Storm reports for August 21, 2017

IndependentNot affiliated with NOAA or the National Weather Service. Source: NOAA Storm Prediction Center storm reports. Data through November 6, 2026. Methodology

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Other storms on August 21 →

On August 21, 2017, 26 hail, 41 damaging-wind and 2 tornado reports were logged across 12 states. The largest hail reported was 2.00″ (hen egg size) in Hutchinson County, SD.

Storm day runs 7 a.m. to 7 a.m. Eastern (12:00–12:00 UTC), the convention the Storm Prediction Center uses. Radar hail estimates start October 2019.

Storm reports by state

Cities with hail reported within 5 miles

Hail reports (26)

Damage, injuries and deaths

National Weather Service offices recorded about $14,000 in property damage and $12,000 in crop damage from hail, thunderstorm wind and tornadoes across the US on this storm day (70 events in 12 states). Injuries and deaths are those the events caused directly.

What the National Weather Service wrote

• Tioga County, NY (near West Candor) · Thunderstorm wind 63 mph · $5,000
  “A thunderstorm moved across the region and became severe. This thunderstorm produced severe winds and knocked over a few trees between Spencer and Candor.”
• Boone County, IA (near Napier) · Tornado EF0 · $5,000
  “This tornado was found in hi-resolution satellite imagery and crossed mostly open farm fields. The tornado did damage trees across the corner of one farmstead but otherwise did little other damage. This tornado continued into Story county.”
• Clearfield County, PA (near Riverview) · Thunderstorm wind 60 mph · $2,000
  “A severe thunderstorm producing winds estimated near 60 mph knocked down two trees in Clearfield Borough.”
• Indiana County, PA (near Shelocta) · Thunderstorm wind 58 mph · $1,000
  “The public reported several trees down in Shelocta.”
• Bedford County, VA (near Forest) · Thunderstorm wind 58 mph · $1,000
  “Thunderstorm outflow winds, along with heavy water loading from torrential rains, brought down two trees within the community of Forest, VA. Damage values are estimated.”
• Lyon County, KS (near Emporia) · Thunderstorm wind 81 mph
  “Report via social media picture. 10 inch diameter tree branch split from the main trunk. Radar estimated time.”

Event narratives from NWS Storm Data, shortened. Up to six per day, chosen by deaths, injuries, damage and size.

Source: NOAA National Centers for Environmental Information (NCEI), Storm Events Database, as entered by National Weather Service offices; data through July 31, 2026. Damage is in dollars of the year, not adjusted for inflation.

Guides: What radar-estimated hail (MESH) is and isn't · Storm reports: preliminary vs final