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.

Winter Storm Warning: Significant Snowfall Expected Across Much of Iowa

Acute CriticalAlert

Heavy Snowfall Expected: Significant snow will impact much of Iowa, with the highest accumulations (5-8 inches) expected in southern and central Iowa.

Winter Storm Warning: A Winter Storm Warning is in effect from midnight tonight until midnight Wednesday night for southern and central Iowa.

Hazardous Travel: Snow-covered and slick roads will create hazardous travel conditions, especially during the Wednesday morning and evening commutes.

Snow Rates: Snow will fall at rates of a quarter to half an inch per hour, with some periods seeing rates of up to three-quarters of an inch per hour.

FORECAST OVERVIEW

Snow will begin over far western Iowa around midnight tonight, spreading into central and eastern Iowa after midnight. The heaviest snow will accumulate in southern and central Iowa, where 5 to 8 inches are expected. Snowfall rates will vary but will generally be between a quarter to half an inch per hour, with some localized periods of heavier snow. Visibility will be reduced in the falling snow, but blowing snow is not expected to be a significant issue, as winds will remain relatively light, averaging 10 to 15 mph.

The snow will taper off from west to east late Wednesday afternoon into Wednesday evening, but hazardous travel conditions will persist through the day, particularly during the morning and evening commutes.

WINTER STORM WARNING DETAILS

What: Heavy snow expected, with total accumulations between 5 and 8 inches in the warning area.

When: Midnight tonight to midnight Wednesday night.

Impacts: Travel will be very difficult, particularly during the Wednesday morning and evening commutes. Roads will be snow-covered and slick, creating hazardous driving conditions.

PRECAUTIONARY ACTIONS

Travel Safety: If you must travel, keep an extra flashlight, food, and water in your vehicle in case of emergency.

Stay Informed: For the latest travel conditions and road updates, check the Iowa 511 app, visit www.511ia.org, or dial 511.

Prepare for a challenging commute as snow impacts much of Iowa. Make sure to stay informed and take necessary precautions to ensure your safety during this winter weather event.

Light Snow Today, Cold Front Arriving, and a Warm-Up Next Week

KEY MESSAGES

Light Snow Today: Light snow continues across central Iowa, with minor accumulations expected, generally half an inch or less. Snow should move out of the area over the next few hours.

Cold Front Tonight: A cold front will push through the state this evening, bringing a brief chance for flurries or light snow showers, followed by colder air overnight.

Weekend Weather: Temperatures will fluctuate this weekend as a broad upper trough remains over the eastern U.S., but precipitation chances are limited.

Warm-Up Next Week: A warm-up is expected by Tuesday and Wednesday next week, with above-normal temperatures as the polar jet lifts north.

Short-Term Forecast (Today through Tonight)

Confidence: High

Broad northwest flow aloft continues across the central U.S., maintaining a large longwave trough over eastern North America. This has led to the development of light snow across central Iowa, with visibility dropping to below 2 miles in some areas and minor accumulations of less than half an inch. The snow will move east and out of the state as the warm advection and associated isentropic lift weaken. However, some light snow or flurries may persist through the day, particularly in areas affected by lingering mid-level forcing. While snowfall will remain light, there could be some minor impacts, but no significant accumulation is expected.

Temperatures will continue to rise today ahead of a cold front. The air mass over Nebraska and South Dakota is already in the upper 20s to near 30°F, and this will push temperatures into the low 30s across much of southern and western Iowa. The front is expected to arrive this evening, bringing a brief window of flurries or light snow showers along with it. As the front passes, colder air will move in overnight, with temperatures dropping for Thursday.

Extended Forecast (Thursday through the Weekend)

Confidence: Medium

The broad upper trough across the eastern U.S. will gradually lift northeast through the weekend, bringing a roller-coaster of temperatures. Several shortwaves will pass through the backside of the trough, potentially impacting the Midwest, but precipitation chances remain limited due to the dry nature of the airmass. The temperatures will fluctuate, with brief cold spells as the shortwaves move through, followed by some warmer air pushing in from the west.

By the middle of next week, a shift in the upper flow will allow warmer air to move across Iowa, with temperatures rising above normal for the first time in a while. The warmer air will spread in by Tuesday and Wednesday, with highs likely reaching above-average levels. This will help ease the cold snap, but the overall pattern will keep precipitation chances at bay, with any systems remaining mostly to the north of Iowa.