What does "ad" stand for?

[StormRanger67]

I'm a new user of Windy. This is an outstanding resource! Just curious- what does the designation "ad" stand for, relating to weather station observations (i.e. "ad KPWM")? Thanks!

[Korina]

@StormRanger67 Hello, could you please enclose a screenshot of it? Thank you!

[StormRanger67]

[StormRanger67]

@Korina Thanks for your help!

[Gkikas LGPZ]

@StormRanger67
Airport

[StormRanger67]

@Gkikas-LGPZ Thanks very much! That was my guess...

[csabatatar]

@StormRanger67
To be punctual, ad = aerodrome, its a commonly used abbreviated form of it.