As severe weather season arrives in Minnesota, a powerful low-pressure system is set to move across the state on Tuesday, presenting a once-in-a-decade strength storm. According to climatology data from the Twin Cities National Weather Service office, this system has the potential to generate multiple rounds of thunderstorms capable of producing severe weather.

The system is expected to ignite the first wave of potentially severe storms on Monday evening in southern Minnesota. The National Oceanic and Atmospheric Administration's Storm Prediction Center has classified this initial risk as marginal (Category 1 of 5) around the Twin Cities. However, the risk intensifies to slight (Category 2 of 5) south of the Twin Cities, making severe storms more likely in that area.

The High-Resolution Rapid Refresh model provided by NOAA shows scattered thunderstorms developing around 7 p.m. on Monday in southwestern Minnesota. These storms may reach the Twin Cities between 10 p.m. and 11 p.m. The strongest storms are anticipated to occur across southern Minnesota, especially along the Interstate 90 corridor towns of Albert Lea, Austin, and Rochester.

Tuesday is expected to bring a more widespread severe weather risk to the Twin Cities and southern Minnesota. The slight risk category extends farther north, encompassing Mankato, the greater Twin Cities area, and northeast towards Rice Lake, Wisconsin. A higher enhanced risk is in place for most of southern Minnesota. While the highest severe risk remains south of the Twin Cities, any storms within the risk area on Tuesday have the potential to produce damaging winds, hail, and even tornadoes.

NOAA's NAM 3 km model projects two primary storm waves on Tuesday. The first wave will move through southern Minnesota towards the Twin Cities area in the morning, while the second and likely stronger wave will develop across southern Minnesota in the afternoon and move into the Twin Cities late in the afternoon or evening. All forms of severe weather, including damaging winds, hail, and tornadoes, are possible with these storms.

In addition to the severe weather, heavy rainfall is also expected across much of Minnesota. Forecast models indicate a swath of 2 to over 4 inches of rainfall, primarily in western and central Minnesota. The Twin Cities and southern Minnesota are likely to see 1 to 2 inches of rainfall, with some localized areas possibly receiving up to 3 inches.

Residents are advised to stay alert and closely monitor severe weather watches and warnings on Monday night and throughout Tuesday, particularly in the southern regions of Minnesota.