Coldest Days Of The Year In Wisconsin, Told By Climatologists

MILWAUKEE, WI — Climatologists with the National Oceanic and Atmospheric Administration have unveiled a new interactive map showing the average coldest day of the year across the United States, updated for the latest climate normals through 2020.

The coldest day of the year has already passed for southeast Wisconsin, which is good news after weeks of bone-chilling negative temperature wind chills. However a few factors can make for late-season surprises and the Milwaukee area is no stranger to snowstorms in February or March.

The coldest temps will come to the Midwest in mid- to late January, according to an NOAA post. For parts of northern Wisconsin and the Upper Peninsula of Michigan, the coldest temperatures start Tuesday or later.

Here are a few of the coldest days around Wisconsin (1991-2020 averages):

• Milwaukee
  • Coldest day: Jan. 23
  • Average temperature: 16.4°
• Waukesha
  • Coldest day: Jan. 24
  • Average temperature: 10.5°
• Madison
  • Coldest day: Jan. 24
  • Average temperature: 10.2 °
• La Crosse
  • Coldest day: Jan. 21
  • Average temperature: 7.5°
• Appleton
  • Coldest day: Jan. 27
  • Average temperature: 8.7°
• Green Bay
  • Coldest day: Jan. 26
  • Average temperature: 7.7°

The West usually sees its coldest days in December while the Midwest and East are more likely to experience their coldest days in January or later. Mountain ranges also play a role in creating pockets where some communities see their coldest days later than their neighbors.

NOAA researchers found that Eastern states experienced a more uniform change since 2010, while trends in the West are more of a mixed bag.

"Compared to the 1981-2010 version of this map, there has been a small but noticeable shift of the coldest day to dates 3–6 days later or more at many stations in the U.S. east of the Rocky Mountains," NOAA writes. "This is not surprising given that early winter warming is more pronounced than late winter warming between the new and previous normals periods in this region. While the far northwestern U.S. also shows a shift of the coldest day to a later time, the rest of the western U.S. does not show a consistent pattern, with some stations actually shifting to earlier coldest day times."

View an interactive map charting the coldest days of the year on NOAA's website.

NOAA said its temperature normals can guide long-term planning for economic sectors, helping energy companies predict peak energy demand and construction and tourism industries plot out their seasons. While the 30-year averages help paint a broad picture, there is plenty of room for seasonal deviations and climate patterns like La Niña.

Lucas Combos, Patch staff, contributed to this article.