NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit Discovery Bay, 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 Discovery Bay, California since records began in 1851. Since 1950, 20 tornadoes have touched down within 25 miles, 0 of them rated EF3 or stronger.
- Hurricanes
- 0
- Tropical storms
- 0
- Tornadoes
- 20
- 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 Discovery Bay
The highest rating among the 20 tornadoes within 25 miles is F1 or EF1, reached 2 times; the most recent, on January 23, 2010, came within 6 miles. Of the 20, none had a path within 5 miles of the city centre, and 5 have come since 2000. April has had the most tornadoes, 8. The most recent tornado was on April 21, 2022. Discovery Bay has more tornadoes within 25 miles than 64% of the 705 California cities on this site. Hail has been reported within 10 miles 3 times since 1983, with stones up to 1 inch (quarter size). Of the 705 California cities, 44% have more hail reports within 10 miles than Discovery Bay.
Compare Discovery Bay's storm record with another city →
Tornadoes within 25 miles of Discovery Bay
By decade
- 2020s1
- 2010s2
- 2000s2
- 1990s6
- 1980s5
- 1970s2
- 1960s2
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Jan 23, 2010 | EF1 | 6 mi | 1.64 mi | 0 / 0 |
| May 31, 1967 | F1 | 20 mi | 0.1 mi | 0 / 0 |
| Apr 11, 2012 | EF0 | 17 mi | 0.25 mi | 0 / 0 |
| Dec 26, 2005 | F0 | 14 mi | 0.3 mi | 0 / 0 |
| Apr 8, 2005 | F0 | 19 mi | 1.5 mi | 0 / 0 |
| Mar 28, 1998 | F0 | 21 mi | 0.1 mi | 0 / 0 |
| Feb 19, 1998 | F0 | 6 mi | 0.2 mi | 0 / 0 |
| Apr 1, 1996 | F0 | 24 mi | 0.3 mi | 0 / 0 |
| Apr 1, 1996 | F0 | 19 mi | 0.8 mi | 0 / 0 |
| Apr 25, 1994 | F0 | 14 mi | 0.7 mi | 0 / 0 |
| Mar 26, 1991 | F0 | 24 mi | 0.1 mi | 0 / 0 |
| Sep 18, 1989 | F0 | 23 mi | 0.2 mi | 0 / 0 |
The strongest 12 of 20, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in Discovery Bay
The Storm Prediction Center has 3 hail reports within 10 miles of Discovery Bay since 1983, made on 2 separate days. Of these, one was 1 inch across or larger, and none reached 2 inches. The largest, 1 inch (quarter size), fell on March 31, 2013, the most recent report.
Source: NOAA Storm Prediction Center severe weather reports, data through 2025.
Weather by month in Discovery Bay
The nearest NOAA station with 1991–2020 climate normals is Tracy Pumping Plt, CA, 5 miles southeast of Discovery Bay at 61 feet. July is the warmest, with an average high of 93°F and low of 62°F; January is the coolest, at 56°F and 41°F. January is the wettest at 2.5 inches of precipitation on average and July and August the driest at 0.0 inches; the year adds up to 12.3 inches over 31 days with at least a tenth of an inch. Highs reach 90°F on about 82 days a year, almost all from April to October. Lows fall below freezing on about 10 nights a year. That 12.3 inches is more than at 69 of the 226 California stations used on this site (31%). Brentwood, 6 miles northwest, has its own station (Antioch Pumping Plt #3, CA): 12.7 inches a year, 0.4 more than here, and a July average high of 91°F against 93°F.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" |
|---|---|---|---|---|
| Jan | 56 | 41 | 2.5 | 6 |
| Feb | 62 | 44 | 2.3 | 6 |
| Mar | 67 | 47 | 1.6 | 5 |
| Apr | 73 | 50 | 0.8 | 3 |
| May | 80 | 55 | 0.5 | 1 |
| Jun | 88 | 59 | 0.1 | 0 |
| Jul | 93 | 62 | 0.0 | 0 |
| Aug | 93 | 62 | 0.0 | 0 |
| Sep | 89 | 60 | 0.1 | 0 |
| Oct | 79 | 55 | 0.7 | 1 |
| Nov | 66 | 46 | 1.3 | 3 |
| Dec | 57 | 40 | 2.4 | 6 |
| Year | 75 | 52 | 12.3 | 31 |
Averages for 1991–2020 at Tracy Pumping Plt, CA (61 ft), from NOAA NCEI U.S. Climate Normals. 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 Discovery Bay
Since 1996, the National Weather Service has logged 6 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Discovery Bay: 6 floods. None is recorded as killing or injuring anyone; the NWS estimated $44.0 million in property and crop damage.
December 31, 2005: flood 4 miles from the centre of Discovery Bay — $22.0 million damage.
January 1, 2006: flood 4 miles from the centre of Discovery Bay — $22.0 million damage.
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 Discovery Bay's ZIP code 94505 have filed 21 claims with the National Flood Insurance Program since 1980, and were paid $160,000 for buildings and contents, in the dollars of each year. 71% 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, 95 have fewer than Discovery Bay.
Contra Costa County, which includes Discovery Bay, 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.