What you need to know

The Storm Prediction Center has issued a Slight Risk for severe thunderstorms across parts of Nebraska and South Dakota today, with damaging winds and isolated large hail expected this afternoon and evening. A cold front moving through the central Plains will trigger storms in an unstable, moisture-rich environment. Isolated severe wind gusts are also possible across parts of the Southeast and Florida.

Severe weather will unfold across multiple regions today, driven by a cold front sweeping through the central Plains and scattered convection across the Southeast. The highest threat sits across Nebraska and South Dakota, where the NOAA Storm Prediction Center (SPC) has outlined a Slight Risk—the third level on the five-tier scale.

Yesterday saw widespread wind activity across the nation, with 106 wind reports. Today's setup shifts the focus to the central Plains, where atmospheric ingredients are aligning for organized severe storms.

Where is the highest risk today?

The Slight Risk area covers parts of Nebraska and South Dakota, extending into portions of Kansas, Missouri, Colorado, Wyoming, and Montana. Within this zone, south-central South Dakota and central Nebraska face the greatest threat for supercells capable of producing large hail early in the storm cycle, transitioning to damaging winds as storms cluster and grow upscale this evening.

Key cities in or near the Slight Risk include:

  • Lincoln, Nebraska
  • Omaha, Nebraska
  • Sioux Falls, South Dakota
  • Grand Island, Nebraska
  • Rapid City, South Dakota

Outside the Slight Risk, Marginal Risk areas extend across eastern Colorado, western Kansas, eastern Montana, and portions of the Southeast including northern Florida and southern Georgia.

What's driving today's severe weather?

An amplifying shortwave trough currently positioned over Wyoming is moving east and southeast toward the middle Missouri Valley and Upper Midwest. A cold front tied to this system will accelerate southeastward later today and tonight, plowing into a moisture-rich air mass that has built across Kansas, Nebraska, and South Dakota.

According to the SPC's Day 1 outlook, early-day cloud cover and scattered precipitation will diminish later this morning, allowing for "ample insolation near a surface trough and ahead of the front." Translation: sunshine will heat the lower atmosphere, destabilizing the air mass and providing fuel for thunderstorms.

Mid-level winds remain relatively weak, but effective wind shear—the change in wind speed and direction with height—will be sufficient to support a few supercells during the initial development phase. The SPC notes that "a few initial supercells could occur in vicinity of south-central South Dakota into central Nebraska amidst somewhat stronger effective shear."

As the evening progresses, storms are expected to cluster and organize into a larger complex, aided by an increasingly strong southwesterly low-level jet. This transition from discrete supercells to an organized line or mesoscale convective system will shift the primary threat from hail to damaging winds.

When will the storms hit?

Central and Northern Plains: Convective initiation is expected during the mid to late afternoon across south-central South Dakota and central Nebraska. Initial supercells may produce isolated large hail between roughly 3 PM and 6 PM local time. As storms cluster and grow upscale through the evening—particularly after 6 PM—damaging wind gusts will become the primary concern. The organized system will progress southeastward tonight, continuing the wind threat into the overnight hours.

High Plains (Colorado, Montana, Wyoming): Topographic forcing will trigger isolated to scattered storms during the mid to late afternoon across eastern Colorado, western Kansas, and eastern Montana. Some storms may also spread southward from southern Saskatchewan into northeast Montana. These storms will move east-southeastward into the lower elevations through the evening, capable of localized strong to severe wind gusts and hail.

Southeast and Florida: Scattered thunderstorms are already underway this morning across northern Florida and nearby offshore waters. Additional development is expected near and just south of a west-to-east oriented front, where stronger heating and destabilization will occur. The strongest storms will be capable of isolated damaging wind gusts through late afternoon and early evening.

What hazards should you prepare for?

Damaging winds are the primary threat today, especially across Nebraska and South Dakota this evening as storms grow upscale. The SPC emphasizes that "damaging winds should be an increasing and more common concern with the expectation that storms will cluster, grow upscale, and progress southeastward this evening."

Yesterday's severe weather activity underscores the wind threat: 106 wind reports were logged across multiple states, including numerous downed trees and power lines across Georgia, Florida, Alabama, and Montana. Wind gusts reached 69 mph near Sibley Peak, Wyoming, and 67 mph near Strasburg, Colorado.

Isolated large hail will be possible early in the storm lifecycle across south-central South Dakota and central Nebraska, particularly with any supercells that develop ahead of the main line. Hail reports from the past 24 hours were limited—just two reports, including 1.75-inch hail near Rosita, Colorado—but today's environment supports larger stones where supercells can sustain themselves.

Tornadoes are not a significant concern today. The SPC outlook does not highlight tornado probabilities, and mid-level winds remain too weak to support widespread rotating storms. Focus your preparation on wind and hail.

What should you do?

If you're in the Slight Risk area across Nebraska or South Dakota:

  • Monitor radar and warnings closely this afternoon and evening. Conditions can deteriorate quickly as storms develop.
  • Secure outdoor objects that could become projectiles in high winds—patio furniture, trampolines, trash cans.
  • Identify your shelter location. Move to an interior room on the lowest floor if a severe thunderstorm warning is issued for your area. Stay away from windows.
  • Charge devices now. Power outages are possible with damaging winds and downed trees.
  • If you're driving, avoid being on the road during peak storm hours (late afternoon through tonight). Pull over and wait out severe storms rather than driving through them.

For those in the Southeast and Florida, remain weather-aware through the afternoon. Isolated damaging wind gusts are possible with the stronger storms.

Nighttime severe weather presents unique challenges. Most weather apps are silenced by Do Not Disturb mode on smartphones, though Wireless Emergency Alerts (WEA) for severe thunderstorm and tornado warnings still break through on most phones. If storms are expected overnight in your area, consider keeping your phone's ringer on or using a NOAA Weather Radio.

What does tomorrow look like?

The SPC Day 2 outlook (valid Friday, July 31) shows a Marginal Risk across portions of Missouri, Mississippi, Iowa, and Colorado as the system continues east. Severe weather potential will be lower than today, but scattered storms with isolated severe wind gusts and hail remain possible.

Day 3 (Saturday, August 1) maintains a Marginal Risk across Tennessee, Ohio, New Mexico, and parts of the Great Lakes and Gulf Coast as the pattern remains active but less organized.

Stay weather-aware today, especially if you're across the central Plains. Damaging winds and hail are both on the table, and conditions will evolve quickly this afternoon.

VORTEX is a free web app at vortexintel.app that monitors severe weather nationwide. Pro ($4.99/month) places phone calls to your phone when a tornado or flash flood warning is issued for a location you care about — calls can ring through Do Not Disturb once you enable Emergency Bypass for the number, unlike most third-party app notifications.