Union City, CA Tornado History — 12 Tornadoes Since 1950
How many tornadoes has Union City, CA had?
Union City has had 12 tornadoes on record within 25 miles since 1950.
When was the most recent tornado near Union City?
The most recent tornado within 25 miles of Union City was a F1 on March 20, 2005.
When is tornado season in Union City?
January is historically the peak month for tornadoes near Union City, with 2 on record. Spring through early summer (April–June) generally sees the highest activity across most of the central and southern United States.
At a Glance
Tornadoes by Decade
Tornadoes by Enhanced Fujita Rating
F0–F5 ratings (pre-2007) are grouped with their EF equivalents. The Enhanced Fujita scale replaced the original Fujita scale in February 2007.
Tornadoes by Month
Have any tornadoes near Union City been fatal?
No fatalities are on record within 25 miles of Union City from any of the 12 tornadoes since 1950, though 3 injuries have been reported. NOAA Storm Prediction Center records.
Notable Tornadoes Near Union City
About Tornadoes in Union City
This overview was written April 23, 2026. The tornado counts and notable-event figures elsewhere on this page reflect the latest data and may differ from this summary.
Union City, California, situated in the San Francisco Bay Area, has experienced 12 documented tornadoes within a 25-mile radius since 1950, according to the NOAA Storm Prediction Center. This relatively modest total reflects the region's distance from the nation's most tornado-prone areas, though the Bay Area is not immune to these atmospheric phenomena. The distribution across decades shows considerable variation, with the 1990s accounting for more than half of all recorded events at seven tornadoes, while the 1950s and 1980s each saw two, and the 2000s recorded just one.
The intensity of tornadoes near Union City has remained on the lower end of the Enhanced Fujita scale. Six events were rated EF0, representing the weakest category with wind speeds between 65 and 85 mph. Four tornadoes reached EF1 intensity, with winds from 86 to 110 mph, while only two achieved EF2 status, featuring winds of 111 to 135 mph. Notably, no tornadoes on record in this area have resulted in fatalities, distinguishing the region from areas where tornadoes more frequently produce casualties.
January emerges as the peak month for tornado activity near Union City, with two recorded events, an unusual pattern compared to the spring and early summer peak typical of the central United States. The costliest and longest-tracked tornado occurred on January 11, 1951, when an F2 tornado carved a 5.7-mile path with a maximum width of just 10 yards, causing $2.75 million in property damage. The widest tornado on record struck on May 6, 1998, reaching 100 yards across during its 0.6-mile track, though it caused minimal monetary damage.
The most recent tornado in the area touched down on March 20, 2005, rated F1 with a 3.0-mile path length and maximum width of 30 yards. Like all tornadoes documented near Union City, this event produced no fatalities. The Enhanced Fujita scale, implemented in 2007 to replace the original Fujita scale, provides standardized damage indicators to estimate wind speeds and assign ratings from EF0 through EF5, though no tornado above EF2 intensity has been recorded in this coastal California region.