I've run records for the last 5 years and every year I have gotten my sheep on pasture about the second week of April. It has been the same way in busting sod for the corn; I have never seen a year where we did not drop the plow before my birthday, May 8th, and while some years appeared that we would, inevitably something happened weather wise and we were delayed until just after my birthday, and this goes back 38 years! That is the beauty of running records, you get a trend going and from that you can make plans for the future. From example, since October the calculations showed that I would run out of hay on March 7th based on hay waste, number of head, dry matter per day, etc, and by all accounts that is when I will run out. We had a good hay year though so there is plenty of it to be had from others, so I am in good shape there. I can buy a month's worth of hay and still be in the green (in more ways then one!)
I know someone on here said that you better have half your hay and wood pile left come Ground Hogs Day, but my Grandfather always said that for New Years Day. I tend to think the latter is right because February is a short month and the days get longer and the sun is higher up in the sky. I know I do not burn nearly as much wood/coal or propane from Feb 2nd to April 15th then I do from October 15th to February 2nd. That is a 38 day difference; and for some, firing up on October 15th is a late start. Either way, I might be low on hay, but I am predicted to run out of firewood on April 15th 2017. I do not need computer modeling to tell me that though; a big pile of firewood is prediction enough!