California, 2018

Flash Flood and Heavy Rain in California, October 2 to 3, 2018

October 2 to 3, 2018 · NWS STO · 8 events in 3 counties and zones

Scattered thunderstorms brought local flooding in a recently burned area. Minor flooding also occurred on roads due to clogged drains.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
$10,000
Crop damage
None recorded
Events
8

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS STO wrote it up.

Scattered thunderstorms brought local flooding in a recently burned area. Minor flooding also occurred on roads due to clogged drains.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sacramento, CA wrote its last area forecast discussion before the first event at Oct 1, 9:59 PM PST, 2 hours 1 minute earlier.

Area forecast discussion, Oct 1, 9:59 PM PST, 2 hours 1 minute before
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The radar

The Sacramento radar (KDAX), 55 km away, was scanning. The volume nearest the first event began at 08:00 UTC.

Open the radar archive at this moment

Event by event

7 heavy rain, 1 flash flood. Local standard time, as filed.

Heavy Rain, Placer

When
October 2, 12:00 AM PST to October 3, 9:00 AM PST
Where
Placer County, Loomis
Reported by
Trained Spotter
Coordinates
38.820, -121.200

There was 1.41 of rain measured over 24 hours by a weather spotter in Loomis.

Heavy Rain, San Joaquin

When
October 2, 4:48 PM PST to October 3, 4:48 PM PST
Where
San Joaquin County, 0.69 mi N of Ripon
Reported by
Law Enforcement
Coordinates
37.740, -121.130

Roadway flooding at 4th St. and Hekman Circle. A vehicle was stalled on a flooded road.

Heavy Rain, San Joaquin

When
October 2, 5:04 PM PST to October 3, 5:04 PM PST
Where
San Joaquin County, 0.69 mi N of Ripon
Reported by
Law Enforcement
Coordinates
37.740, -121.130

A vehicle was stuck in a flooded roadway at West Colony Rd. and Calhoun Ave.

Heavy Rain, San Joaquin

When
October 2, 5:16 PM PST to October 3, 5:16 PM PST
Where
San Joaquin County, 0.69 mi N of Ripon
Reported by
Law Enforcement
Coordinates
37.740, -121.130

Roadway flooding was reported on Doak Blvd and South Mohler Rd and on Grange Way.

Heavy Rain, Placer

When
October 2, 5:58 PM PST to October 3, 5:58 PM PST
Where
Placer County, 0.88 mi SE of Loomis
Reported by
Law Enforcement
Coordinates
38.810, -121.190

Off ramp at Penryn Rd. at I80 was partially blocked due to flooding.

Heavy Rain, San Joaquin

When
October 2, 6:03 PM PST to October 3, 6:03 PM PST
Where
San Joaquin County, Manteca
Reported by
Law Enforcement
Coordinates
37.800, -121.220

All three lanes of Highway 99 and Highway 120 off ramp were flooded.

Heavy Rain, San Joaquin

When
October 2, 6:19 PM PST to October 3, 6:19 PM PST
Where
San Joaquin County, 1.48 mi SSW of Lockeford
Reported by
Law Enforcement
Coordinates
38.150, -121.160

Both lanes on North Sierra Drive were flooded.

Flash Flood, Lake

When
October 3, 8:10 PM PST to 11:00 PM PST
Where
Lake County, 0.92 mi NNW of Summit to 0.9 mi NNW of Summit
Cause
Heavy Rain / Burn Area
Property damage
$10,000
Reported by
Emergency Manager
Coordinates
39.192, -123.037

Emergency Manager relayed a report of a creek beginning to flood a barn near the Mendocino-Lake County border. The water was black from ash in the Mendocino Complex and higher than the resident had ever seen before.

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in California in 2018Every state in 2018This day in weather historyWarnings in California, October 2018

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 789401, 789385, 789395, 789396, 789397, 789399, 789400, 788395.