Back a week ago from my 3rd visit to Alaska. We drive in a loop from Fairbanks down past Denali to Wasilla (near ANC) and back following the pipeline on the Richardson Highway to FAI.
About 1500 miles and very interesting. In September it should be their Autumn AFAIK so leaves would be stunning I imagine.
Last week it was 90º in FAI before we flew out. ^ ^
The previous time there I flew to Barrow and that too was fascinating. Even caught a King Salmon in the Kenai! Here are some notes I made at that time:
http://www.glenstephens.com/alaska.htm
Here is me standing at Point Barrow the most northern point of the USA:
http://home.worldonline.nl/~madejong/ppo/barrow1.jpg
NOTE the heavy snow, and this was summer. Temp was minus something IIRC. September wil be BITTER cold up there I suspect. Enjoy. ^