By Drew Lerner

            A large cutoff low pressure center is expected to evolve briefly over the Midwest, Delta and southeastern states for a while late this weekend and early next week. The cold air originates in Canada’s Prairies and not the arctic and the airmass temperatures, although cold, are not cold enough to induce a serious freeze that would harm winter crops or Florida citrus and sugarcane. Considerable cloudiness and frequent bouts of snow will accompany the cold into the Midwest, Tennessee River Basin and interior southeastern states. The cloudiness and precipitation will help hold temperatures up and when the sky finally clears off and the winds turn light most of the coldest air will have already abated from the region resulting in less intensive cold that should not seriously harm the majority of crops.

            The situation needs to be closely monitored because if a better developed surface high pressure center evolves when the coldest air is over the Midwest and southeastern states the temperatures will drop more precipitously resulting in a risk to unprotected winter wheat and to Florida citrus and sugarcane.

There will still be a risk of frost and freezes in Florida during mid- to late-week next week, but some of the data implies readings would not be cold enough for a long enough period of time to induce permanent crop damage. Similarly, the current forecast provides enough snow in the lower Midwest during the coldest days to protect winter wheat that is presently snow free and vulnerable to extreme low temperatures.