wttr.in is translated in NUMBER_OF_LANGUAGES languages:

    SUPPORTED_LANGUAGES

Translated/improved/corrected by:

    * Armenian      Aram Bayadyan @aramix, Mikayel Ghazaryan @mkdotam
    * Azerbaijani   Dmytro Nikitiuk and his Azerbaijani friends
    * Czech:        Juraj Kakody
    * Finnish:      @Maxifi
    * French:       Igor Chubin
    * German:       Igor Chubin
    * Greek:        Panayotis Vryonis
    * Japanese:     @ryunix
    * Macedonian:   Matej Plavevski
    * Romanian:     Gabriel Moruz
    * Russian:      Igor Chubin
    * Slovak:       Juraj Kakody
    * Swedish:      John Eriksson
    * Serbian:      Milan Stevanović @FathVader
    * Swahili:      Joel Mukuthu
    * Turkish:      Atabey Kaygun
    * Ukrainian:    Igor Chubin
    * Welsh:        Daniel Thomas

and many many others.

In the not likely case wttr.in is not yet translated in your language 
you can help with the translation.
Please start with one of the following steps:

    * Open a GitHub issue: github.com/chubin/wttr.in
    * Write an email to igor@chub.in
    * Write PM or tweet to igor_chubin