August 11, 2026 Storm Near Rapid City, SD: Reported Hail Sizes

On August 11, 2026, storm reports placed hail up to 3.60 in. within 25 miles of Rapid City, South Dakota; the record shows no wind reports there that day. 31 reports meet National Weather Service severe criteria: hail 1.00 in. or larger, or a gust of 58 mph or more.

Hail reports near Rapid City on Aug 11, 2026

32 hail reports fall within 25 miles of the Rapid City city center on Aug 11, 2026. The closest value meeting NWS severe criteria came from 3 ENE Rockerville, 7.5 miles southwest of Rapid City: 1.75 in. hail (golf ball size).

  • 3.60 in. hail — 2 SSW Hermosa, 18 mi S — NWS Local Storm Report (Storm Chaser, NWS office UNR) — meets NWS severe criteria
  • 3.50 in. hail — Hermosa, 16 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.40 in. hail — 3 SSW Hermosa, 18.7 mi S — NWS Local Storm Report (Storm Chaser, NWS office UNR) — meets NWS severe criteria
  • 3.25 in. hail — 4 W Hermosa, 16.2 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.00 in. hail (tea cup size) — 3 ESE Rockerville, 10.6 mi SW — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.00 in. hail (tea cup size) — 1 NNE Hayward, 13.5 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.00 in. hail (tea cup size) — 4 WNW Hermosa, 14.8 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.00 in. hail (tea cup size) — 7 W Hermosa, 16.9 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 3.00 in. hail (tea cup size) — 2 SW Hermosa, 17.3 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 2.75 in. hail (baseball size) — 1 E Hayward, 14.6 mi S — NWS Local Storm Report (Broadcast Media, NWS office UNR) — meets NWS severe criteria
  • 2.75 in. hail (baseball size) — 5 WNW Hermosa, 15.1 mi S — NWS Local Storm Report (Trained Spotter, NWS office UNR) — meets NWS severe criteria
  • 2.75 in. hail (baseball size) — 1 WNW Hermosa, 15.3 mi S — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 2.50 in. hail (tennis ball size) — Rockerville, 10.4 mi SW — NWS Local Storm Report (NWS Employee, NWS office UNR) — meets NWS severe criteria
  • 2.50 in. hail (tennis ball size) — 1 S Rockerville, 11.5 mi SW — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria
  • 2.50 in. hail (tennis ball size) — 3 NNW Johnson Siding, 12.5 mi W — NWS Local Storm Report (Public, NWS office UNR) — meets NWS severe criteria

Plus 17 more reports within 25 miles that day.

Measured station gusts near Rapid City

No airport weather station (ASOS/AWOS) within 25 miles of Rapid City logged a gust of 50 mph or more on August 11, 2026. The record near Rapid City that day is driven by hail reports.

What the Aug 11, 2026 numbers mean

The National Weather Service defines a severe thunderstorm as one that produces hail at least 1 inch in diameter, winds of at least 58 mph, or a tornado (NWS glossary). The same 58 mph gust mark triggers an NWS High Wind Warning for wind outside thunderstorms. The largest hail reported near Rapid City that day, 3.60 in., meets the NWS hail criterion.

StormAuditor also uses lower screening thresholds — hail 0.75 in. and wind 45 mph — to flag dates worth researching at an address. Screening thresholds are not NWS severe criteria. Hail sizes compare to everyday objects in the Hail Size Guide; gust speeds are explained in the Wind Speed Guide.

Check your Rapid City address for Aug 11, 2026

Storm reports are points on a map; a property sits somewhere between them. Run the Free Report Snapshot for any Rapid City address: a free YES/NO on whether the public record shows estimated wind of 45 mph or more or hail of 0.75 in. or larger at the property itself. Those are StormAuditor screening thresholds.

For the numbers, the Single Weather Report ($2.99) lists the estimated peak gust and estimated maximum hail size for every qualifying storm date at one address, including August 11, 2026 when the estimate there clears the screening thresholds. The Audit Report shows the evidence and arithmetic behind the estimate for a single date.

Other South Dakota cities with NWS severe reports on Aug 11, 2026

1 other city in South Dakota had a report meeting NWS severe criteria within 25 miles the same day:

More storm days near Rapid City and in South Dakota

How these numbers are counted

This page and the Rapid City city page share one set of definitions:

  • This page (NWS severe): Every NWS hail and wind report within 25 miles of Rapid City that day (StormAuditor records reports from hail 0.50 in. and wind 40 mph), plus airport weather-station gusts of 50 mph or more. The page exists because at least one report or station gust met NWS severe criteria (hail 1.00 in.+ or wind 58 mph+), at least two separate observations were logged, and the day ranks among the most significant.
  • Each observation counts once: A storm report that relays an airport weather station's reading (the same station, the same gust and the same time) counts once, as the station reading. Reports merge only when they are copies of one report: the identical report repeated, or the same report arriving through another feed (SPC or NCEI). Different reports from the same spot, such as two hail sizes reported at one place, count separately.
  • Rapid City storm-day table: The city page lists storm days: hail 0.75 in.+ or wind 45 mph+ within 25 miles in the last 12 months (StormAuditor screening thresholds; reports and station gusts, never warnings alone). When this date is in that table, it shows the same largest hail and strongest gust as this page; a value below the screening thresholds shows as a dash.
  • Events (12-month counts): The Rapid City city page also counts events, which include NWS warnings. Events measure how busy the area was, not whether a storm hit, so they are not compared with the report counts here.

Full method: Methodology and Data Sources.

Sources for this page

Reports come from NWS Local Storm Reports. StormAuditor merges copies of the same report that arrive through more than one feed, counts a storm report that relays an airport station's reading once, as the station reading, measures each distance from the Rapid City city center, and compiled this record on October 7, 2026. See Data Sources and Methodology.

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