Severe Weather Threat for Iowa: Strong Tornadoes, Large Hail, and Damaging Winds Possible

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A significant severe weather event is expected to impact Iowa later today into tonight. The Storm Prediction Center has placed northern Iowa under a Moderate Risk (Level 4 of 5) for severe thunderstorms, highlighting the potential for strong to intense tornadoes, very large hail, and damaging wind gusts. This threat will primarily target northern Iowa, but some risk extends into central Iowa as well, especially if isolated storms can form farther south.

This setup is driven by a powerful storm system currently moving across the central United States. A strong surface low over South Dakota is pulling warm, moist air northward into Iowa. As the low tracks northeast into Minnesota by this evening, a warm front will lift north across the state, bringing increasing instability (fuel for thunderstorms) and very favorable wind profiles for rotating storms, known as supercells. Dew points are already rising into the 60s, and very strong winds aloft (a jet streak of 70-80 knots at 500mb) are setting the stage for explosive storm development.

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Iowa Day 1 Tornado Risk: Yellow and red hatched areas represent a significant tornado threat.

Storms are expected to develop by late afternoon, roughly between 1–3 PM, first near the South Dakota/Minnesota/Iowa border. These storms will quickly move east and southeast across northern Iowa during the late afternoon and evening. The environment south of the warm front — which includes much of northern Iowa — will support the development of discrete supercells, the type of thunderstorms most capable of producing strong tornadoes and very large hail (golf ball size or larger). Wind shear will be strong enough that any storm able to stay isolated could rotate and become tornadic.

There is a chance that storms will eventually cluster into a line later tonight. If this happens, the risk for damaging straight-line winds will increase, but embedded tornadoes would still be possible within that line. Any discrete storms ahead of the main line this evening would have the greatest chance for strong or long-track tornadoes.

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Farther south into central Iowa, the severe weather threat is a little more uncertain. While the atmosphere will be very unstable and supportive of severe storms, a cap — a layer of warmer air aloft that suppresses thunderstorm development — might prevent storms from forming unless strong forcing can break through it. If storms do manage to form in central Iowa, they could also become intense very quickly, producing large hail, damaging winds, and possibly tornadoes.

Residents across northern and central Iowa should closely monitor the weather today, have multiple ways to receive warnings, and be prepared to act quickly if a Tornado Warning is issued. Conditions favor rapidly developing and dangerous storms, particularly between late afternoon and midnight. Stay weather-aware, review your safety plans now, and be ready to seek shelter if needed.

Significant Severe Weather Threat for Iowa on Monday: Tornado Outbreak Possible

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A serious severe weather event is expected to unfold across Iowa on Monday, with a moderate risk for severe thunderstorms focused over central Iowa and extending into southeast Minnesota and western Wisconsin. An outbreak of severe storms appears likely, with the primary threats being large hail, damaging wind gusts, and the potential for strong to intense tornadoes, some of which could be long-tracked.

The atmospheric setup is highly concerning. A strong upper-level jet stream will sweep northeastward across the region, while a deepening surface low moves from the northern Plains toward the Great Lakes. In response, warm and humid air will surge northward across Iowa. With broken to scattered cloud cover allowing sunshine to heat the surface, the atmosphere will destabilize rapidly. This will create a volatile environment capable of supporting explosive thunderstorm development.

Storms may begin forming as early as midday across western Iowa and western Minnesota. These initial storms are likely to be supercells, capable of producing very large hail and tornadoes. As the afternoon progresses, storms farther south and east across Iowa are expected to remain more isolated — a setup particularly favorable for strong tornadoes. Supercells that develop within the open warm sector will tap into extreme levels of atmospheric instability and very strong wind shear, increasing the risk for long-lived, intense tornadoes.

By late evening, a powerful cold front will sweep through, likely organizing storms into a squall line. Even as the storms transition to a more linear mode, the threat for damaging winds and embedded tornadoes will persist into the overnight hours.

Iowa sits in the heart of this threat area, where conditions will be most supportive of significant severe weather. Surface heating will be strong enough to erode any lingering cap, allowing storms to form freely. Wind shear values are forecast to exceed 60 knots — a critical ingredient for organized, rotating supercells and tornado production. The combination of strong instability and intense wind shear makes this a particularly dangerous setup.

Residents across Iowa should take this situation seriously. It is important to have multiple reliable ways to receive weather warnings, including NOAA weather radio, weather apps with alert notifications enabled, and access to local news. Make sure your tornado safety plan is in place and that you know where your safest shelter is, ideally in a basement or a small, windowless room on the lowest floor of your home. Charge your devices in advance and remain alert throughout the day, especially during the afternoon and evening hours when conditions will become most volatile.

Days like Monday are rare but extremely dangerous. Iowa is no stranger to severe weather, but the combination of factors coming together on Monday points toward an environment highly supportive of strong tornadoes, destructive hail, and widespread damaging winds. Continue to monitor trusted weather sources closely, stay prepared, and stay safe.

Severe Weather Outbreak Expected This Afternoon and Evening

A significant severe weather outbreak is expected to impact Iowa today, bringing the potential for destructive winds, large hail, and tornadoes, some of which could be strong. This system is fast-moving and will develop rapidly, meaning residents should stay alert and have multiple ways to receive weather warnings.

A powerful storm system is moving from the Central Plains into the Upper Midwest, creating conditions favorable for severe thunderstorms. As this system strengthens, it will produce intense wind gusts, significant instability, and heavy rainfall, increasing the risk of hazardous weather across the region.

The primary threats associated with this system include tornadoes, damaging winds, large hail, and flash flooding. Tornadoes could be strong and long-tracked, posing a considerable danger. Wind gusts of 80 to 100 mph are possible, capable of downing trees and power lines, causing structural damage, and making travel extremely hazardous. Hail as large as baseballs could impact some areas, leading to damage to vehicles, roofs, and crops. Additionally, heavy rainfall may result in localized flash flooding, particularly in low-lying and urban areas.

Severe storms are expected to develop early this afternoon, between 1:00 and 3:00 PM, across eastern Nebraska, Kansas, and Missouri before quickly moving into western and central Iowa by late afternoon. Storm activity will continue northeast toward eastern Iowa and the Illinois border into the evening hours. The most intense storms are likely between 4:00 and 10:00 PM, though severe weather could persist into the overnight hours.

Residents are urged to take necessary precautions to ensure their safety. It is essential to stay informed by monitoring weather updates frequently and enabling severe weather alerts on mobile devices. Those in the path of the storms should have a shelter plan in place, ensuring access to a basement or an interior room on the lowest floor of a sturdy building if a tornado warning is issued. Traveling during severe storms should be avoided whenever possible, as high winds, hail, and heavy rain can make road conditions dangerous. Additionally, outdoor objects should be secured to prevent them from becoming airborne in strong winds.

Given the potential for widespread and significant impacts, preparedness is critical. Residents are encouraged to take this threat seriously and remain vigilant throughout the day. If a warning is issued, immediate action should be taken to protect life and property.

For real-time updates and alerts, follow the National Weather Service, local emergency management agencies, and trusted weather sources.

Snow, Sleet, and Freezing Rain Followed by Arctic Cold Next Week

Short-Term Forecast (Today through Saturday)

Confidence: High to Medium

An Arctic high has moved across the Upper Midwest overnight, bringing some of the coldest air of the season to Iowa. However, temperatures will recover into the teens today as westerly flow aloft helps lift the cold air out of the region. Highs may be slightly lower in the south due to the reflective fresh snowpack, but temperatures will rise steadily through the day.

Later tonight, the surface ridge will exit, and the region will experience a significant warm air advection (WAA) as a deepening wave moves across the state. This will lead to the development of snow for much of the state, although the snow will be lighter than what was seen on Wednesday. Due to a warm nose aloft and limited ice introduction, snowfall will be mixed with sleet and/or freezing rain, especially along the Iowa-Missouri border. Snowfall totals will generally range from 1 to 2 inches across most of Iowa, with localized higher amounts possible in the northeast.

Saturday Forecast

Confidence: Medium

Saturday’s forecast remains uncertain due to the interaction of several waves over the Central Plains. Lee cyclogenesis will occur Friday night, which will bring the low-level jet (LLJ) into a WSW to ENE orientation by Saturday. The location and timing of this shift will affect the placement of the system's deformation axis and moisture plume, which will determine where the heaviest snow falls. The highest confidence of snowfall impacts is for eastern and southeast Iowa (50% confidence), but amounts will likely be limited due to the relatively low snow-to-liquid ratios (SLRs) associated with the warm air aloft.

Sunday and Beyond

Confidence: High

A weak wave is expected to bring light snow to the region Sunday, aided by weak lift and a prolonged residence time in the dendritic growth zone (DGZ). While this will not be a major snowfall event, it will bring additional light snow. The cold air will be reinforced, and lows will dip back below zero.

Looking ahead to early next week, another wave of colder air will arrive, making for an extremely cold stretch of days. Highs will be in the single digits, with lows in the teens below zero. It is highly likely that cold weather headlines will be needed due to the dangerously cold conditions.