Rare September storm soaks Westside as Marie's moisture breaks records

Tropical moisture from Hurricane Marie, remaining hundreds of miles offshore, delivered widespread showers and locally heavier downpours across Santa Monica and Los Angeles County on Sunday, September 6. Rain began early in the morning and continued on and off through the afternoon and evening, with isolated thunderstorms in some areas.

National Weather Service forecasts issued Saturday and early Sunday called for generally light amounts-most locations a quarter-inch or less, with isolated totals approaching a half-inch in the foothills. Observed rainfall substantially exceeded those expectations across the Westside and nearby hills. Storm totals through Monday morning included about 1.05 inches at Santa Monica Airport, 1.25 inches in Culver City, 1.42 inches in Beverly Hills, and 1.56 inches in Bel Air. Monte Nido recorded about 1.49–1.53 inches. Downtown Los Angeles finished near 0.73 inches and Los Angeles International Airport near 0.59–0.60 inches. Several foothill and valley sites topped an inch, including Hollywood Reservoir (1.05 inches) and Burbank (about 1.27–1.30 inches).

Flooding Reported in Seal Beach, Long Beach as Tropical Storm Marie Leaves So Cal.

The rain set multiple daily records for September 6, including 0.70 inches downtown (old record 0.17 inches in 1965), 0.59 inches at LAX (old record 0.02 inches in 1965), about 1.3 inches at Hollywood Burbank Airport (old record 0.82 inches in 1976), and 0.68 inches at Long Beach Airport (old record 0.12 inches in 1971). Official climate stations at Downtown Los Angeles and LAX had recorded no measurable precipitation from July 1 through September 5. Sunday's rain marked the first significant wetting in at least two months and the first notable September rainfall of the season after an otherwise dry summer.

The moisture was welcome after the prolonged dry stretch, but it produced slick roads from accumulated oil, scattered crashes, and minor urban flooding. Flood advisories covered parts of Los Angeles County, including recent burn scars (Palisades, Franklin, Summit, and Bridge), with isolated debris-flow and small-stream concerns. Power outages hit Arcadia, including traffic signals and a police station. A tree was reported down on vehicles in at least one incident. Coastal flooding was more notable than inland flooding: seawater overtopped walls and flooded streets and low-lying homes in Long Beach, while parking lots at Seal Beach and Zuma Beach inundated. Waves of 6 to 10 feet prompted rescues and beach closures.

Labor Day Monday turned much drier and sunnier after leftover showers early. Highs near the coast reached the upper 70s to around 80 degrees under partly cloudy to sunny skies. Little additional accumulation was anticipated.

High surf and coastal flood advisories remain in effect through Tuesday evening for Los Angeles County beaches, including Santa Monica, due to elevated south swells from the distant storm. An ocean water-quality advisory advises against swimming for 72 hours after rainfall. Beachgoers should use caution with rip currents and stay off rocks and jetties. Conditions are expected to improve midweek as the tropical moisture recedes.

Warmer and mostly dry weather is expected to return to Santa Monica after Sunday's rain. National Weather Service forecasts for the beaches show:

Monday (Labor Day): sunny, high near 80°F

Tuesday: mostly sunny, high near 83°F

Wednesday: sunny, high near 86°F

Thursday: sunny, high near 81°F

Friday: sunny, high near 79°F

Other forecasts cluster in a similar range, with Monday highs around 80–85°F and midweek peaks in the mid-80s before a slight cooldown toward the weekend. Inland areas will run several degrees warmer. No significant rain is expected through the week.