Hail history for Jefferson County, MT

Jefferson County has 56 recorded hail events in the NOAA Storm Events Database — 44 of them 1″ or larger and 2 at 2″ or larger. The largest on record: 2.0″ (hen egg) on June 25, 1996.

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 56 since 1959

1″ or larger 44 NWS severe threshold

2″ or larger 2 hen egg class and up

Largest recorded 2.0″ hen egg · June 25, 1996

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 Jefferson County

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

Most recent recorded events

Latest 8 of 56 recorded events · data through April 2026
Date	Size	Comparable to
July 28, 2025	1.0″	Quarter
July 6, 2023	1.0″	Quarter
July 24, 2022	1.0″	Quarter
July 6, 2022	0.88″	Nickel
August 10, 2019	1.5″	Ping-pong ball
August 10, 2019	1.5″	Ping-pong ball
August 10, 2019	1.5″	Ping-pong ball
August 10, 2019	1.0″	Quarter

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

From the storm reports

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

July 28, 2025 · 1.0″ (quarter)

Trained spotter reports hail slightly larger than quarter sized.

August 10, 2019 · 1.5″ (ping-pong ball)

A trained spotter reports hail of 1.5 inches in diameter.

August 4, 2001 · 1.75″ (golf ball)

Reported by general public at campground at Basin 14 SW...Golf ball sized hail accumulated to 4 inches deep.

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
1	2	3	0	3	14	29	4

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 Jefferson County

Has it ever hailed in Jefferson County?

Yes — 56 hail events have been recorded for Jefferson County, MT in the NOAA Storm Events Database since 1959, including 44 of 1″ (quarter size) or larger.

When did it last hail in Jefferson County?

The most recent recorded hail event for Jefferson County, MT is July 28, 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 Jefferson County?

2.0″ (hen egg), recorded on June 25, 1996. Hail that size meets or exceeds the National Weather Service severe threshold. 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.