California, 2019Flash Flooding and Flooding in California, December 4, 2019
December 4, 2019 · NWS SGX · 8 events in 4 counties and zones
A low pressure system moved over Southern California, bringing rain and high level mountain snow. 50 inch and 1 inch, with locally higher amounts up to 2 inches in the valleys.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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
- Deaths
- 2
- Injuries
- 0
- Property damage
- $809,000
- 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.
A low pressure system moved over Southern California, bringing rain and high level mountain snow. Coast and valley areas received between 0.50 inch and 1 inch, with locally higher amounts up to 2 inches in the valleys. Mountain areas received 2 to 3 inches, with locally higher amounts in the San Bernardino Mountains. Desert areas received 0.25 to 0.50 inch. Heavy rain resulted in river flooding along the San Diego River, where water levels at Fashion Valley topped out at 9 feet (action stage). Many roads around Fashion Valley Mall were closed due to flooding. The Tijuana River also flooded the Tijuana River Valley, closing roads and trapping cars in flood waters. A hiker went missing on Mount Baldy on December 8th, and a search and rescue worker died on December 14th during a search for the missing hiker.
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 San Diego, CA wrote its last area forecast discussion before the first event at Dec 4, 3:30 AM PST, 1 hour 30 minutes earlier.
Area forecast discussion, Dec 4, 3:30 AM PST, 1 hour 30 minutes before
Area Forecast Discussion
National Weather Service San Diego CA
330 AM PST Wed Dec 4 2019
.SYNOPSIS...
A low pressure system will move eastward across central and
southern California today bringing periods of moderate to heavy
rainfall from around day break into the afternoon. Decreasing
showers will end early Thursday, then drier and a little warmer
through Friday. A low pressure system off the West Coast could
bring some occasional periods of light rainfall for the weekend.
Drier with a warming trend early next week.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
.SHORT TERM (Today through Friday)...
The center of a closed low pressure system is west of Point
Conception early this morning. It will move to near the coast
during the late morning and into central California this
afternoon. It is directing a flow of moisture from the south into
southern California.
Lighter rainfall is expected to begin intensifying around
daybreak with periods of moderate to heavy rainfall continuing
into the afternoon. There is also a slight chance of thunderstorms
during the late morning and early afternoon. Showers will
decrease from the west during the mid to late afternoon. Showers
are expected to end late tonight or early Thursday.
Rainfall will range from 0.75 to 1.25 inch near the coast to 1.5
to 2.5 inches in the mountains with local amounts exceeding 3
inches. In the high desert, rainfall of around one half inch is
expected with one quarter to locally one half inch in the lower
deserts.
That low pressure system will move into Utah by early Thursday
morning with high pressure moving into California. Any lingering
showers should end by early Thursday. It will then be drier and
a little warming trough Friday.
&&
.LONG TERM (Saturday through Monday)...
The center of a low pressure system off the West Coast will move
to near the Oregon coast by late Saturday with west to southwest
flow aloft across southern California. Some occasional mostly
light precipitation is possible over the weekend, but with low
confidence in the timing and locations. By early next week, high
pressure will develop near the West Coast with drying and some
warming for southwest California.
&&
.AVIATION...
041100Z...RA and lowest clouds/vis expected through 20Z moving
west to east across the region. During this time cigs will be
1000-2000 feet MSL with vis 2-5SM in RA with much of the mountains
obscured in RA/FG. There is also a small chance of TSRA between
17-23Z. Rapidly improving after 20Z from west to east with P6SM
and BKN025 in decreasing -SHRA through about 01Z. Strong westerly
winds 20-30 kts with gusts to 40 kts after 17Z over portions of
mountains and deserts. Isolated -SHRA mainly against mountains
into tonight. Coast and deserts intermittently scatter out after
23Z.
&&
.MARINE...
Southerly winds with gusts 20-25 kts are expected this morning
resulting in hazardous boating conditions. Slight chance of a
thunderstorm late morning and early afternoon. Winds will switch to
the west and decrease this afternoon. A Small Craft Advisory is in
effect through 2 PM. No additional marine weather hazards are
expected tonight through Sunday.
&&
.BEACHES...
Slight chance of thunderstorms late morning through early afternoon
mainly in Orange County, making lightning strikes remotely possible.
&&
.SKYWARN...
Skywarn activation is requested beginning at 6 AM and continuing
into the afternoon.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Flash Flood Watch from 6 AM PST this morning through this
afternoon for Orange County Coastal Areas-Orange County
Inland Areas-Riverside County Mountains-San Bernardino
County Mountains-San Bernardino and Riverside County
Valleys-The Inland Empire-San Diego County Coastal Areas-
San Diego County Mountains-San Diego County Valleys-Santa
Ana Mountains and Foothills.
PZ...Small Craft Advisory until 2 PM PST this afternoon for Coastal
Waters from San Mateo Point to the Mexican Border and out
to 30 nm-Waters from San Mateo point to the Mexican Border
Extending 30 to 60 nm out including San Clemente Island.
&&
PUBLIC...17
AVIATION/MARINE/BEACHES...MMEvent by event
4 flood, 3 flash flood, 1 winter weather. Local standard time, as filed.
Winter Weather, San Bernardino County Mountains
- When
- December 4, 5:00 AM PST to 5:00 PM PST
- Where
- San Bernardino County Mountains forecast zone
- Deaths
- 0 direct, 2 indirect
- Reported by
- Broadcast Media
- Coordinates
- 34.841, -116.178 (the zone’s center; the record gives no point)
Broadcast media reported a missing hiker on Mount Baldy on December 8th, with treacherous winter weather conditions on the mountain. A search and rescue worker died on December 14th after falling down an icy ravine while searching for the hiker. All search and rescue operations were halted after the worker death. The missing hiker was never found.
Flood, San Diego
- When
- December 4, 9:00 AM PST to 12:00 PM PST
- Where
- San Diego County, 0.13 mi ESE of Crest
- Cause
- Heavy Rain
- Reported by
- County Official
- Coordinates
- 32.779, -116.868
Dehesa Road, just east of El Cajon, had debris across the road approximately 3-4 feet wide.
Flash Flood, Riverside
- When
- December 4, 9:30 AM PST to 12:30 PM PST
- Where
- Riverside County, 6.58 mi WNW of Bly
- Cause
- Heavy Rain
- Reported by
- Department of Highways
- Coordinates
- 34.031, -117.629
Highway 60 at Grove Ave was flooded due to heavy rain.
Flash Flood, Riverside
- When
- December 4, 10:00 AM PST to 3:00 PM PST
- Where
- Riverside County, 1.28 mi E of Craf to 1.22 mi E of Craf
- Cause
- Heavy Rain
- Property damage
- $759,000
- Reported by
- Department of Highways
- Coordinates
- 34.048, -117.158
Interstate 10 in Redlands had a large sinkhole on the shoulder of the interstate due to flooding. Total cost to repair the damage was $759,000.
Flood, San Diego
- When
- December 4, 10:00 AM PST to 3:00 PM PST
- Where
- San Diego County, 2.1 mi NNW of Del Dios to 2.07 mi NNW of Del Dios
- Cause
- Heavy Rain
- Property damage
- $10,000
- Reported by
- Department of Highways
- Coordinates
- 33.099, -117.131
Harmony Grove flooding over low lying water crossing from Escondido Creek. This is a flood prone area that has flood gates and cameras.
Flash Flood, San Bernardino
- When
- December 4, 11:00 AM PST to 2:00 PM PST
- Where
- San Bernardino County, 1.1 mi SW of Phelan to 1.08 mi SW of Phelan
- Cause
- Heavy Rain
- Reported by
- Department of Highways
- Coordinates
- 34.408, -117.582
Highway 138 eastbound near Phelan flooded and was closed down. Tractor trailers were stalled out in the flood waters.
Flood, San Diego
- When
- December 4, 12:00 PM PST to 4:00 PM PST
- Where
- San Diego County, 0.98 mi ENE of (Nrs)naf Imperial Be to 1.01 mi ENE of (Nrs)naf Imperial Be
- Cause
- Heavy Rain
- Property damage
- $40,000
- Reported by
- Department of Highways
- Coordinates
- 32.555, -117.084
Hollister Street flooded in the Tijuana River Valley. Cars were stalled in 2 feet of water, some requiring water rescues.
Flood, San Diego
- When
- December 4, 3:00 PM PST to 6:00 PM PST
- Where
- San Diego County, 1.41 mi NW of Hillcrest to 1.4 mi NW of Hillcrest
- Cause
- Heavy Rain
- Reported by
- Department of Highways
- Coordinates
- 32.766, -117.164
Avenida del Rio flooded at Fashion Valley Mall due to the San Diego River reaching 9 feet. Water was approximately 12 to 18 inches deep.
- Winter Weather
- Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.
- Flood
- Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
- 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.
- Flash Flood and Flood in Arizona, December 4 to 10, 20191 death · 2 events
- Winter Weather in Pennsylvania, December 4 to 5, 20196 events
- Dense Fog in Nevada, December 4 to 6, 20196 events
- Dense Fog in California, December 4 to 6, 20194 events
- Flooding in California, December 4, 20193 events
- Winter Weather in West Virginia, December 4 to 5, 20193 events
- High Wind in North Carolina, December 4 to 5, 2019$9,000 · 58 kt wind · 3 events
- Flash Flooding in Arizona, December 4, 2019$2,000 · 2 events
- Winter Weather in West Virginia, December 4 to 5, 20192 events
- Winter Weather in Maryland, December 4 to 5, 20191 event
- Lake-Effect Snow in Pennsylvania, December 4 to 5, 20191 event
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 2026-09-24. Each event’s entry at NCEI: 870577, 869745, 869740, 869742, 870507, 869743, 869741, 869744.