I was reading the SeekersGuidance answers archives today, and found these useful answers about travel. Good pages to bookmark if you’re travelling this summer!
1) Basic Rulings of Travel
Important points: for stays longer than 15 days, legally a resident, and should not be shortening prayers. For stays shorter than 15 days, “when one is a traveler, it is mandatory (wajib) to shorten the obligatory four-rakat prayers (zuhr, asr and isha) to two rakats. One still prays the sunna prayers though, unless in the midst of a journey and in the rush of travel.”