Where do callsigns come from?

[KU4GO]

Hi All!

I'm new to the weather world.  I have a question (only one for this go round, ha-ha!) I can't seem to find an answer to, hopefully this is the the correct forum.  I've been able to obtain a Davis Vantage Pro2 station that I'll be using with my Mac Pro computer to create a PWS (Personal Weather Station).  In looking at other stations, I see their PWS have a wide variety of callsigns.  I realize as an amateur radio operator I'm able to use my own callsign, but where do these other callsigns come from?  I see KNC, MDO, KSC and many others.

Just curious... thanks in advance!
Alan - KU4GO

[SLOweather]

A lot of them are issued by Weather Underground when the station signs up to upload data. The WU callsigns take the general form of

K (2 letter state code) (5 letter city code) (number)

For instance, my San Luis Obispo, CA WU call is:

KCASANLU1, where:

K CAlifornia SANLUisobispo 1 (first station to register from here) 

[KU4GO]

Thanks for the quick reply...  Yes, I see what you mean.  I see also alot of the M*.* are part of MADIS which I was unfamiliar with.  I thought maybe, like an amateur radio callsign, they were somehow assigned by some single governing body, and I couldn't detect a pattern.  But your answer clears it up.  Thanks!

"K CAlifornia SANLUisobispo 1 (first station to register from here)"

Very nice! Congrats on being the first!

- Alan

[weatherforyou]

A lot of them are issued by Weather Underground when the station signs up to upload data.

... or PWSweather.com.