103 flood insurance claims·$560,324 paid·5 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Imperial County, California. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
Flash flooding from thunderstorms dominates the flood risk in Imperial County, California, accounting for 102 events and 2 deaths over the last 30 years alongside 16 standard flood events.
Recent weather events illustrate this hazard. On June 3, 2025, low pressure from the eastern Pacific combined with abundant low-level moisture to produce heavy rainfall exceeding one inch in under an hour along Fish Creek Wash in west-central Imperial County, resulting in flash flooding. Later that year on August 25, 2025, a moist and unstable environment fueled by a subtropical ridge and Pacific trough produced conditions primed for strong thunderstorms with precipitable water values climbing to 1.8 to 2.0 inches.
Homeowners and real estate agents should pay the most attention to properties in unmapped or poorly defined areas, as the National Flood Insurance Program data shows the highest claim volume in Zone UNKNOWN with 63 claims averaging an $8,325 payout and an average recorded water depth of 3 inches. Properties in Zone A also require close attention, accounting for 31 claims with an average payout of $8,859 and an average water depth of 2 inches.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
21% of Imperial County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
39 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 2 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 1983, with 25 claims and $165,240 paid, the year of Flooding.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
104 NOAA storm reports from Imperial County describe what happened, in the words of the forecasters who covered it. Read the California flood stories →
15 federal disaster declarations since 1976, 5 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Tropical Storm Hilary | Aug 19, 2023 |
| Severe Winter Storms, Flooding, Landslides, And Mudslides | Mar 9, 2023 |
| Severe Winter Storms, Straight-line Winds, Flooding, Landslides, And Mudslides | Feb 21, 2023 |
| Earthquake | Apr 4, 2010 |
| Severe Winter Storms, Flooding, And Debris And Mud Flows | Jan 17, 2010 |
| Severe Freeze | Jan 11, 2007 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Winter Storms, Flooding Landslides, Mud Flow | Feb 13, 1995 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
118 since 1996: 102 flash floods and 16 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Sep 27, 2025 | — |
| Flash Flood | Sep 27, 2025 | $20,000 |
| Flash Flood | Aug 25, 2025 | — |
| Flash Flood | Aug 25, 2025 | $2.5M |
| Flash Flood | Sep 22, 2025 | — |
| Flash Flood | Sep 18, 2025 | $30,000 |
| Flash Flood | Sep 18, 2025 | — |
| Flash Flood | Jun 3, 2025 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · Sep 27, 2025. An upper-level low situated over southern CA provided strong upper-level forcing for ascent across the area. Cold 500 mb temperatures of -12 to -13 degrees Celsius and steep lapse rates led to moderate instability values with MLCAPE peaking close to 1000 J/kg. The combination of the upper-level forcing and moderate instability led to the development of strong thunderstorms across the southeastern portion of Imperi…
Flash Flood · Aug 25, 2025. The environment across southeast California on August 25th was primed for strong to severe thunderstorms with very moist and unstable conditions in place. The synoptic pattern featured a subtropical ridge of high pressure centered over northern New Mexico, while a Pacific trough to the west promoted upper level divergence over the region. These synoptic features also allowed for southerly moisture advection with P…
Flash Flood · Sep 22, 2025. Upper-level divergence from an Upper-level trough off the southern CA coast led to the development of a southwest to northeast oriented rain band across the eastern half of Imperial County. Although rainfall intensity for the most part was light to moderate, precipitable water values ranging between 1.5-1.8 supported pockets of heavier rainfall rates with areas across southeastern Imperial County observing total…
Flash Flood · Sep 18, 2025. The combination of an upper-level low off the CA coast and the remnants of Tropical Cyclone Mario resulted in a significant moisture increase with PWATs rising to 1.5 on the 17th and upwards of 1.8-2.0 on the 18th. Thunderstorms on the 17th were concentrated mainly across the higher terrain areas of southeast CA, mainly across the Chocolate Mountains, while on the 18th, the activity was more widespread as upper-le…
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Imperial County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.