Hail history for Jefferson County, CO

Jefferson County has 506 recorded hail events in the NOAA Storm Events Database — 355 of them 1″ or larger and 25 at 2″ or larger. The largest on record: 3.0″ (tea cup) on June 13, 1984.

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 506 since 1960

1″ or larger 355 NWS severe threshold

2″ or larger 25 hen egg class and up

Largest recorded 3.0″ tea cup · June 13, 1984

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: June.

Most recent recorded events

Latest 8 of 506 recorded events · data through April 2026
Date	Size	Comparable to
August 23, 2025	1.0″	Quarter
August 23, 2025	1.5″	Ping-pong ball
August 23, 2025	1.0″	Quarter
August 23, 2025	1.0″	Quarter
August 23, 2025	0.75″	Penny
August 10, 2025	0.75″	Penny
July 6, 2025	1.5″	Ping-pong ball
July 6, 2025	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).

August 10, 2025 · 0.75″ (penny)

The report was from mPING.

June 22, 2023 · 2.0″ (hen egg)

Large hail damaged a roof and window screens.

May 8, 2017 · 2.75″ (baseball)

The estimated damage is for the entire episode.

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
0	8	12	66	82	126	126	86

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 — 506 hail events have been recorded for Jefferson County, CO in the NOAA Storm Events Database since 1960, including 355 of 1″ (quarter size) or larger.

When did it last hail in Jefferson County?

The most recent recorded hail event for Jefferson County, CO is August 23, 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?

3.0″ (tea cup), recorded on June 13, 1984. 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 Colorado hail history

All 64 Colorado 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.