I knew the summer-weather was going to rear its ugly little head in our gardens this fall but I hadn't expected it to have an impact this early.
We often see spring bulbs sprouting early with a late fall when the bulb has enough energy stored up (lots this year because of the high sunshine/heat and dry conditions) and is "confused" about whether the dormancy period is over.
There must be some form of "internal clock" as well as an internal hormone switch in response to soil temperature changes creating this issue.
Tulip 'Double Touch'
The problem is that this is earlier than ever. Normally when we see this is late fall and the flower buds seldom develop in time before the cold weather hits and the bulb is forced back into dormancy. Or if they do develop, they manage to (mostly) go through the winter and bloom in the spring.
With this early start in some gardens, all bets are off. You may indeed see buds and flowers this fall if your garden bulbs start throwing leaves.
Here's my best guess (remember it's a guess because we've not seen this before) about what's going to happen with those bulbs.
Narcissus 'Sir Winston Churchill'
Tulips. if they leaf out this year with no flowers - it's a crap shoot. If they didn't flower this spring, they're done and you can dig them out. You won't see flowers next year. Again, if they grow and don't flower now but they did flower this past spring, it's a 50:50 chance - leave them alone and see what happens next year. If they leaf out with flowers - enjoy them, you'll never see flowers on them again. Unless they're short species tulips and those march to their own drummer at the best of times.
Daffodils - if they leaf out now but no flower - no problem. Flowers next year. If they flower this fall, they'll throw leaves next year with no flower. But they'll recover the year after that to produce normally.
As for spring-blooming shrubs that flower in the fall (again not unusual in late fall seasons) they'll live nicely but not flower on those flowering branches next spring. In other words, if a lilac flowers this fall, the flowering branch won't flower again next spring but other non-flowering branches will. You get one flower per growing season - if you get two flowers per growing season, that branch will skip a year.
Absolutely nothing unless you own an ice rink and can put the scrapings over top of the bulb bed to freeze the soil now.
It's the same problem in the spring when they sprout too early - nothing you can do because the bulb has a mind of its own.
Those are the real answers and best guesses to the issue of bulbs starting to develop this fall.