NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit San Ramon, CA
Every tropical system within 75 miles since 1851 and every tornado within 25 miles since 1950.
Data: NOAA NHC HURDAT2 and NOAA SPC tornado and hail reports, through 2025 · Updated
No tropical storm or hurricane has passed within 75 miles of San Ramon, California since records began in 1851. Since 1950, 10 tornadoes have touched down within 25 miles, 0 of them rated EF3 or stronger.
- Hurricanes
- 0
- Tropical storms
- 0
- Tornadoes
- 10
- EF3 or stronger
- 0
within 75 mi, since 1851
below hurricane strength
within 25 mi, since 1950
no recorded deaths
What the records show for San Ramon
The strongest of the 10 tornadoes within 25 miles was an F2 on January 11, 1951; its path came within 24 miles. Of the 10, none had a path within 5 miles of the city centre, and one has come since 2000. January has had the most tornadoes, 3. The most recent tornado was on January 23, 2010. Of the 705 California cities on this site, 59% have more tornadoes within 25 miles than San Ramon. Hail has been reported within 10 miles 8 times since 2018, with stones up to 0.25 inches. San Ramon has more hail reports within 10 miles than 82% of the 705 California cities.
Compare San Ramon's storm record with another city →
Tornadoes within 25 miles of San Ramon
By decade
- 2010s1
- 1990s3
- 1980s4
- 1950s2
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Jan 11, 1951 | F2 | 24 mi | 5.7 mi | 0 / 0 |
| Jan 23, 2010 | EF1 | 14 mi | 1.64 mi | 0 / 0 |
| Jan 14, 1980 | F1 | 20 mi | 0.3 mi | 0 / 1 |
| Apr 1, 1958 | F1 | 24 mi | 0.2 mi | 0 / 0 |
| Feb 19, 1998 | F0 | 18 mi | 0.2 mi | 0 / 0 |
| Apr 25, 1994 | F0 | 11 mi | 0.7 mi | 0 / 0 |
| Dec 17, 1992 | F0 | 12 mi | 0.2 mi | 0 / 0 |
| Sep 18, 1989 | F0 | 15 mi | 0.2 mi | 0 / 0 |
| Sep 18, 1989 | F0 | 15 mi | 0.2 mi | 0 / 0 |
| Mar 29, 1982 | F0 | 11 mi | 0.1 mi | 0 / 0 |
The strongest 10 of 10, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in San Ramon
The Storm Prediction Center has 8 hail reports within 10 miles of San Ramon since 2018, made on 7 separate days. None of them reached 1 inch. The largest size, 0.25 inches, was reported on 7 days, most recently March 15, 2021. The most recent report is from March 15, 2021.
Source: NOAA Storm Prediction Center severe weather reports, data through 2025.
Weather by month in San Ramon
The nearest NOAA station with 1991–2020 climate normals is Livermore, CA, 8 miles southeast of San Ramon at 393 feet. July is the warmest, with an average high of 89°F and low of 57°F; December is the coolest, at 57°F and 39°F. January is the wettest at 2.8 inches of precipitation on average and July and August the driest at 0.0 inches; the year adds up to 14.5 inches over 35 days with at least a tenth of an inch. Highs reach 90°F on about 57 days a year, almost all from May to October. Lows fall below freezing on about 13 nights a year. That 14.5 inches is more than at 100 of the 226 California stations used on this site (44%). Danville, 3 miles north, has its own station (Mt Diablo Junction, CA): 26.1 inches a year, 11.6 more than here, and a July average high of 83°F against 89°F.
Water temperature at the NOAA tide station Alameda, CA, 20 miles west, averaged 69°F in August and 53°F in January over 2021–2025. No month averaged 80°F. Sea level at the Alameda tide gauge, 20 miles from San Ramon, has risen 0.37 ± 0.07 inches per decade from 1939 to 2025, NOAA's linear trend; at that pace it is 3.7 inches in a hundred years. That is faster than at 21 of the 144 U.S. gauges with a NOAA trend.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" | Water °F |
|---|---|---|---|---|---|
| Jan | 57 | 39 | 2.8 | 6 | 53 |
| Feb | 61 | 41 | 2.7 | 7 | 54 |
| Mar | 66 | 43 | 2.2 | 6 | 57 |
| Apr | 71 | 46 | 1.1 | 3 | 61 |
| May | 77 | 50 | 0.5 | 2 | 64 |
| Jun | 84 | 54 | 0.1 | 0 | 67 |
| Jul | 89 | 57 | 0.0 | 0 | 68 |
| Aug | 89 | 57 | 0.0 | 0 | 69 |
| Sep | 86 | 55 | 0.1 | 0 | 69 |
| Oct | 77 | 50 | 0.8 | 2 | 65 |
| Nov | 65 | 43 | 1.5 | 4 | 59 |
| Dec | 57 | 39 | 2.7 | 6 | 54 |
| Year | 73 | 48 | 14.5 | 35 | 62 |
Averages for 1991–2020 at Livermore, CA (393 ft), from NOAA NCEI U.S. Climate Normals; water temperature: average of hourly readings 2021–2025 at the NOAA tide station Alameda, CA, from NOAA Tides & Currents. Normals describe the station; the farther a place is from it, and the bigger the difference in height, the more its weather can differ.
Floods, thunderstorm wind and lightning near San Ramon
Since 1996, the National Weather Service has logged 38 flood, rain, thunderstorm wind and lightning events that began within 10 miles of San Ramon: 33 floods, 2 heavy rain events, 2 thunderstorm wind reports and 1 flash flood. None is recorded as killing or injuring anyone; the NWS estimated $2,540 in property and crop damage. The strongest thunderstorm gust on record here was 63 mph, on August 16, 2020.
Source: NOAA NCEI Storm Events Database, events whose starting point is on record, 1996 to June 30, 2026. Damage is the NWS estimate in the dollars of the year, not insured losses, and NWS notes that some reports are unverified.
Flood insurance claims, disaster declarations and FEMA risk ratings
Flood insurance policyholders in San Ramon's ZIP code 94583 have filed 23 claims with the National Flood Insurance Program since 1982, and were paid $676,000 for buildings and contents, in the dollars of each year. 39% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 415 California cities on this site with 10 or more claims, 112 have fewer than San Ramon.
Contra Costa County, which includes San Ramon, has been named in 21 federal disaster or emergency declarations since 1969, 16 of them major disasters (by incident: 8 floods, 6 severe storms, 2 biological emergencies, 2 coastal storms). The latest major disaster declaration was Severe Winter Storms, Flooding, Landslides, and Mudslides, on January 14, 2023. FEMA's National Risk Index gives Contra Costa County a Very High rating for natural hazard risk overall; by hazard: Very High for inland flooding; Relatively High for lightning and heat waves; Relatively Moderate for coastal flooding; Relatively Low for tornadoes and strong wind; Very Low for hail. It models the county's expected loss from all 18 hazards it covers at $970.5 million a year, the 8th highest of 58 California counties; of the hazards above, the largest share, $412.5 million (42%), is from inland flooding.
Claims: FEMA, OpenFEMA Dataset FIMA NFIP Redacted Claims – v3, summed over ZIP codes; payments in the dollars of each year, not adjusted for inflation. Declarations: Disaster Declarations Summaries – v2, by county. Retrieved October 25, 2026. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Risk ratings: FEMA, National Risk Index county table, December 2025 (v1.20), retrieved October 26, 2026; ratings compare counties nationwide, are meant for planning and are no substitute for a local risk assessment. This product uses the Federal Emergency Management Agency's National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
What counts as a pass, the distances and the sources: how this storm history is built.