Flash Flooding and Flooding in California, October 29, 2007

Name: Flash Flooding and Flooding in California, October 29, 2007
Start: 2007-10-29T15:45
End: 2007-10-29T22:00
Location: California

October 29, 2007 · NWS HNX · 28 events in 7 counties and zones

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: $1.1 million
Crop damage: None recorded
Events: 28

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 HNX wrote it up.

An upper-level low developed off Point Conception by October 27, and slowly drifted northeast toward the central California coast. The low pulled a moist, tropical airmass, including remnants from former Tropical Storm Kiko, into the central California interior on the 29th. A dry air flow became trapped in the area around the storm, clearing skies over the San Joaquin Valley during the late morning, allowing for extensive heating of an already unstable airmass. Then, in the late afternoon, a weather disturbance moved over the southern half of the San Joaquin Valley.

This combination of weather patterns triggered the worst severe thunderstorm outbreak over the central California interior in recent memory, with 15 Severe Thunderstorm Warnings, two Urban and Small Stream Flood Advisories, and a Flash Flood Warning issued between 4 PM and 8 PM. Another Severe Thunderstorm Warning had been issued earlier in the day, at 1:16 PM PDT, for the Sierra foothills in Madera and Mariposa counties. Hail up to an inch in diameter was reported, and flooding occurred in parts of the San Joaquin Valley, including sections of northwest Fresno and downtown Visalia.

Thunderstorm activity continued into the early morning hours of October 30, as a cold front moved through central California. A strong push of cold air into the region dropped the high temperature at Fresno from 80 on the 29th to 68 on the 30th. Bakersfield saw even stronger cooling, from 84 on October 29th to 63 the next day, a 21-degree cooling.

Severe thunderstorms caused several reports of downed power lines and trees, large hail, and flash flooding throughout portions of the San Joaquin Valley.

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 Hanford, CA wrote its last area forecast discussion before the first event at Oct 29, 1:56 PM PST, 1 hour 49 minutes earlier.

Area forecast discussion, Oct 29, 1:56 PM PST, 1 hour 49 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
256 PM PDT MON OCT 29 2007

COORECTED TIME FOR SEVERE THUNDERSTORM WARNING

.DISCUSSION...
KHNX RADAR SHOWING THUNDERSTORMS DEVELOPING OVER THE NORTHEASTERN
QUADRANT OF THE HANFORD WARNING/FORECAST AREA. A FEW STORMS HAVE
EXCEEDED 60 DBZ...WITH VILS OVER 30. A SEVERE THUNDERSTORM WARNING
WAS ISSUED ON THESE STORMS AT 2016Z...BUT HAVE NOT RECEIVED ANY
REPORTS OF LARGE HAIL AT THIS TIME.

THE UPPER-LEVEL LOW CONTINUES TO LIFT NORTHEAST TOWARD THE
COAST...AND SHOWERS AND ISOLATED THUNDERSTORMS HAVE DEVELOPED ALONG
THE CENTRAL CALIFORNIA COAST. AS THE LOW CONTINUES MOVING...THESE
SHOWERS AND THUNDERSTORMS WILL SWING OVER THE COASTAL RANGE AND INTO
THE CENTRAL CALIFORNIA INTERIOR. HAVE GONE WITH SCATTERED
THUNDERSTORMS OVER THE SOUTHERN SIERRA NEVADA THIS EVENING...AND
ISOLATED THUNDERSTORMS ELSEWHERE ACROSS THE HANFORD WARNING/FORECAST
AREA.

A SHORT-WAVE TROUGH IS FORECAST TO DROP OUT OF THE GULF OF ALASKA
TUESDAY...KEEPING A SLIGHT CHANCE OF SHOWERS OVER THE SOUTHERN
SIERRA NEVADA. AS THE TROUGH AXIS MOVES ACROSS THE NORTHERN HALF OF
THE REGION TUESDAY EVENING...COULD SEE A FEW THUNDERSTORMS SPREAD
INTO THE FOOTHILLS...SO HAVE ADDED 20 PERCENT POPS TO THE FOOTHILLS.

BEHIND THIS SHORT-WAVE TROUGH...AN UPPER-LEVEL RIDGE BUILDS OVER THE
EASTERN PACIFIC AND INTO CALIFORNIA THROUGH THE WEEKEND. THIS WILL
KEEP A DRY PATTERN OVER THE HANFORD WARNING/FORECAST AREA WEDNESDAY
THROUGH MONDAY.

NOTE...DAYLIGHT SAVINGS TIME ENDS AT 0200 PDT /0900Z OR 0100 PST/
       SUNDAY MORNING NOVEMBER 4TH.

&&

.AVIATION...
AREAS OF MVFR WITH LOCAL IFR VISIBILITIES AND CEILING THE PRECIP
AND CLOUDS WILL PREVAIL OVER THE HIGHER ELEVATIONS UNTIL 05Z
TUESDAY. OVER THE CENTRAL CAL VALLEY AND KERN DESERTS...VFR WITH
OCCASIONAL MVFR CONDITIONS WILL PREVAIL AS BRIEF RAIN SHOWERS AND
ISOLATED THUNDERSTORMS DEVELOP DURING THE LATE AFTERNOON AND EARLY
EVENING. CONDITIONS WILL CLEAR OVERNIGHT WITH AREAS OF FOG IN THE
VALLEY AND STRATUS ALONG THE FOOTHILLS DEVELOPING BY EARLY TUESDAY
MORNING.

&&

.AIR QUALITY ISSUES...
NONE.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

SANGER/MOLINA

WEATHER.GOV/HANFORD

Hazardous weather outlook, Oct 29, 4:37 AM PST, 11 hours 8 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
537 AM PDT MON OCT 29 2007

CAZ089>095-098-099-301245-
WEST CENTRAL SAN JOAQUIN VALLEY-EAST CENTRAL SAN JOAQUIN VALLEY-
SOUTHWESTERN SAN JOAQUIN VALLEY-SOUTHEASTERN SAN JOAQUIN VALLEY-
MARIPOSA MADERA AND FRESNO COUNTY FOOTHILLS-
TULARE COUNTY FOOTHILLS-KERN COUNTY MOUNTAINS-INDIAN WELLS VALLEY-
SOUTHEASTERN KERN COUNTY DESERT-
537 AM PDT MON OCT 29 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE CENTRAL CALIFORNIA
INTERIOR

.DAY ONE...TODAY AND TONIGHT

A FEW THUNDERSTORMS WILL DEVELOP ACROSS THE SAN JOAQUIN VALLEY...
THE ADJACENT SOUTHERN SIERRA NEVADA FOOTHILLS...AS WELL AS
THE KERN COUNTY MOUNTAINS AND DESERTS THIS AFTERNOON AND EVENING.
DANGEROUS CLOUD TO GROUND LIGHTNING...SMALL HAIL AND LOCALLY
GUSTY WINDS ARE POSSIBLE WITH THE THUNDERSTORMS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS TO THE SAN JOAQUIN VALLEY NATIONAL WEATHER SERVICE
OFFICE.

BINGHAM

WEATHER.GOV/HANFORD

The radar

The Los Angeles radar (KVTX), 85 km away, was scanning. The volume nearest the first event began at 23:42 UTC.

Open the radar archive at this moment

Event by event

11 hail, 11 thunderstorm wind, 3 flash flood, 3 flood. Local standard time, as filed.

Hail, Kern

When: October 29, 3:45 PM PST to 3:47 PM PST
Where: Kern County, 0.89 mi SE of Ford City
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 35.140, -119.460

A trained spotter reported penny sized hail.

Hail, Kern

When: October 29, 3:48 PM PST to 3:50 PM PST
Where: Kern County, 0.89 mi SW of Kern City
Measured: 0.75 in hail
Reported by: Broadcast Media
Coordinates: 35.340, -119.030

TV meteorologist reported penny sized hail.

Hail, Fresno

When: October 29, 4:22 PM PST to 4:25 PM PST
Where: Fresno County, Firebaugh
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 36.850, -120.450

A trained spotter reported penny sized hail.

Hail, Fresno

When: October 29, 4:29 PM PST to 4:31 PM PST
Where: Fresno County, Firebaugh
Measured: 0.75 in hail
Reported by: Newspaper
Coordinates: 36.850, -120.450

A newspaper journalist reported hail at least penny sized.

Hail, Kings

When: October 29, 4:41 PM PST to 4:45 PM PST
Where: Kings County, 0.56 mi W of Cimarron
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 36.300, -119.790

A trained spotter reported penny sized hail at Highway 41 near Mount Whitney Avenue.

Flash Flood, Fresno

When: October 29, 4:44 PM PST to 7:00 PM PST
Where: Fresno County, 0.55 mi E of Kerman to 11.91 mi E of Rolinda
Cause: Heavy Rain
Reported by: Storm Chaser
Coordinates: 36.720, -120.060

Strong thunderstorms caused streets to flood and be closed in the Kerman area.

Hail, Fresno

When: October 29, 4:44 PM PST to 4:45 PM PST
Where: Fresno County, 0.55 mi E of Kerman
Measured: 0.75 in hail
Reported by: Storm Chaser
Coordinates: 36.720, -120.060

A storm chaser reported penny sized hail.

Hail, Kings

When: October 29, 4:49 PM PST to 4:53 PM PST
Where: Kings County, 0.56 mi W of Cimarron
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 36.300, -119.790

Trained spotter reported penny sized hail at Grangeville Road and Highway 41.

Hail, Fresno

When: October 29, 4:55 PM PST to 4:59 PM PST
Where: Fresno County, 0.89 mi NW of Hammond
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 36.780, -119.790

Penny sized hail occurred on the west side of Fresno.

Thunderstorm Wind, Fresno

When: October 29, 4:55 PM PST to 4:59 PM PST
Where: Fresno County, 0.89 mi NW of Hammond
Measured: 50 kt (58 mph) estimated gust
Property damage: $25,000
Reported by: Trained Spotter
Coordinates: 36.780, -119.790

A trained spotter reported trees down on the west side of Fresno.

Hail, Fresno

When: October 29, 5:03 PM PST to 5:06 PM PST
Where: Fresno County, 0.55 mi E of Selma
Measured: 1 in hail
Reported by: NWS Employee
Coordinates: 36.570, -119.610

A NWS employee observed quarter sized hail at Mount Whitney and Peach Roads.

Hail, Fresno

When: October 29, 5:08 PM PST to 5:12 PM PST
Where: Fresno County, 0.89 mi NE of Figarden
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 36.830, -119.860

Quarter sized hail in the northwest sector of Fresno.

Flood, Fresno

When: October 29, 5:20 PM PST to 9:00 PM PST
Where: Fresno County, 0.89 mi NE of Figarden to 3.42 mi NW of Fig Garden
Cause: Heavy Rain
Property damage: $500,000
Reported by: Newspaper
Coordinates: 36.830, -119.860

Newspapers and broadcast meteorologists reported a number of roadways flooded in Northwest Fresno. Numerous vehicles were stranded and water rescues occurred. Heavy rain caused a roof to collapse at an industrial plant on the northwest side of the city. Damages were estimated at 250,000 to the roof structure alone.

Thunderstorm Wind, Fresno

When: October 29, 5:20 PM PST to 5:25 PM PST
Where: Fresno County, 0.89 mi NW of Hammond
Measured: 50 kt (58 mph) estimated gust
Property damage: $50,000
Reported by: Broadcast Media
Coordinates: 36.780, -119.790

Downed powerlines caused power outages to 16,000 customers, according to local Broadcast media in Fresno.

Thunderstorm Wind, Merced

When: October 29, 5:25 PM PST to 5:28 PM PST
Where: Merced County, Cregan
Measured: 55 kt (63 mph) estimated gust
Property damage: $60,000
Reported by: Newspaper
Coordinates: 37.300, -120.480

The local newspaper reported at least 8 downed trees, observed by Public Works Crews. Some powerlines were also downed.

Flash Flood, Madera

When: October 29, 5:32 PM PST to 7:30 PM PST
Where: Madera County, 5.7 mi ESE of Gregg to 3.64 mi S of Indian Spgs
Cause: Heavy Rain
Property damage: $25,000
Reported by: Law Enforcement
Coordinates: 36.860, -119.830

A vehicle was stuck in flash floodwaters at Freeway 99 and Shaw Avenue. There was also a tree downed in the slow lane.

Hail, Fresno

When: October 29, 5:32 PM PST to 5:35 PM PST
Where: Fresno County, 0.89 mi NW of Hammond
Measured: 0.88 in hail
Reported by: NWS Employee
Coordinates: 36.780, -119.790

A NWS employee observed nickel sized hail in Downtown Fresno at the intersection of Manning and Mendocino Roads.

Flash Flood, Kern

When: October 29, 6:00 PM PST to 9:00 PM PST
Where: Kern County, 1.49 mi SSW of Cable to 0.38 mi SSW of Tehachapi Mtn Vly Ap
Cause: Heavy Rain
Property damage: $10,000
Reported by: Trained Spotter
Coordinates: 35.130, -118.510

Debris was reported on the roadway causing the road to be closed.

Thunderstorm Wind, Fresno

When: October 29, 6:06 PM PST to 6:10 PM PST
Where: Fresno County, 0.89 mi NW of Hammond
Measured: 50 kt (58 mph) estimated gust
Property damage: $8,000
Reported by: Law Enforcement
Coordinates: 36.780, -119.790

Local police reported a tree down at Gettysburg Avenue and Van Ness Boulevard.

Thunderstorm Wind, Tulare

When: October 29, 6:06 PM PST to 6:12 PM PST
Where: Tulare County, 0.89 mi SW of Porterville
Measured: 50 kt (58 mph) estimated gust
Property damage: $30,000
Reported by: Law Enforcement
Coordinates: 36.060, -119.030

Local police in Tulare reported trees and powerlines downed.

Thunderstorm Wind, Tulare

When: October 29, 6:08 PM PST to 6:12 PM PST
Where: Tulare County, 0.56 mi E of Cinowths Corner to 1.87 mi W of Lemoncove
Measured: 62 kt (71 mph) estimated gust
Property damage: $110,000
Reported by: Law Enforcement
Coordinates: 36.330, -119.320

Powerlines and trees were downed on roadways. Boats were damaged at a Lake Kaweah boat dock. It was estimated that 200 boats were affected by severe thunderstorm wind gusts as the lake boat dock was cut loose.

Flood, Tulare

When: October 29, 6:15 PM PST to 10:00 PM PST
Where: Tulare County, 0.56 mi E of Cinowths Corner to 1.75 mi SE of Patterson Tract
Cause: Heavy Rain
Property damage: $20,000
Reported by: Newspaper
Coordinates: 36.330, -119.320

Newspaper reports several roadways flooded in the City of Visalia, mainly in the downtown and southside areas. The time was estimated using radar data and newspaper accounts.

Thunderstorm Wind, Tulare

When: October 29, 6:15 PM PST to 6:20 PM PST
Where: Tulare County, 0.56 mi E of Cinowths Corner
Measured: 55 kt (63 mph) estimated gust
Property damage: $150,000
Reported by: Newspaper
Coordinates: 36.330, -119.320

Newspaper accounts of trees downed on two houses causing property damages. One house had roof and structural damage.

Thunderstorm Wind, Tulare

When: October 29, 6:25 PM PST to 6:30 PM PST
Where: Tulare County, 1.49 mi SSE of Tulare
Measured: 50 kt (58 mph) estimated gust
Property damage: $60,000
Reported by: Newspaper
Coordinates: 36.200, -119.340

There were several reports of trees downed in the city of Tulare. There were also reports of trees and power lines downed in the town of Lindsay. A tree fell on a family's automobile between Visalia and Tulare.

Thunderstorm Wind, Mariposa

When: October 29, 6:45 PM PST to 6:48 PM PST
Where: Mariposa County, 3.01 mi SE of South Fork
Measured: 61 kt (70 mph) estimated gust
Reported by: Mesonet
Coordinates: 37.620, -119.840

A Mesonet station reported a wind gust of 61 knots in association with a severe thunderstorm near Yosemite National Park.

Thunderstorm Wind, Tulare

When: October 29, 6:49 PM PST to 6:54 PM PST
Where: Tulare County, Lemoncove
Measured: 50 kt (58 mph) estimated gust
Property damage: $22,000
Reported by: Trained Spotter
Coordinates: 36.380, -119.020

Trees and powerlines were downed causing power outages.

Thunderstorm Wind, Tulare

When: October 29, 7:00 PM PST to 7:08 PM PST
Where: Tulare County, Lodgepole
Measured: 50 kt (58 mph) estimated gust
Property damage: $12,000
Reported by: Park/Forest Service
Coordinates: 36.600, -118.730

The Park Service reported a few trees downed.

Flood, Mariposa

When: October 29, 7:30 PM PST to 9:30 PM PST
Where: Mariposa County, 1.29 mi WSW of Yosemite Vlg to 13.17 mi NE of Yosemite Natl Park
Cause: Heavy Rain
Reported by: Park/Forest Service
Coordinates: 37.740, -119.600

The Park Service reported minor flooding of road surfaces at low water crossings.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

Every storm in California in 2007 Every state in 2007 This day in weather history Warnings in California, October 2007

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: 64446, 64448, 64449, 64450, 64451, 64435, 64452, 64453, 64454, 64460, 64455, 64456, 64439, 64461, 64462, 64436, 64457, 64438, 64463, 64464, 64465, 64442, 64466, 64467, 64470, 64468, 64469, 64443.