I doubt it. Squash of almost any kind wants hot weather. I'd be looking into crops like Swiss Chard, lettuce, peas, cabbage beets and maybe even carrots.

George
Tahlequah, OK

Overall, I guess I have to agree with George. Shorter days and cooler temps, even if there is no frost, aren't going to be good for it.

The only thing I wondered about, though, is what kind of weather you will actually have in your region during the fall. I know that in some parts of California, some of the hottest weather of the year comes in fall with the Santa Ana winds. If you plant it now, I would try to stick with varieties with the shortest days to maturity. I guess you wouldn't be out much but a little seed and a little space. I would be very vigilant about fungal diseases and plan to spray regularly if I were you, and also use heat-retaining methods like black plastic over the soil and perhaps some sort of plastic tent later on when it gets cool.

I think I will pass on the acorn squash for my fall garden, I'm going to be planting alot of other stuff anyway, thanks for your input, this forum rocks :)

I doubt it will be successful.

But phone your county's University of CA Extension Service office. They'll know for certain.