Wednesday is the 62nd anniversary of the coldest day ever in Madison — Jan. 30, 1951 — when the temperature dropped to minus 37 F.
As we described in a column a couple of years ago, to get the air that desperately cold in Madison a healthy snow cover is necessary. This January, we had a warm spell near mid-month that effectively melted most of the snow remaining from our December snowstorm. Thus, even though last week’s cold was the worst of the season thus far, it was a lot less cold than it might have been had it occurred while we had a deep, fresh snow cover.
Looking ahead for the rest of the season, we are nearing winter’s coldest point, climatologically (approximately Feb. 1), and until or unless there is fresh snow on the ground we are likely to escape the kind of cold that keeps the temperature below zero throughout the day. In fact, in the last five years there have been only two days on which the daily high temperature has been below zero — Jan. 15, 2009, and Jan. 19, 2008 — both with a high of minus 2 F in Madison.
In a related item of local interest pertaining to the severity of the winter thus far, state climatologist Dr. John Young officially declared two weeks ago that Lake Mendota froze over on Jan. 14, the third-latest date in an unbroken 159 years of observation.
This late date was a combination of the very warm summer and relatively warm autumn that allowed anomalous amounts of heat to be stored in the lake as winter approached. Then, given the lack of truly cold air in our area until recently, it has taken longer for the lake to give up its excess heat. These factors led to the very late freezing date this year.