Extreme Cold/Wind Chill — Rusk, Wisconsin

2021-02-15 · Rusk, Wisconsin

Event narrative

Several sources of weather sensors provided wind chill values during this prolonged cold snap. The lowest wind chill value of -49F occurred near Ladysmith at 0315 LST.

Wider weather episode

During the first week of February, an Arctic air mass moved southward across the Upper Midwest and continued through the middle of the month. The core of the cold air remained centered across south-central Canada before slowly weakening and moving off to the east after the weekend of February 13th and 14th. Several days of well below normal temperatures combined with subtle wind speeds, generated periods of wind chill values below -30F around Rice Lake and Ladysmith. The bulk of the lowest wind chills, when combined with temperatures dropping to around -20F to -25F, were Sunday morning, February 14th. Due to the terrain, and more sheltering from the higher winds speeds in the valleys, wind chill values of -35F or lower occurred a few hours either side of sunrise. The lowest wind chill occurred at Cumberland airport where a reading of -46 was recorded at 0735 LST.

A secondary surge of low wind chill values occurred late Sunday and into Monday morning February 15th, especially across west-central Wisconsin where wind speeds were slightly higher based on the tighter pressure gradient. Actual temperatures were much lower and winds were lighter. However, even a slight 5 to 8 mph wind speed caused wind chill values to drop below -35F for several hours.

Wind chill values were obtained from ASOS, AWOS, RAWS, and other private weather wind sensors throughout west-central Wisconsin.

The following are some of the lowest wind chill values during the height of the cold snap:

-47F at Cumberland, Wisconsin.

-44F at Woodville, Wisconsin.

-43F at Menomonie, Wisconsin.

Source: NOAA Storm Events Database, event_id 933062. Narrative written by the NWS forecast office that issued the report.