Growing and posting from Tacoma WA.
Don't know about the broccoli but the leeks, beets and chard will bounce back and the carrots are toasty warm under the autumn leaves.
We got the same hard freeze/frost. All my cold hard items did just fine. The tree kale/collard was pretty droopy but was perked right back up as soon as the sun came out and the temps got above 32 degrees. Kale is miraculous that way. The items under the grow tunnel were particularly happy and unfazed. Now we are getting heavy downpour rain - so we are going from one winter extreme to another this week. :D
Everything was fine. The ease into colder temperatures was much better than last year. I was thinking to put somethings under a tunnel this year, but didn't.. just never made that time, though what its in should be good until it is eaten. Our rain is pretty torrential this morning as well. The rain barrels will certainly be full now..just in time for more rain :)