Ontario, California hail history
10
Days with hail on record
0
Carried by two or more independent sources
10
Measured by a person or an instrument
0.50in
Largest measured, Feb 2023
What was searched
| Evidence | Sources | Record from | Reports within 10 mi |
|---|---|---|---|
| Ground observation | ×6 | 1996 | 12 |
| Radar detection | ×1 | When an address is run | None |
| Official NWS warning | ×1 | When an address is run | None |
| Federal declaration | ×1 | When an address is run | None |
Hail days by year in Ontario, CA
Measured Detected only 1.00″ or more
Each mark is one day with hail on record, placed where it fell in the year, and each opens the record for that day. A row with nothing on it is a year with nothing on record.
Best-attested hail storms near Ontario
Most sources first
| Date | Largest | Measured | Reports | Sources |
|---|---|---|---|---|
| 23 Feb 2023 | 0.50″ | 0.50″ | 2 | ×1 |
| 22 Dec 2023 | 0.25″ | 0.25″ | 1 | ×1 |
| 15 Mar 2021 | 0.25″ | 0.25″ | 1 | ×1 |
| 08 Apr 2020 | 0.25″ | 0.25″ | 1 | ×1 |
| 23 Jan 2017 | 0.25″ | 0.25″ | 1 | ×1 |
| 06 May 2016 | 0.25″ | 0.25″ | 2 | ×1 |
| 15 Feb 2012 | 0.25″ | 0.25″ | 1 | ×1 |
| 15 Dec 2011 | 0.25″ | 0.25″ | 1 | ×1 |
Sources per hail day near Ontario
- One source
- 10
- Two
- 0
- Three or more
- 0
A day carried by one report is a report. A day that radar, a trained observer and a warning all describe is a storm, and it is the kind of day a file can rest on. Every report on these days keeps its own source.
- Wind days
- 115
- Tornado days
- 0
On record within the same 10 miles. Wind history for Ontario. A report for an address searches every family.
Largest hail recorded near Ontario, CA
Measured Detected, not measured
| Date | Size | Evidence | From centre |
|---|---|---|---|
| 23 Feb 2023 | 0.50″ | Ground observation | 7.8 mi SW |
| 16 Feb 2009 | 0.25″ | Ground observation | 9.6 mi WSW |
| 06 Nov 2011 | 0.25″ | Ground observation | 0.9 mi NNW |
| 15 Dec 2011 | 0.25″ | Ground observation | 7.4 mi NNE |
| 15 Feb 2012 | 0.25″ | Ground observation | 9.6 mi WSW |
| 06 May 2016 | 0.25″ | Ground observation | 3.0 mi NW |
| 06 May 2016 | 0.25″ | Ground observation | 1.6 mi N |
| 23 Jan 2017 | 0.25″ | Ground observation | 9.3 mi WSW |
The finder lists every day with hail on record within 10 miles of an address in the last 2 years, ranked by how many independent sources carried it, so the day a file names is a day the record holds.
A roof has an age. The record has its days: roof age and hail exposure counts every hail day on record near an address since the year the roof went on.
Get the hail report for an address in Ontario, CA
Everything above is the record around Ontario: enough to know there is something to cite, and from where. None of it says what reached one roof.
Run the address and the same archive is searched at the property: the storm, the date, the measured size, the distance and bearing from the roof, and the federal record each figure came from, in a document that states its own method. About a minute.
Questions about hail in Ontario, CA
How many hail days has Ontario, CA had on record?
10 days with hail within 10 miles of the centre of Ontario since 1996, 0 of them carried by two or more independent sources and 10 with hail measured by a person or an instrument.
When did it last hail in Ontario, CA?
The most recent hail on record near Ontario fell on 22 December 2023, with its largest report 0.25 inches, measured.
What is the largest hail measured near Ontario?
0.50 inches, measured on 23 February 2023, 7.8 miles SW of the centre of Ontario.
How do I get a hail report for an address in Ontario?
Enter the address on this page. The Titan Weather report is the paid document: it searches the same archive at the property and lists every hail report with its date, measured size, distance and bearing from the roof, and the federal source it came from. The date-of-loss finder is free and lists the hail days on record near Ontario first.
Hail history near Ontario
Within 30 miles of Ontario, nearest first. A storm that crossed one of these crossed the others, and their counts overlap.
- Chino 5 mi 14 days
- Eastvale 5 mi 12 days
- Montclair 6 mi 8 days
- Upland 6 mi 6 days
- Rancho Cucamonga 7 mi 5 days
- Jurupa Valley 8 mi 6 days
- Norco 8 mi 9 days
- Claremont 9 mi 5 days
How this page is made
- What counted
- Every hail report in the archive with a point within 10 miles of the Census centre of Ontario (34.0377, -117.6044). A hail day is a calendar date with at least one report: four sources describing one storm are one afternoon of hail, not four.
- Measured and detected
- A report from a person or an instrument is measured. A radar-derived size is a detection and is marked as one, here and in every document we issue. The two are never added together.
- Severe
- A day counts as severe when its largest report reached 1.00″, the National Weather Service criterion. Smaller hail is still on the record, and still on this page.
- What this is not
- Neighbouring places share reports, so counts are not exclusive. This page is the record around a place; it is not a report on any property, and it states no opinion about one.
- Terms used on this page
- Storm day, independent source, measured and detected: each term this page uses is defined in the glossary as the report prints it.
- Alerts
- The next storm day to enter the record near Ontario can be sent to your inbox, with the figures its page states and nothing about any roof.
- The record
- Searched from 1996 to today. Compiled 24 August 2026 and rebuilt daily as the archive deepens. Records are reproduced as the federal sources published them. The coverage page states what the record holds, by kind and by year.
About this record
Everything here is reproduced from public federal and volunteer weather records, as the agencies and observer networks that publish them released it. Titan Weather compiles the record; it does not observe the weather, and it is not affiliated with any source it cites.
No archive holds everything. Storms cross places where nobody is standing, instruments and spotters cover some areas better than others, sources revise their records, and recent reports can take weeks to arrive and settle. Where this page shows nothing, nothing was found in the sources searched, within the period and area it states. That is not a finding that no weather occurred.
These pages describe the public record near a place or on a date. They do not establish what reached any particular property, and nothing here is insurance, legal or engineering advice.