Hail history for Lyman County, SD

Lyman County has 234 recorded hail events in the NOAA Storm Events Database — 172 of them 1″ or larger and 22 at 2″ or larger. The largest on record: 8.0″ (grapefruit) on July 23, 2010.

Records 1950–present Data through April 2026 Peak month July

Core sample · every recorded event, 1955–2026

Mark size = measured hail diameter; slivers are events with no recorded size. Amber ≥2″, red ≥2.75″ (baseball class). Denser recent decades partly reflect better reporting, not only more storms.

Recorded events 234 since 1957

1″ or larger 172 NWS severe threshold

2″ or larger 22 hen egg class and up

Largest recorded 8.0″ grapefruit · July 23, 2010

Read the record honestly: Storm Events contains what was reported to the National Weather Service. Sparse or rural counties under-report, and coverage improved sharply after the mid-1990s — a quiet-looking stretch is not proof nothing fell.

When it hails in Lyman County

Recorded events by month, 1950–present. The amber bar marks Lyman County's peak: July.

Most recent recorded events

Latest 8 of 234 recorded events · data through April 2026
Date	Size	Comparable to
August 13, 2025	1.0″	Quarter
August 3, 2025	1.25″	Half dollar
August 3, 2025	1.0″	Quarter
July 29, 2025	1.0″	Quarter
July 28, 2025	1.75″	Golf ball
July 9, 2025	2.5″	Tennis ball
June 27, 2025	1.0″	Quarter
August 4, 2023	1.25″	Half dollar

Looking for a specific storm? Use the did-it-hail date lookup for Lyman County.

From the storm reports

Narratives as filed with the NOAA Storm Events Database (public records; lightly trimmed for length).

August 3, 2025 · 1.0″ (quarter)

Hail measuring one inch in diameter was reported nine miles southwest of Oacoma.

August 6, 2019 · 2.75″ (baseball)

Tennis to baseball size hail damaged homes and vehicle windows.

July 23, 2010 · 8.0″ (grapefruit)

The eight inch diameter hailstone was a United States record. The hailstone also had a circumference of 18.625 inches and weighed 1.9375 pounds. The hailstone broke the previous United States record for diameter (7.0 inches - 22 June 2003 in Aurora, NE) and weight (1.67 pounds - 3 September 1970 in Coffeyville, KS). The Aurora, Nebraska hailstone will retain the record for circumference (18.75 inches).

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
3	3	7	8	28	78	84	23

The climb across decades is largely a reporting story: spotter networks, radar, and digital filing pulled far more storms into the record after the 1990s.

Questions about hail in Lyman County

Has it ever hailed in Lyman County?

Yes — 234 hail events have been recorded for Lyman County, SD in the NOAA Storm Events Database since 1957, including 172 of 1″ (quarter size) or larger.

When did it last hail in Lyman County?

The most recent recorded hail event for Lyman County, SD is August 13, 2025, with 1.0″ (quarter) hail. The database is currently updated through April 2026, so a storm from the last few weeks may not appear yet. To check a specific day, use the did-it-hail date lookup.

What is the largest hail ever recorded in Lyman County?

8.0″ (grapefruit), recorded on July 23, 2010. Hail that size is destructive-class and typically damages roofs, vehicles, and siding. See how big that really is on the actual-size hail chart.

Does a recorded hail event mean my roof was damaged?

No. This page reports storm records, not damage. Hail size and damage vary block by block within a county, and only an inspection can establish what happened to a specific roof. If you suspect damage, talk to your insurer or a licensed roofer — they can pull the same NOAA records for your claim.

More South Dakota hail history

All 66 South Dakota counties, ranked by recorded hail →

Source: NOAA/NCEI Storm Events Database, public domain, updated monthly by NCEI — this site's copy runs through April 2026. HailHistory reports records; it does not give insurance advice or assess damage.