Best time to travel to Alaska

Many touristic things were closing down, or thinking about closing down, around the start of September last year at the tail end of my Alaska trip. Steward and Prince George might be nigh to ghost towns in your itinerary. Fairbanks wouldn't be so much (though e.g. the Pioneer Park attractions would be closing around that time) since it's very much a year-round city, not as completely dependent on tourism for its continued existence. Gas and services along the way would likely also be less available, but should still be entirely adequate. Weather certainly could be a consideration towards the end of the timeframe, too, as was mentioned.

I think it would be preferable to shift your schedule a few weeks back if practical, but if not I'm sure it would be a delightful trip none the less.