January 15-21, 2025

Temperatures

This week was characterized by some of the coldest air of the winter thanks to several cold fronts on either end of the week. Temperatures averaged below normal across the region by 4-8°F (Figure 1). An area along the Ohio River in Illinois, Indiana, Kentucky, and Ohio was around 10°F below normal for the week.

Minimum temperatures were very cold, and generally below zero for several days in spots. Much of the region averaged 6-10°F below normal, with some spots seeing minimum temperatures average over 10°F below normal for the week (Figure 2). In Gunflint Lake, Minnesota, a station recorded a temperature at or below -39°F for two consecutive days, January 20-21, for only the 8th time in January since records began in 1894. In Murray, Kentucky, the minimum temperature was below 5°F for two consecutive days, January 20-21, making it the coldest stretch in January since 2018.

Maximum temperatures were also anomalously cold, with most of the region anywhere from 4-8°F below normal (Figure 3). In fact, most of the daily records this week were the result of record low maximum temperatures, not record low minimums, with over 130 record low maximums this week (Figure 4). In Gunflint Lake, maximum temperatures stayed at or below -13°F for two consecutive days, January 20-21, which has only happened 3 other occasions in January since 1894, twice in 2014 and once in 1995. At Pokegama Dam, a COOP station in northern Minnesota, the temperature only reached -16°F on January 21 and has only happened 3 other instances in January since 2000.

Precipitation/Drought

With a dominating high pressure and cold, dry air for much of the week, there was little precipitation. Most areas along and west of the Mississippi River did not receive any precipitation. Eastern parts of the region—Michigan, Indiana, Kentucky, and Ohio—received the most precipitation, which was, at best, 50-75 percent of normal (Figure 5). There was some moderate rainfall due to a warm front lifting over the area around January 17, but it quickly changed to frozen precipitation as colder air reentered the area. Lake effect snow was responsible for the highest totals this week, with nearly a foot of snow along Michigan’s snowbelts (Figure 6). Some bands of lake effect snow caused whiteout conditions for travel along the Mackinac Bridge.

There were nearly no changes in the drought monitor this week, save a slight improvement in abnormally dry conditions along the Illinois/Indiana state line (Figure 7).