OTTUMWA — Temperatures are expected to warm a bit starting Wednesday, but it’s not time to trade coats for shorts quite yet.
A wind chill from the National Weather Service for most of Iowa expired Tuesday morning. Wind chills will remain frigid until Wednesday morning, when a slow rise is expected to send wind chills back into the positive single digits.
The forecast high on Wednesday is 18 degrees, according to a National Weather Service forecast. The wind chill would top out at about 9 degrees.
Temperatures will dip back below zero briefly overnight Thursday and Friday. But by the weekend, forecasters believe temperatures will climb above freezing for the first time since Feb. 4. The high on Sunday is forecast for a balmy 37 degrees, though there’s a slight chance of snow. On Monday, forecasters say temperatures could reach 39 degrees.
The arctic blast has frozen southern Iowa for nearly two weeks already, with winds creating dangerous wind chills of minus 30 degrees and lower.
Conditions have caused school districts to cancel and delay school days; some have switched to virtual learning.
In Ottumwa, the wind chill dropped to minus 32 degrees early Monday morning, and to minus 30 degrees early Tuesday.
Frostbite can occur within 30 minutes for wind chills below minus 17 degrees. As wind chills near minus 35 degrees, frostbite can occur in as little as 10 minutes.
Wind chill is the apparent temperature caused by airflow. Air temperature is how hot or cold the air is. The term wind chill is used when the apparent temperature is lower than the air temperature, and heat index is used when the apparent temperature is greater.
According to weather service records, three days broke air temperature records in Ottumwa: Feb. 7 (minus 11 degrees), Feb. 13 (minus 7 degrees) and Feb. 15 (minus 10 degrees).
The unseasonable weather wasn’t just in Iowa. Effects of the arctic blast stretched far and wide, all the way down to the Mexico/United States border.
A winter storm in the southern United States left millions without power, some due to the storm and others due to intentional blackouts meant to conserve power.
MidAmerican Energy asked its customers Monday to conserve their natural gas use, citing a potential supply issue. The company said the flow of natural gas to Iowa was impacted due to frozen wells in the southern United States. In an update Tuesday, they said their gas supply was currently meeting customer demands.
Alliant Energy said it currently had sufficient supply to meet customer demands, but still offered tips for customers to stay warm and safe while reducing their energy usage.
Southern Iowa Electric Cooperative, which serves areas of Wapello, Davis, Van Buren and Appanoose counties, said its power provider has said intentional rolling blackouts may be necessary.
A Facebook post by the cooperative said, “We are encouraging members to continue to minimize and prioritize electric use to help the situation. Blackouts are expected to last an hour or less and repeat. If blackouts are necessary, it is unlikely that adequate notification will be possible.”