We are opening up the briefing that we sent to our corporate clients on the morning of Thursday, March 30, 2023, to the public on the complex, messy Spring Storm that’ll bring blizzard conditions and severe weather to the central United States. We hope that everyone in the path stays safe. We will also continue to have updates on our Weather Videos page.

Complex Spring Storm Brings Severe, Blizzard, Snow, And Ice Concerns Through Friday

Praedictix Briefing: Thursday, March 30th, 2023

Key Points:

• A system pushing into the central U.S. today and Friday will be the focus for a multitude of impactful weather to end the week.
• Heavy snow and ice will impact the upper Midwest in two rounds – one today into tonight, with the second Friday into Friday Night. Icing of up to a quarter inch will be possible from the western Dakotas across central Minnesota to northern Wisconsin – this will fall mainly through Friday morning. Combined snowfall of 6-12″ will also be possible from central South Dakota across central/southern Minnesota to the U.P. of Michigan.
• Strong wind gusts to 50 mph tomorrow will cause whiteout/blizzard conditions where the snow is falling
• A bi-modal severe weather outbreak is expected in the Mississippi Valley on Friday, with strong and long-tracked tornadoes as well as destructive wind gusts the primary threats. The threats are maximized in eastern Iowa/western Illinois and in the Mid-South around Memphis.

Wintry Precipitation Starts Today, Continues Friday – Severe Threat Friday. A couple of rounds of wintry weather are expected to impact the Upper Midwest as we head through the end of the week.

• The first round – today into tonight – will bring snow across mainly North Dakota into northern Minnesota and the U.P. of Michigan. However, this round will bring a band of at least 0.1″ to 0.2″ of freezing rain across parts of western and central Minnesota later today and through the overnight hours, leading to slick conditions.
• The second round – Friday into Friday Night – gets going by the midday hours tomorrow. Rain will change over to snow from northwest to southeast during the afternoon and evening hours, with a potential mixed precipitation or icing period in between that changeover. In the Twin Cities metro, this changeover is likely to occur around or a little after sunset. This round will also feature wind gusts to 50 mph, which could cause whiteout conditions with the falling snow.
• The second round is what will also spark off severe weather across Iowa into Illinois Friday afternoon into the overnight hours, with tornadoes and damaging winds possible.

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Winter Weather Alerts. Due to the expectation of snow and icing later today into tonight, Winter Weather Advisories have been issued. Winter Storm Watches are in place Friday and Friday Night for heavy snow and blizzard conditions. Winter Storm Warnings in northeastern Wisconsin are in place for snow and freezing rain tonight into Friday.

Snow Forecast. Over the next couple of days a heavy, wet snow will fall across portions of the upper Midwest. Some areas may only see snow from one of the two parts of this storm, while others will see snow in both parts. Areas of 6-12″ can be expected – especially in parts of the Dakotas into western Minnesota, and from eastern Minnesota into the U.P. of Michigan. Some areas could see over a foot fall. For the Twin Cities metro, most of this (minus a few tenths of an inch) is expected to fall Friday Night. In areas like Duluth, they’ll see snow from both rounds of precipitation.

Probability Of 1″ Per Hour Rates From 1 PM Friday To 7 PM Friday.

1″+ Hourly Snowfall Rates. With the band of heavy snow that forms Friday afternoon into the overnight hours, hourly rates of 1″ per hour will be possible across the Upper Midwest. That means snow will be hard to keep up with if you’re trying to keep surfaces snow-free, and blowing snow concerns on top of the 1″+ per hour rates will make any project like that even more difficult to accomplish.

Accumulating Ice. In the battleground between “warm enough for rain” and “cold enough for snow” across parts of the eastern Dakotas through central Minnesota into northern Wisconsin, a band of at least 0.1″ to 0.2″ of ice (with possibly isolated higher amounts) will occur. This is most likely to occur later today into early Friday – with icing appearing to be less of a concern across the region with the second round Friday afternoon/night.

Blizzard Potential Friday. Especially in parts of the Dakotas into Minnesota, blizzard conditions will be possible Friday into Friday Night due to wind gusts in the 40-50 mph range (with isolated higher gusts). This will cause greatly reduced visibility with the falling snow across the region – especially in periods where the snowfall rate is up toward 1″ per hour. This will also cause the potential for some drifting.

Northern Severe Threat Friday. Meanwhile, in the warmer sector of the storm, we will be watching the potential for a severe weather outbreak. We’ll start off with the northern part of the threat area first, where there is a MODERATE risk of severe weather (threat level 4 of 5) already in place across portions of eastern Iowa, northwestern Illinois, and extreme northeastern Missouri. This includes Dubuque, Cedar Rapids, and Iowa City (IA), the Quad Cities metro, as well as Galesburg (IL). An Enhanced Risk surrounds it from the Minnesota/Iowa border and southwestern Wisconsin southward, including Des Moines and St. Louis in the northern part of the nation.

Strong Tornadoes, Destructive Winds, and Very Large Hail. Storms are expected to form in Iowa in the early afternoon hours, quickly racing eastward toward the Ohio Valley by the overnight period. Storms will start off individually, with strong tornadoes (EF2+ strength), destructive wind gusts (75+ mph), and potentially very large hail (2″+ in diameter). These storms will become a line as we head later in the day as they charge eastward. At that point, damaging winds become the primary threat, followed by embedded tornadoes within the line.