A second cold trough moved through Southern California May 19-22nd. Showers and thunderstorms occurred throughout much of the region, and snow was observed in the mountain areas.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The episode as NWS SGX wrote it up.
A second cold trough moved through Southern California May 19-22nd. Showers and thunderstorms occurred throughout much of the region, and snow was observed in the mountain areas. One to five inches of snow fell in the mountain areas, with the most snowfall in the San Bernardino Mountains. Heavy rain and flash flooding occurred in the Inland Empire. High wind also occurred with the passage of the cold troughs.
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 May 19, 1:19 PM PST, 1 hour 41 minutes earlier.
Area Forecast Discussion
National Weather Service San Diego CA
219 PM PDT Sun May 19 2019
.SYNOPSIS...
An unseasonably cold storm system will drop south across California
today, moving over SoCal early Monday morning with periods of
showers and possible thunderstorms. Wintery weather will revisit
the mountains as the snow level falls below 6000 feet, resulting
in accumulating snow for many resort areas north of San Diego
County. Winds will be strong and gusty over all of the mountains,
deserts, and coastal waters all the way through Tuesday. Continued
cool Monday, with showers ending in the morning. Some scattered
light showers are possible on Tuesday, otherwise it will be mostly
dry and cool ahead of the next round of showers and mountain snow
to arrive on Wednesday. A deep marine layer will remain in place
through the week due to a strong onshore flow pattern, with
daytime temperatures remaining well below normal.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE...SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...
At 1 PM, water vapor satellite showed an upper-level low centered
just north of San Francisco, with a trough moving south over Point
Conception and another trough just to our south over northern
Baja. The precipitation from the first trough has mostly ended,
however colder air behind and strong, moist, onshore flow is
starting to help develop isolated showers across the Coastal
Basin. No lightning has been observed yet over our area, but the
storms developing this afternoon could have a few strikes. The
greatest chance for lightning will be this evening and overnight
as the second, colder trough moves across the region. Showers
could be heavy at times, and help snow levels lower a bit more
compared to surrounding areas in the mountains. Although light
snow fell down to 6000 ft overnight, the snow level quickly rose
to 7000-7500 ft by late morning. As the second trough moves across
the region later, snow levels will crash down to 5500 ft with
accumulations possible above 6000 ft. The stronger showers tonight
could create heavy snow at times, especially above 7000 ft. The
Winter Weather Advisory remains in effect through early Monday
morning for total snow accumulations of 1 to 3 inches from 6000 to
7000 ft, 3 to 6 inches above 7000 ft, and localized amounts up to
8 inches above 8000 ft. The coastal mountain slopes could see an
additional inch to inch and a half of precipitation by Monday
morning, with lesser amounts of a tenth or two as you head to the
coast.
Winds have also picked up today with strengthening pressure
gradients. the latest highest wind gust summary is on our webpage,
and includes a gust to 56 mph at Whitewater and 70 mph in Burns
Canyon. The Wind Advisory remains in effect for the desert
mountain slopes and adjacent desert areas through late Tuesday.
Westerly winds are looking even stronger late Tuesday as another
system takes aim at California. More precipitation and lower snow
levels return, with only a brief break in the precipitation and
strong winds late Monday. Multiple waves moving around the low
could create periods of precipitation Tuesday through Thursday.
Friday looks dry at this time, then wet weather could return again
for the weekend with another system moving across the region. This
pattern will keep high temperatures well below seasonal normals
for inland areas this time of year, with some areas staying 15 to
25 degrees below normal. Several areas could break their lowest
high temperature records over the past few days. Coastal
locations will only be a few degrees below normal since they are
usually cloudy and cool this time of year anyway.
&&
.AVIATION...
192100Z...Coast/Valleys...BKN-OVC low clouds with VRB bases 2000-
6000 FT MSL should briefly clear from terminals 19/22Z-20/03Z. MOD
confidence in SHRA returning to TAF sites late evening after 04Z
with similar cigs. Confidence is lower in KSNA seeing SHRA. Coverage
will then decrease from NW to SE...Orange County/Inland Empire
clearing around 20/14Z, with KSAN/KCRQ likely clearing 3 to 5 hrs
later. MOD confidence in period of stronger W SFC winds gusting 20-
25 kts through 20/03Z at coastal/valley TAFs.
Mountains/Deserts...OVC skies with scattered SHRA will persist over
the mtns into tomorrow morning. W winds will continue to strengthen
this afternoon, with MOD-STG UDDFTS and LLWS likely over and east of
the mtns where SFC winds are expected to range between 25-35 kts,
with gusts 40-55 kts. Clouds will obscure terrain along the coastal
slopes at times, reducing vis to 2-4 SM in BR. Strong NW winds late
afternoon and evening at KPSP/KTRM, with gusts to 30 to 35 kts. AWW
in effect 19/20Z-20/09Z for KPSP for possible gusts 35-40 kts.
&&
.MARINE...
WNW winds will increase in strength late tonight with gusts to 25
kts over the Outer Waters early Mon. Winds will weaken slightly Mon
evening into Tue morning, but could remain above Small Craft
Advisory thresholds over the Outer Waters, before quickly increasing
late Tue into Wed. Gusts of 30-35 kts look possible over the Outer
Waters late Tue. Winds will be accompanied by combined seas of 10-14
ft and rough conditions. A Small Craft Advisory remains in effect
through 3 PM Wednesday.
Showers along with a slight chance of thunderstorms and an isolated
waterspout will be possible late this afternoon and evening over the
coastal waters.
&&
.BEACHES...
A slight chance of thunderstorms late afternoon and evening with an
associated risk of lightning at the beaches. Confidence is low-
moderate.
Building medium-period WNW swell will generate locally elevated surf
conditions Monday into early Tuesday, with surf up to 7 FT,
especially in southern San Diego County. A Beach Hazards Statement
is in effect between 3 AM Monday and 9 AM Tuesday.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Winter Weather Advisory until 5 AM PDT Monday for Riverside
County Mountains-San Bernardino County Mountains.
Wind Advisory until 11 PM PDT Tuesday for Apple and Lucerne
Valleys-Coachella Valley-Riverside County Mountains-San
Bernardino County Mountains-San Diego County Deserts-San
Diego County Mountains-San Gorgonio Pass Near Banning.
Beach Hazards Statement from late tonight through Tuesday
morning for Orange County Coastal Areas-San Diego County
Coastal Areas.
PZ...Small Craft Advisory until 3 PM PDT Wednesday 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...JJT
AVIATION/MARINE/BEACHES...RodriguezThe Edwards AFB radar (KEYX), 129 km away, was scanning. The volume nearest the first event began at 21:01 UTC.
3 flash flood, 2 high wind, 2 heavy snow, 1 strong wind, 1 flood. Local standard time, as filed.
Mesonet Burns Canyon reported a peak wind gust of 68 knots between 1500 and 1600 PST on May 19th.
Snow fell in the San Bernardino Mountains early in the morning on May 20th, dropping 1-5 inches. Chain controls were in effect for the morning hours of May 20th.
Mesonet Harrison Park reported a peak wind gust of 68 knots between 2200 and 2300 PST on May 20th.
Trained spotter reported power lines down in Lucerne Valley due to strong winds. Power was out for approximately 4-5 hours.
Snow fell in the Riverside County Mountains on May 22nd, dropping 1-4 inches of snow.
CalTrans reported a car stuck on Monte Vista Ave and Phillips Ave north of Chino. Water got inside of the vehicle.
CalTrans reported numerous areas of highway 60 near Chino flooded out due to heavy rain.
Spotter reported flash flooding and a swift water rescue just north of Upland. It was reported that the vehicle lost control, flipped over and was taking on water.
Spotter reported urban flooding and water going over curbs at the intersection of La Palma and Brookhurst in Anaheim on May 22nd.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2019Every state in 2019This day in weather historyWarnings in California, May 2019
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: 830698, 830697, 830700, 830701, 831065, 830711, 830709, 830712, 830715.