apr 2021 8:32 am
by mcrossley
Looking at the APRS data everything is correct.
Position: http://www.findu.com/cgi-bin/find.cgi?call=FW2392

And the raw data shows longitude is correctly being uploaded as West: http://www.findu.com/cgi-bin/raw.cgi?call=FW2392

So the issue is definitely between CWOP and NOAA.

Re: Latitude Longitude discrepancy with NOAA

Posted: Fri 23 Apr 2021 2:24 pm
by boss281
mcrossley wrote: Fri 23 Apr 2021 8:32 am Looking at the APRS data everything is correct.
Position: http://www.findu.com/cgi-bin/find.cgi?call=FW2392

And the raw data shows longitude is correctly being uploaded as West: http://www.findu.com/cgi-bin/raw.cgi?call=FW2392

So the issue is definitely between CWOP and NOAA.
I figured as much but I'll have to push back as I'm getting the finger pointed at me right now...
Thanks for verifying.

Re: Latitude Longitude discrepancy with NOAA

Posted: Fri 23 Apr 2021 9:23 pm
by beteljuice
However ...

The problem does seem funny peculiar to you ?

I checked a couple of your APRS neighbours both with NOAA and findu.
According to APRS your location format is identical and correct, but NOAA gives them EDT whilst you are in China :lol: