NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit Mill Valley, 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 Mill Valley, California since records began in 1851. Since 1950, 4 tornadoes have touched down within 25 miles, 0 of them rated EF3 or stronger.
- Hurricanes
- 0
- Tropical storms
- 0
- Tornadoes
- 4
- 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 Mill Valley
The highest rating among the 4 tornadoes within 25 miles is F1, reached 2 times; the most recent, on March 20, 2005, came within 18 miles. Of the 705 California cities on this site, 83% have more tornadoes within 25 miles than Mill Valley. Hail has been reported within 10 miles 15 times since 1996, with stones up to 1 inch (quarter size). Mill Valley has more hail reports within 10 miles than 95% of the 705 California cities.
Compare Mill Valley's storm record with another city →
Tornadoes within 25 miles of Mill Valley
By decade
- 2000s1
- 1990s2
- 1950s1
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Mar 20, 2005 | F1 | 18 mi | 3 mi | 0 / 0 |
| Apr 1, 1958 | F1 | 22 mi | 0.2 mi | 0 / 0 |
| Dec 5, 1998 | F0 | 11 mi | 1.5 mi | 0 / 0 |
| Dec 17, 1992 | F0 | 24 mi | 0.2 mi | 0 / 0 |
The strongest 4 of 4, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in Mill Valley
The Storm Prediction Center has 15 hail reports within 10 miles of Mill Valley since 1996, made on 14 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 4, 1996. The most recent report is from March 28, 2023. March has the most reports, 8.
Source: NOAA Storm Prediction Center severe weather reports, data through 2025.
Weather by month in Mill Valley
The nearest NOAA station with 1991–2020 climate normals is Kentfield, CA, 4 miles north of Mill Valley at 145 feet. August is the warmest, with an average high of 83°F and low of 54°F; December is the coolest, at 56°F and 42°F. December is the wettest at 9.8 inches of precipitation on average and July the driest at 0.0 inches; the year adds up to 44.5 inches over 50 days with at least a tenth of an inch. Highs reach 90°F on about 27 days a year, almost all from May to October. Lows fall below freezing on about 5 nights a year. That 44.5 inches is more than at 209 of the 226 California stations used on this site (92%). Tiburon, 4 miles east, has its own station (Richmond, CA): 24.5 inches a year, 20.0 less than here, and an August average high of 72°F against 83°F.
Water temperature at the NOAA tide station Richmond, CA, 8 miles east, averaged 66°F in August and September and 53°F in January over 2021–2025. No month averaged 80°F. Sea level at the San Francisco tide gauge, 8 miles from Mill Valley, has risen 0.78 ± 0.03 inches per decade from 1897 to 2025, NOAA's linear trend; at that pace it is 7.8 inches in a hundred years. That is faster than at 37 of the 144 U.S. gauges with a NOAA trend.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" | Water °F |
|---|---|---|---|---|---|
| Jan | 57 | 42 | 8.8 | 9 | 53 |
| Feb | 61 | 43 | 8.7 | 9 | 54 |
| Mar | 65 | 44 | 6.0 | 8 | 55 |
| Apr | 69 | 46 | 2.6 | 4 | 58 |
| May | 74 | 50 | 1.4 | 2 | 60 |
| Jun | 80 | 52 | 0.4 | 1 | 62 |
| Jul | 83 | 53 | 0.0 | 0 | 65 |
| Aug | 83 | 54 | 0.1 | 0 | 66 |
| Sep | 82 | 53 | 0.1 | 0 | 66 |
| Oct | 76 | 50 | 2.0 | 2 | 63 |
| Nov | 64 | 45 | 4.6 | 5 | 59 |
| Dec | 56 | 42 | 9.8 | 9 | 54 |
| Year | 71 | 48 | 44.5 | 50 | 60 |
Averages for 1991–2020 at Kentfield, CA (145 ft), from NOAA NCEI U.S. Climate Normals; water temperature: average of hourly readings 2021–2025 at the NOAA tide station Richmond, 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 Mill Valley
Since 1996, the National Weather Service has logged 88 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Mill Valley: 67 floods, 8 heavy rain events, 6 thunderstorm wind reports, 5 flash floods and 2 lightning strikes. They killed 1 person and injured 0, and the NWS estimated $301,000 in property and crop damage. The strongest thunderstorm gust on record here was 90 mph, on December 25, 2025. Of the 550 California cities on this site with a flash flood on record, 163 have had fewer than Mill Valley.
January 14, 2023: thunderstorm wind 9 miles from the centre of Mill Valley — 1 killed.
October 13, 2009: flood 5 miles from the centre of Mill Valley — $100,000 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 Mill Valley's ZIP code 94941 have filed 388 claims with the National Flood Insurance Program since 1978, and were paid $3.7 million for buildings and contents, in the dollars of each year. The most came from Flooding in 1982: 140 claims (36% of all) and $544,000, then Pineapple Express - Southern in 1998 with 15. 40% 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, 392 have fewer than Mill Valley.
| Event | Claims | Paid |
|---|---|---|
| Flooding1982 | 140 | $544,000 |
| Pineapple Express - Southern1998 | 15 | $38,000 |
Marin County, which includes Mill Valley, has been named in 26 federal disaster or emergency declarations since 1964, 22 of them major disasters (by incident: 10 severe storms, 9 floods, 2 biological emergencies, 1 coastal storm). The latest major disaster declaration was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, on April 3, 2023. FEMA's National Risk Index gives Marin County a Relatively High rating for natural hazard risk overall; by hazard: Very High for coastal flooding; Relatively High for inland flooding; Relatively Low for lightning and heat waves; Very Low for tornadoes, hail and strong wind. It models the county's expected loss from all 18 hazards it covers at $259.3 million a year, the 22nd highest of 58 California counties; of the hazards above, the largest share, $116.0 million (45%), 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.