Well...I instructed for a year in Florida, and generally weather wont stop you. Sometimes the tunderstorms can stop you for part of the day, but its nothing like here in Northen Europa.
I actually had a student from England(London) and she flew intensily for 3-4 weeks (she had past expirience) and got her PPL.
I have some of the same expiriences as you do with Norway.
Terrible weather that grounds me for weeks at a time (westcoast)
and it took waaaay too long to get my PPL.
In the time it took to get my Norwegian PPL, I got my COMM ME&SE IR+all the instructor ratings.