It got up to 40 today and I thought the sap would flow well. That was not the case. I have 2 lines that are bring sap from a sunnier section of woods, they flowed well, all of the others that are back deeper in the woods where there are a few hemlocks (evergreens that shade the tubing a lot) never got warm enough to flow. Maybe tomorrow.
Tonight it will freeze again and tomorrow is forecast to get to 43F, then get to 43 again Tuesday. That it seems should turn the trees on. In fact the next several days should be good sap days. Time will tell.