Hail history for Knox County, TN

Knox County has 169 recorded hail events in the NOAA Storm Events Database — 118 of them 1″ or larger and 9 at 2″ or larger. The largest on record: 3.0″ (tea cup) on May 21, 1998.

Records 1950–present Data through April 2026 Peak month May

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 169 since 1961

1″ or larger 118 NWS severe threshold

2″ or larger 9 hen egg class and up

Largest recorded 3.0″ tea cup · May 21, 1998

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 Knox County

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

Most recent recorded events

Latest 8 of 169 recorded events · data through April 2026
Date	Size	Comparable to
October 21, 2025	0.75″	Penny
September 4, 2025	1.0″	Quarter
September 4, 2025	0.75″	Penny
September 4, 2025	0.75″	Penny
September 4, 2025	0.75″	Penny
September 4, 2025	1.0″	Quarter
September 4, 2025	1.75″	Golf ball
September 4, 2025	1.5″	Ping-pong ball

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

From the storm reports

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

June 14, 2020 · 1.0″ (quarter)

Nickel size hail was reported.

April 27, 2011 · 2.75″ (baseball)

The public reported thunderstorms produced baseball-size hail 2 miles southeast of Knoxville damaging vehicles in the area.

April 27, 2011 · 2.0″ (hen egg)

A trained spotter reported thunderstorms produced 2 inch size hail 2 miles west of Knoxville.

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
0	5	2	2	43	43	45	29

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 Knox County

Has it ever hailed in Knox County?

Yes — 169 hail events have been recorded for Knox County, TN in the NOAA Storm Events Database since 1961, including 118 of 1″ (quarter size) or larger.

When did it last hail in Knox County?

The most recent recorded hail event for Knox County, TN is October 21, 2025, with 0.75″ (penny) 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 Knox County?

3.0″ (tea cup), recorded on May 21, 1998. 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 Tennessee hail history

All 95 Tennessee 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.