Photo: Sanfranman59 · CC BY-SA 3.0On FEMA’s figures, Palo Alto faces more hazard damage per building than 96% of U.S. towns, mostly from earthquakes
On FEMA’s National Risk Index, Palo Alto gets a D− for hazard risk: higher expected damage per building than 96% of U.S. towns, #651 of 847 in California. Most of that expected damage is earthquakes (52%), then river and rain flooding (47%). Flood insurance has paid 376 claims here since 1980.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What stands out about Palo Alto’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Palo Alto faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
Earthquakes
River and rain flooding
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
What’s behind Palo Alto’s grade
Earthquakes are 52% of the building damage FEMA expects in Palo Alto, and Palo Alto’s rate of earthquakes damage is in the top 3% of U.S. census tracts. River and rain flooding adds 47%, at a rate in the top 6% of U.S. census tracts.
D− #651 of 847 in California; higher expected damage per building than 96% of U.S. towns (21,298).
Palo Alto’s residents live in 22 census tracts; FEMA’s figures are combined by where they live.
The typical California town has higher expected damage than 92% of U.S. towns; within the state, Palo Alto has more expected damage per building than 77% of California towns.
In dollars, FEMA expects about $103M a year in losses across Palo Alto: $81.6M to buildings, the rest to people and crops.
Does Palo Alto flood? Yes: 376 flood claims since 1980
Every paid claim on a federal flood insurance policy in Palo Alto, from FEMA’s records: 12.9 per 1,000 homes, more than 78% of the 13,809 U.S. towns with a flood insurance record.
- The Pineapple Express - Southern339 claims · $8.4M
- The California Atmospheric River7 claims · $435K
Palo Alto is in FEMA’s Community Rating System (class 6) for its flood-proofing work.
Insurance rates: Santa Clara County.2 federal disasters brought FEMA money to Palo Alto
Disasters that paid out in Palo Alto itself (aid to households or repair grants to the City of Palo Alto), newest first, with that year’s flood claims.
- 2023Severe Winter Storms, Straight-line Winds, Flooding, Landslides, and Mudslides$387K to the City of Palo Alto for repairs
- 2022Severe Winter Storms, Flooding, Landslides, and Mudslides25 households applied for aid$40K aid approved$863K to the City of Palo Alto for repairs7 flood claims paid that year
Santa Clara County has had 19 natural disasters declared by the President since 1953, most often severe storms, then floods. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Also 3 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in Santa Clara County, 2002–2020.
Old photos of Palo Alto after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Palo Alto archive →Palo Alto and its neighbors
Palo Alto is 8th of the 8 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Stanford | Dmore damage than 87% | earthquakes | 1 |
| Los Altos Hills | Dmore damage than 88% | earthquakes | 6 |
| Mountain View | Dmore damage than 92% | earthquakes | 5 |
| East Palo Alto | Dmore damage than 93% | earthquakes | 23 |
| Menlo Park | Dmore damage than 94% | earthquakes | 16 |
| Portola Valley | Dmore damage than 95% | earthquakes | 12 |
| Los Altos | Dmore damage than 95% | river and rain flooding | 4 |
| Palo Alto | D−more damage than 96% | earthquakes | 376 |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what Palo Alto faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
- Palo Alto residents get 20% off flood insurance.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Palo Alto
Is Palo Alto at risk for natural disasters?
On FEMA’s National Risk Index, Palo Alto has higher expected damage per building than 96% of U.S. towns: D− for hazard risk, #651 of 847 in California. Most of the expected damage is earthquakes (52%) and river and rain flooding (47%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Palo Alto flood?
Flood insurance has paid 376 claims in Palo Alto since 1980, $9.4M in all, or 12.9 per 1,000 homes, more than 78% of U.S. towns with a flood insurance record. 6 properties have flooded more than once. The most claims came from Pineapple Express - Southern (339).
Is Palo Alto in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Santa Clara County, 22% of homes in mapped flood zones carry federal flood insurance, and 1.7% of all homes do.
How much is flood insurance in Palo Alto?
Palo Alto is in FEMA’s Community Rating System (class 6), which takes 20% off federal flood insurance policies for its flood-proofing work. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Palo Alto?
By FEMA money that reached Palo Alto, Severe Winter Storms, Flooding, Landslides, and Mudslides (2022): 25 households applied for aid, $40K approved, and $863K to the City of Palo Alto for repairs. By flood claims, Pineapple Express - Southern: 339 paid, $8.4M.
Is Palo Alto at risk from earthquakes?
It is the largest share of the building damage FEMA expects here (52%), and Palo Alto’s rate for it is in the top 3% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Palo Alto.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Palo Alto’s residents lived in the 2020 census; OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.