I should mention, though, that the official climate history contains a trace of snow on earlier dates on a number of occasions in more recent years, presumably due to a passing flurry or a few stray flakes in a rain shower. We also have the 0.1" of snow that was reported on August 25, 1995, although the daily minimum temperature was 44°F - I'm not sure what happened there.
Accumulating snow was observed today at the higher elevations near Fairbanks, such as on Ester Dome (2400') and Cleary Summit on the Steese Highway (2233') - thanks to Brian for pointing out the latter. Here are some webcam shots.
The chilly conditions are a change from what has been a relatively mild month so far (after the cold spell of late August). Soon, of course, the term "relatively mild" will take on a different meaning, as the peak rate of seasonal cooling is only a month away.
Update 10am Sep 13: There's a report of 3" of new snow this morning on Keystone Ridge by 8:45am, with heavy snow continuing. Here's a photo, courtesy of Heather Hrawiec: