Severe Weather History


County archive · 1950 — present

Alameda County, California

Alameda County, California severe weather history spans 241 recorded events between 1964 and 2026. The dominant hazard is flood, accounting for 63.1% of all recorded events. It ranks #2,170 nationally and #17 in California.

241

Recorded events

2

Direct deaths

2

Direct injuries

$25.5M

Property damage

The record

What the Alameda County, California severe weather history record shows

Across the archive, Alameda County, California severe weather history averages 3.9 recorded events a year. The busiest stretch on record is the 2010s, with 114 events logged in that decade alone. Roughly 5 events fall before 1990 and 236 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.

The deadliest hazard in the Alameda County, California record is flood, responsible for 1 direct deaths. The costliest is flood, with $17.6M in reported property damage. In total, 8 distinct hazard types appear in this county archive, each listed with its own dated record below.

Alameda County, California severe weather history: recorded events per decade since 1950
Alameda County, California severe weather history: recorded events per decade since 1950

By hazard type

Every hazard type recorded in Alameda County

HazardEventsDeathsDamageMaxSpan
Flood1521$17.6M02002–2026
Flash Flood270$701K01996–2025
Hail200$5.0M0.751999–2024
Debris Flow150$1K02012–2023
Heavy Rain151$2.1M01996–2024
Thunderstorm Wind70$10K621964–2024
Tornado30$75KF01982–1994
Lightning20$3K02011–2020
Source: NOAA/NCEI Storm Events · dates UTC · preliminary data may revise

Decade by decade

Alameda County, California severe weather history by decade

11960s
11970s
31980s
261990s
92000s
1142010s
872020s

Reporting practice changed over time — early decades are undercounted, not calmer.

Tornado tracks

Paths crossing this county

4 mapped tornado paths intersect this county: 4 touched down inside it and 0 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.

DateScaleDeathsInjuriesPath lengthOrigin
1980-01-14EF1010.3 miTouched down here
1994-04-25EF0000.7 miTouched down here
1992-12-17EF0000.2 miTouched down here
1982-03-29EF0000.1 miTouched down here
Source: NOAA SPC SVRGIS tornado tracks · path geometry intersected with county boundaries

Significant events

Deadliest events on record in Alameda County

DateTypeLocationDeathsInjuriesDamage
Mar 10, 2023FloodELMHURST11$0
Jan 11, 1998Heavy RainHAYWARD10$0
Mar 10, 2023Heavy RainELMHURST01$0
Source: NOAA/NCEI Storm Events · dates UTC

From the record

What the reports say

Written by National Weather Service staff at the time of the event · public domain

Context

Risk, population and federal disasters

Very High

FEMA NRI risk rating

1,649,473

Population (ACS)

$1.1M

Median home value

24

Federal declarations

DeclaredIncidentTitleType
Apr 3, 2023Severe StormSEVERE WINTER STORMS, STRAIGHT-LINE WINDS, FLOODING, LANDSLIDES, AND MUDSLIDESDR
Jan 14, 2023FloodSEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDESDR
Jan 9, 2023FloodSEVERE WINTER STORMS, FLOODING, AND MUDSLIDESEM
Mar 22, 2020BiologicalCOVID-19 PANDEMICDR
Mar 13, 2020BiologicalCOVID-19EM
Apr 1, 2017FloodSEVERE WINTER STORMS, FLOODING, AND MUDSLIDESDR
Source: FEMA OpenFEMA disaster declarations · most recent first

Within the county

Most affected places

  • Emeryville 143

Quick answers

Frequently asked

How many severe weather events have been recorded in Alameda County, California?

241 events are on record between 1964 and 2026, causing 2 direct deaths and $25.5M in property damage.

What is the most common severe weather hazard in Alameda County?

Flood, with 152 recorded events — 63.1% of everything in the archive for this county.

How many tornadoes have crossed Alameda County?

4 mapped tornado paths intersect the county boundary; 4 of them touched down inside it. This is derived from path geometry, not county-tagged reports.

How many federal disaster declarations cover Alameda County?

24 federal disaster declarations from FEMA include Alameda County, each tied to a specific incident period.

How risky is Alameda County compared with the rest of the country?

FEMA's National Risk Index rates Alameda County as very high risk, placing it in the 100 percentile of its state for expected annual loss.

Where does the Alameda County, California severe weather history data come from?

Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.

Nearby

Neighbouring counties

All counties in this state →

Cite this page

“Alameda County, California.” Severe Weather History. severeweatherhistory.com/county/california/alameda-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.


Historical reference only — for official alerts visit weather.gov