A friend and I were thinking about trying Shasta this fall (like late sept-oct), but I'm worried there may not be that much snow. Am I right, or is there a possibility that there will be some left since its been a bumper year in terms of snow?

Clear Creek Route (east side of the mountain) is a good route for that time. There probably won't be any snow at that time or not much anyways. It's the least Alpine Experience route on the mountain. It's 3 miles from the trail head to Clear Creek Springs. Clear Creek Springs is the only water source on this route and where most people base camp. From here you climb up a broad back ridge around 20 degrees (lots of scree) until you get to the crux of the climb at around 13,000 ft. Here is where you cross the top of the Wintun Glacier. Depending on when you go, will determine if you will cross snow or not. It's always recommend to still have ice-axe, crampons and helmet even when there's no snow for the just in case (getting off route). Here's a bit of trivia for that route. It's the route that the first mules went up in 1883. Dynamite and Cropper. In 1903, the first horse "Old Jump Up" made it to the top. Unfortunately, he died the next day of over exhaustion. Poor horse.
For more information, stop by the Mt. Shasta Ranger Station. They have an excellent powerpoint of this route and all main routes on Mt. Shasta.
Cheers and Happy Climbing!
http://www.mountshastaguide.com

Thanks for the suggestion! We may scrap the idea if it's going to mostly be scree scrambling. When will there be significant snowpack again? Probably have to wait until spring?

Clear Creek is a popular destination but not my first recommendation in the late summer/fall. I think it's popularity lies in the relative lack of technical difficulty. It's a great climb (and better ski descent!) in May and early June, but as far as a climbing route, most will find the rock and scree tedious late in the season.

The glaciers on Mt. Shasta can be in prime condition in September and later in a good snow year like this. The Hotlum Glacier will be fabulous for a snow and ice climb with big cracks and ice falls to explore. The less technical south and west side routes will be mostly rock and scree, but the glaciers should be in great shape, maybe more ice and old snow, but still spectacular. Weather can be a factor with short days and the possibility of early snow storms. The Hotlum/Bolam ridge can be pretty decent as well, but may get pretty icy in some exposed areas at that time, although it's easier to avoid the crevasses on this route.

Don't rule out a fall climb yet, with the way the snowfall has been this season, it could be awesome!

An Underhill from Berkeley, any relation to the climbing pioneer?

Hmm, very interesting. Exploring the glaciers sounds fun! We'll definitely consider that when we make our decisions, thank you!

I wish I were related to that Underhill, but when I made the account, I chose it as a nod to Tolkein (all the travel songs, etc, in his books are great and make me all wanderlusty).

You never know how much snow may remain over the summer. Sometimes, and I expect it this year as well, there is still enough snow spots left aside on the standard route to enjoy the climb. Otherwise the North Gate approach would guarantee more snow due to glaciers. However, it may be partially or even completely icy that late in the season, but at least before you get to that point you may enjoy a very beautiful trail

When the time comes, check the conditions again.