Not here in Australia. :-) Join us on the beach!
Fellow Aussie here; was going to say the same thing
Hello, I am from Bavaria and I like skiing!
Why "téli" and not "tél"? Why is the "i" added?
It's to change it from the root word, which is a noun, into an adjective. You'll see this pattern with all the seasons (tavaszi, nyári, őszi, téli), although I'm still too much of a beginner to know if this applies to other nouns
Yes, this is a common and productive formative suffix, although not the only one when it comes to relational adjectives.