Las Vegas Storm History, the Floods That Hit the Valley
Las Vegas gets about four inches of rain in a normal year, yet the valley has a long record of storms that dropped a big share of that in an afternoon. Here is the record, day by day, and what it means for the houses inside 4 miles of downtown.
How storms hit the Las Vegas Valley
The National Weather Service office in Las Vegas says monsoon moisture usually pushes into the Mojave Desert in July and August. Storms build over the mountains around the valley and then drift into it. Flash floods often sweep down washes that sit dry the rest of the year, or pour into low lying streets. By September the monsoon usually fades.
The Clark County Regional Flood Control District puts it plainly. July through September bring sudden downpours and fast flash flooding, even on sunny days. The ground does not help. NWS explains that caliche, the hard layer under much of the valley, is almost impervious, so when rain falls nearly all of it runs off.
That is why a city with 3.99 inches of rain in a normal year, per NOAA normals for the airport, still floods. NOAA counts only about 2.3 days a year with half an inch of rain or more. When one of those days lands as a single storm cell over your street, the water has nowhere to go but downhill.
From the NWS Las Vegas climate page, the Regional Flood Control District flash flood safety page, the NWS Nevada flood page and NOAA 1991 to 2020 normals.
The wettest days on record
The NOAA daily record for the Las Vegas area runs back to January 1937. We pulled every day of it, more than 32,000 of them, and sorted by rain. The chart below shows the seven wettest days, the 1999 flood day and the storm from earlier this month.
Wettest days at the Las Vegas airport, NOAA record back to 1937
The top day, August 21, 1957, dropped 2.58 inches at the airport. That is about 65% of a normal year in one day. Only 30 days in the whole record reached an inch or more, and 16 of those 30 fell in July, August or September. The summer storms are rare, but they are the big ones.
Daily totals from the NOAA Regional Climate Centers ACIS record for the Las Vegas area, the same data the NWS NOWData tool shows. Pulled October 31, 2026, through October 29, 2026.
Storms worth remembering
- August 21, 1957. 2.58 inches at the airport, still the wettest day in the record.Source NOAA ACIS daily record
- 1984. FEMA says El Nino storms hit the Las Vegas area that year and seven people died. July 28, 1984 brought 1.36 inches, still the wettest July day at the airport.Source fema.gov
- July 8, 1999. Most of the rain fell in about 90 minutes, from 10:30 a.m. to noon, with 1.5 to 3 inches over much of the valley. Two people died, a motorist and a man caught in Flamingo Wash. NWS counts 369 homes damaged or destroyed and more than 200 swift water rescues. A federal disaster was declared July 19.Source weather.gov
- August 22, 2012. 1.65 inches at the airport, the second wettest day in the record.Source NOAA ACIS daily record
- September 11, 2012. 1.18 inches, the wettest September day on record. NWS says the 1999 flood tied this one as the worst flood in modern Las Vegas.Source weather.gov
- July 28, 2022. The airport caught only 0.32 inches while some pockets got over an inch. Downtown intersections flooded, casino roofs leaked, and Las Vegas Fire and Rescue answered 330 calls with seven swift water rescues.Source spokesman.com
- August 20, 2023. Tropical Storm Hilary reached the valley. The airport logged 0.34 inches that day. The Review Journal reported nearly 8 inches at Lee Canyon on Mount Charleston during the storm. August 2023 ended at 1.17 inches and September 2023 at 1.51.Source reviewjournal.com and NOAA ACIS
- October 10, 2025. 0.92 inches at the airport. The Review Journal reported two people rescued and one missing after rain deluged a wash near the Strip.Source reviewjournal.com
- October 11, 2026. 1.08 inches at the airport, tying October 12, 1947 for the wettest October day in the record. October 2026 had 1.19 inches by October 29, more than three times the 0.35 inch normal.Source NOAA ACIS daily record
- October 30, 2026. NWS Las Vegas issued a flash flood warning from 12:55 to 4 p.m. for Las Vegas, North Las Vegas, Fremont Street, East Las Vegas and the Strip, with radar showing up to an inch of rain already down. At 1:04 p.m. a severe thunderstorm warning followed for a storm over Fremont Street with quarter size hail and gusts up to 50 mph.Source NWS flash flood warning and NWS severe thunderstorm warning
Washes, channels and detention basins
After the floods of the 1970s and early 1980s, the Nevada Legislature authorized flood control districts in 1985, and Clark County voters funded the Regional Flood Control District the next year. The district says it now runs 113 detention basins and more than 722 miles of channels and underground storm drains, with about 75% of its master plan built.
Those channels are the dry concrete washes you drive over every day. When a storm hits, the district warns that water in a flood channel can move at 30 mph, six inches of moving water can knock a person off their feet, and one foot of water can float most cars. Stay out of them, and keep kids out of them, even after the rain stops.
Some of our neighborhoods sit right on that history. In 1999 debris backed up Flamingo Wash in the east valley and water flooded Boulder Highway, which is why East Las Vegas and Winchester pages talk about it.
From the Regional Flood Control District story page and its flash flood safety page.
What the record means for your house
Three lessons come out of 89 years of storm days.
- Storms are local. In July 2022 the airport saw a third of an inch while downtown streets flooded. A dry airport reading does not mean your block stayed dry.
- Storm water that came across the ground is Category 3 water. It carries soil, oil and bacteria, so carpet, pad and the bottom of the drywall it soaked usually come out. See flood cleanup and water extraction.
- Hail and wind open roofs. The October 30 storm carried quarter size hail over Fremont Street. Water that gets in up top shows up later as a stain or a sagging ceiling. See ceiling and roof leaks.
Insurance follows the same split. Triple I says standard home, condo and renters policies exclude flood, so water that rose from the ground is a different claim from water that came through storm damage to the roof. The claim help page covers the records an adjuster will want.
Watching the next storm
Our Las Vegas storm tracker pulls live alerts and the forecast from the National Weather Service. When a warning has an outline on the map, the tracker checks it against every neighborhood we cover and lists the ones inside it, with the help that fits that kind of storm.
Questions people ask
What is the wettest day on record in Las Vegas?
When is monsoon season in Las Vegas?
What was the worst flood in modern Las Vegas?
Did it really rain that much in October 2026?
Why does Las Vegas flood with so little rain?
Where can I see live Las Vegas storm alerts?
Service area
Serving Central Las Vegas and Nearby
Inside 4 miles of downtown Las Vegas
Water where it should not be?
Storm water inside? Call or text. Say where it came in, when, and which rooms are wet, and you will get the first steps right away.