TL;DR

The NOAA Storm Prediction Center (SPC) has issued a Slight Risk for severe thunderstorms across northern Minnesota and southeastern Arizona today. Scattered storms are expected this afternoon and evening, with damaging wind gusts up to 75 mph, large hail, and an isolated tornado threat in Minnesota. A Marginal Risk extends across portions of the Northeast and central High Plains.

Where is the highest risk today?

Two distinct regions face a Slight Risk for severe weather on August 3, 2026, according to the SPC Day 1 Convective Outlook.

Northern Minnesota and the eastern Dakotas anchor the primary Slight Risk area in the Upper Midwest. This zone includes:

  • International Falls
  • Bemidji
  • Grand Forks, North Dakota
  • Portions of the Red River Valley

Southeastern Arizona and adjacent New Mexico comprise the second Slight Risk area, covering:

  • Tucson
  • Sierra Vista
  • Portions of the lower Sonoran Desert

Outside these core areas, a Marginal Risk extends across the northern Mid-Atlantic through western New England, as well as isolated portions of the central High Plains.

What's driving today's severe weather setup?

Upper Midwest

Early morning radar showed a loose cluster of thunderstorms over the Red River Valley, developing in response to isentropic lift downstream of an eastward-migrating mid-level speed max over the northern Rockies. These morning storms have reinforced a frontal zone draped southwest to northeast across the region.

According to the SPC outlook, "Heating in wake of early day cloud cover will foster moderate destabilization by mid afternoon as mid to upper-level flow gradually strengthens." The combination of moderate instability and strengthening wind shear will support organized thunderstorm development.

The SPC notes that "initial storms later today will likely pose a risk for severe gusts and large hail and perhaps a tornado if a couple of storms can acquire supercell characteristics and mature within a moist axis ahead of the front."

Southeastern Arizona

Very strong heating and orographic lift will drive scattered thunderstorm development by late afternoon into early evening across southeastern Arizona and southwestern New Mexico. Model guidance from MPAS and HREF indicates a belt of enhanced mid- to upper-level northeasterlies over northern Sonora extending into the region.

The SPC outlook warns that "severe gusts 60 to 75 mph will be the primary hazard" as storm clusters propagate on outflow into the lower deserts during the evening. Very steep 0-3 km lapse rates will support strong downdrafts capable of producing damaging winds.

Northern Mid-Atlantic and New England

A weak cold front trailing a deepening surface low over the lower St. Lawrence Valley will move across the region today. While weak mid-level lapse rates and early cloud cover may slow destabilization, strengthening deep-layer wind fields could support organized storms if sufficient heating occurs.

When will the storms hit?

Upper Midwest: Thunderstorm initiation is expected by mid-to-late afternoon, with the severe threat continuing into the evening hours. Storms will likely evolve from isolated supercells into small clusters as the evening progresses.

Southeastern Arizona: Scattered thunderstorms should develop by late afternoon, with clusters propagating into the lower deserts during the evening. The severe wind threat will be highest during the evening hours.

Northeast: Timing is more uncertain and dependent on whether sufficient destabilization occurs ahead of the cold front. Any severe storms would most likely develop during the afternoon and early evening.

Central High Plains: Isolated high-based storms will develop during the afternoon along a surface trough, moving slowly eastward before weakening by mid-evening.

What happened in the last 24 hours?

Yesterday's severe weather was dominated by damaging winds, with 38 wind reports across multiple states. Georgia led the nation with 15 wind damage reports, primarily from trees and power lines downed by thunderstorms during the afternoon and evening hours.

Two hail reports came from northwestern Minnesota, where quarter-size hail (1.50 inches) fell near Argyle and Grygla during the morning hours—a preview of today's setup in the same region.

Wind damage was also reported across North Dakota, New York, Pennsylvania, South Carolina, West Virginia, and Texas as scattered thunderstorms tracked across multiple regions.

Tomorrow's outlook

The SPC Day 2 outlook shows a Marginal Risk for portions of the Midwest, Great Lakes, Southeast, and Northeast on August 4. Severe weather coverage is expected to remain limited as upper-level flow patterns remain relatively weak across much of the Lower 48.

A separate Marginal Risk may develop across portions of Colorado and New Mexico as monsoon moisture continues to support afternoon and evening thunderstorms.

Safety reminders for today's storms

If you're in northern Minnesota, the eastern Dakotas, or southeastern Arizona today:

  • Monitor local NWS forecasts and radar throughout the afternoon
  • Have multiple ways to receive severe thunderstorm and tornado warnings
  • If a warning is issued for your location, move to a sturdy building immediately
  • Avoid being outdoors or in a vehicle when storms approach—wind gusts up to 75 mph can overturn vehicles and snap large tree limbs
  • Large hail can develop quickly in supercell thunderstorms; if you see a severe thunderstorm warning mentioning hail, get vehicles under cover if possible

Third-party weather apps are silenced by Do Not Disturb, though Wireless Emergency Alerts for tornado warnings still break through on most phones. For nighttime severe weather events, having a reliable way to receive warnings while asleep is critical.

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.