HailHistoryHail by countyMinnesota › Rock County

Minnesota · county FIPS 27133

Hail history for Rock County, MN

Rock County has 137 recorded hail events in the NOAA Storm Events Database — 70 of them 1″ or larger and 6 at 2″ or larger. The largest on record: 4.0″ (softball) on June 12, 1994.

Records 1950–present Data through April 2026 Peak month June
Core sample · every recorded event, 1955–2026
1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s 1955 through 2026 largest · 4.0″ softball June 12, 1994

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 137 since 1956
1″ or larger 70 NWS severe threshold
2″ or larger 6 hen egg class and up
Largest recorded 4.0 softball · June 12, 1994
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 Rock County

Jan Feb 1 Mar 14 Apr 21 May 40 Jun 33 Jul 19 Aug 5 Sep 2 Oct 2 Nov Dec

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

Most recent recorded events

Latest 8 of 137 recorded events · data through April 2026
DateSizeComparable to
1.5″ Ping-pong ball
1.25″ Half dollar
1.0″ Quarter
1.0″ Quarter
2.75″ Baseball
2.0″ Hen egg
1.0″ Quarter
1.0″ Quarter

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

From the storm reports

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

· 1.5″ (ping-pong ball)

Hail occurred for 5 to 10 minutes, largest briefly up to ping-pong ball size.

· 2.75″ (baseball)

A very non-uniform hailstone measured at 2.8 inches at its widest.

· 1.75″ (golf ball)

Golf ball size hail caused an unknown amount of damage to vehicles.

Events by decade

1950s1960s1970s1980s1990s2000s2010s2020s
111421603514

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 Rock County

Has it ever hailed in Rock County?

Yes — 137 hail events have been recorded for Rock County, MN in the NOAA Storm Events Database since 1956, including 70 of 1″ (quarter size) or larger.

When did it last hail in Rock County?

The most recent recorded hail event for Rock County, MN is April 13, 2026, with 1.5″ (ping-pong ball) 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 Rock County?

4.0″ (softball), recorded on June 12, 1994. 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 Minnesota hail history

All 87 Minnesota 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.