WEST MICHIGAN — For the first time this winter, it’s possible we will drop below zero just in time for Valentine’s Day morning. I am forecasting a low of -1°F for Grand Rapids, which would be the coldest night we’ve experienced since February 28th of last year when the mercury dropped to -4°F. (We nearly dropped below zero on March 5th last year with a low of 0°F right on the button.)
Early this morning, the official low at Grand Rapids airport was 3°F. With even lighter winds and the possibility of more clearing, it is likely that we will get even colder by tomorrow morning. The reason for the clear, calm, and cold conditions: A big area of Canadian high pressure crossing the south end of lake Michigan:
Upstream from us in Minnesota and Iowa, lows dipped below zero in many locations early this morning as that high made its presence known. Minneapolis/St. Paul dropped to -6° for example, and it was -4° for a low in Mason City, IA. Although these airmasses often modify somewhat as they cross Lake Michigan, I still think we’ll drop to near or somewhat below zero in inland locations due to the light winds. Closer to the lakeshore itself, lows will most likely stay in positive territory.
Although this shot of cold air is a big deal because it’s been such a mild winter so far, it’s far from record territory. The record low for Valentine’s Day morning is -24° set back in 1899.
After bottoming out tomorrow morning, temperatures will get milder as a whole throughout the coming workweek. That cold high pressure system will slide to our east, allowing a mild return flow from the south to develop tomorrow night into Monday. By Friday, in fact, high temperatures should be well into the 40s.