It is too late if anything. You can plant arugula and turnips, they will come up even now if you water them.

They are so-called "fall" crops because that is when they are intended to mature, not that they are sowed in fall. Fall brassicas, for instance, in the middle latitudes are sown in July.

I agree. You missed you chance for many things already. You may still have time to transplant kale and lettuce starts as well as direct seed fast growing, cold hardy things like what Glib mentioned as well as radish and other greens in the mustard family (tatsoi, mizuna, boc choi, etc).
-Mark