Hail history for Lewis and Clark County, MT

Lewis and Clark County has 115 recorded hail events in the NOAA Storm Events Database — 84 of them 1″ or larger and 9 at 2″ or larger. The largest on record: 3.0″ (tea cup) on June 6, 1997.

Records 1950–present Data through April 2026 Peak month June

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 115 since 1955

1″ or larger 84 NWS severe threshold

2″ or larger 9 hen egg class and up

Largest recorded 3.0″ tea cup · June 6, 1997

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 Lewis and Clark County

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

Most recent recorded events

Latest 8 of 115 recorded events · data through April 2026
Date	Size	Comparable to
August 6, 2024	1.0″	Quarter
August 6, 2024	1.5″	Ping-pong ball
July 9, 2022	0.75″	Penny
July 8, 2022	1.0″	Quarter
July 8, 2022	1.0″	Quarter
July 21, 2021	1.0″	Quarter
July 21, 2021	1.0″	Quarter
May 19, 2020	1.0″	Quarter

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

From the storm reports

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

August 6, 2024 · 1.5″ (ping-pong ball)

Trained spotter reports hail of 1.5 inches in diameter.

August 15, 2014 · 1.75″ (golf ball)

Large hail, measuring 1.75 inches (golf ball sized), was reported along with heavy rain.

July 2, 2013 · 1.75″ (golf ball)

Hail measuring 1.75 inches was reported 9 mi NNE of Helena, MT.

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
3	3	4	9	17	47	24	8

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 Lewis and Clark County

Has it ever hailed in Lewis and Clark County?

Yes — 115 hail events have been recorded for Lewis and Clark County, MT in the NOAA Storm Events Database since 1955, including 84 of 1″ (quarter size) or larger.

When did it last hail in Lewis and Clark County?

The most recent recorded hail event for Lewis and Clark County, MT is August 6, 2024, 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 Lewis and Clark County?

3.0″ (tea cup), recorded on June 6, 1997. 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 Montana hail history

All 56 Montana 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.