Norway High School softball coach Robert “Kuba” Bal clears snow off the field in preparation for the spring softball season. The first NHS varsity softball game is scheduled for April 13. (Iron Mountain Daily News photo by Terri Castelaz)

IRON MOUNTAIN — February’s cold snap — which included 13 straight days of lows dipping below zero — likely won’t be repeated as spring approaches.

The polar vortex is strong once again, which means Arctic air is less apt to plunge deep into North America, forecasters say.

“A milder-than-average March is expected over much of the eastern two-thirds of the nation, while a chillier-than-usual March is forecast only for parts of the Northwest and northern Rockies,” said Todd Crawford, chief meteorologist with The Weather Company.

This week, temperatures are expected to soar into the 50s locally, with a large storm system bringing rain Wednesday. There is a risk of severe weather in Illinois, with a chance of gusty thunderstorms and isolated tornadoes, forecasters say. A cold front is then expected to push temperatures back again.

A long-range outlook from the National Weather Service calls for 38% chance of above-average temperatures from now through the end of May, and a 29% chance of below-average.

La Nina conditions — a cooling of the central Pacific Ocean that affects weather patterns around the globe — are likely to persist through early spring.

“The general pattern in March could resemble what is seen in a typical La Nina — namely, colder in the Northwest and generally warmer elsewhere in the U.S.,” Crawford said.

A warming above the North Pole early this year stretched and displaced the polar vortex, allowing colder air to invade the U.S. At Iron Mountain-Kingsford, temperatures dipped below zero on 16 of the 28 days in February, including 13 straight from Feb. 5 through Feb. 17. The coldest was minus 27 on Feb. 14, a new Valentine’s Day record.

Temperatures did, however, manage to climb above zero every day in February. A reading of 3 degrees on Feb. 7 marked the coldest daytime high. The highest reading was 52 degrees on Feb. 28.

Snowfall in February measured 15.5 inches, according to observations at the Iron Mountain-Kingsford Wastewater Treatment Plant. That was about 4 inches above average and brought the total for the season to 33 inches, which includes 6 inches of snow that quickly melted in October. Water-equivalent precipitation was 1.04 inches, about average for the month.

Snow depth at the end of February was 10 inches, which compares with 18 inches a year ago and 31 inches at the end of February 2019. The snow total this winter is roughly half the normal amount.

Spring will officially begin at the vernal equinox, which will occur at 4:37 a.m. Central time on March 20.

Low ice coverage on the Great Lakes could have implications for the region’s weather in the months ahead, according to AccuWeather meteorologist Paul Pastelok. Despite plunging temperatures in February, ice coverage remained significantly lower than normal at 16.2% across the Great Lakes on March 1.

Since water is not particularly cold in the lakes, air temperatures across the Midwest could go through a significant rise at the end of spring, leading to an unusually warm May, Pastelok said.

Chances are good for heavier precipitation as well. The NWS estimates a 50% chance of above-normal precipitation in the U.P. from March through May and just a 17% chance of below-normal.

“We do think it’s gonna get pretty wet later in March and April,” Pastelok said of the Midwest in general.

The U.S. Drought Monitor currently shows abnormally dry conditions across the U.P. and northern Wisconsin.

Jim Anderson can be reached at janderson@ironmountaindailynews.com.