Hail history for Cook County, IL

Cook County has 643 recorded hail events in the NOAA Storm Events Database — 440 of them 1″ or larger and 25 at 2″ or larger. The largest on record: 2.75″ (baseball) on April 7, 2020.

Records 1950–present Data through April 2026 Peak month April

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 643 since 1955

1″ or larger 440 NWS severe threshold

2″ or larger 25 hen egg class and up

Largest recorded 2.75″ baseball · April 7, 2020

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 Cook County

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

Most recent recorded events

Latest 8 of 643 recorded events · data through April 2026
Date	Size	Comparable to
April 14, 2026	1.0″	Quarter
April 14, 2026	1.0″	Quarter
March 30, 2026	1.0″	Quarter
March 30, 2026	1.0″	Quarter
March 30, 2026	1.0″	Quarter
March 30, 2026	1.0″	Quarter
March 30, 2026	2.0″	Hen egg
March 30, 2026	1.25″	Half dollar

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

From the storm reports

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

March 10, 2026 · 2.0″ (hen egg)

A few 1 to 2 inch hail reports came out of LaGrange and Brookfield.

April 7, 2020 · 2.75″ (baseball)

Multiple reports of golf ball to baseball size hail were received from Evanston.

June 30, 2011 · 2.75″ (baseball)

Hail as large as baseballs was reported near 26th Street and Kedzie Avenue. Hundreds of vehicles were damaged including at least 130 police cars that suffered broken windshields and smashed rooftop lights.

Events by decade

1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s
8	23	20	19	34	206	206	127

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 Cook County

Has it ever hailed in Cook County?

Yes — 643 hail events have been recorded for Cook County, IL in the NOAA Storm Events Database since 1955, including 440 of 1″ (quarter size) or larger.

When did it last hail in Cook County?

The most recent recorded hail event for Cook County, IL is April 14, 2026, 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 Cook County?

2.75″ (baseball), recorded on April 7, 2020. 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 Illinois hail history

All 102 Illinois 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.