An early season monsoon weather pattern led to areas of lightning and wind, as well as some small wildfires.
Every event with a place to put it; 2 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.
An early season monsoon weather pattern led to areas of lightning and wind, as well as some small wildfires.
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 Jun 19, 2:41 AM PST, 4 hours 19 minutes earlier.
Area Forecast Discussion
National Weather Service San Diego CA
341 AM PDT Sat Jun 19 2021
.SYNOPSIS...
The marine layer and onshore flow will maintain comfortable Summer
weather along the coast and in the far western valleys, with
night and morning low clouds and patchy fog, while hot weather
prevails farther inland through Monday. A weak upper-level
disturbance will continue higher clouds and even a chance for an
isolated thunderstorm or two over mainly far northern portions of
the forecast area today. After Monday, the strong ridge over the
Southwest will weaken slightly and shift south as low pressure
approaches the West Coast. This will bring stronger onshore flow
and spread cooling slowly inland next week.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
-Highlights-
* Very high heat risk continues over the deserts today
* Coast and western valleys remain modified by the marine layer
The upper ridge remains in control over the Desert Southwest. This
will continue to lead to very hot conditions across the deserts,
but the good news is that cooling will finally begin to occur
Sunday and through the middle part of next week. This will happen
as an upper trough develops and moves towards California from the
Pacific. This feature will move inland across NorCal by the
middle part of next week, resulting in stronger onshore wind flow
early/mid week, gradual cooling area wide, and a deeper marine
layer. Lack of moisture precludes any rain chances.
Very high heat risk will continue across the desert regions today,
but this risk will gradually lessen early next week as the ridge
strength eases.
West winds will pick up and will blow a bit stronger through and
below the mountain passes (desert sides) early-mid week with peak
gusts to about 40 mph.
Ensembles show no huge outliers and depict a gradual building
ridge over the western U.S. next weekend. This would lead to
conditions becoming hotter again inland, but likely not as intense
as this current heat wave. The most anomalous heights look to be
positioned over the Pacific Northwest.
&&
.AVIATION...
191035Z...Coasts/Valleys...Low clouds will continue to cover parts
of the coast and western valleys through the early morning hours.
Moderate confidence in bases staying within the 700-1000 ft MSL
range, though locally lower bases are possible near 400 ft MSL after
12Z. Vis restricted 1-3 sm near areas of higher terrain. Clearing
will occur near 15-17Z inland and coastal areas 17-19Z, though areas
along the coast and up to 3 mi inland may remain BKN-OVC through
much of the afternoon including KSAN/KRQ. Stratus will begin to move
back inland after 01Z this evening with similar lower bases.
Mountains/Deserts...FEW-SCT clouds at/above 10,000 ft MSL and
unrestricted vis through Saturday evening. A few Cu with bases near
15,000 ft MSL may develop over the mountain crests after 18Z,
dissipating by sunset. West winds with sfc gusts 25-35 kt developing
along the desert mountain slopes into the deserts and through the
passes Saturday afternoon and evening, where KPSP will see gusty
northwest winds at times.
&&
.MARINE...
Breezy northwest winds will occur each afternoon and evening near 20
knots starting on Monday in the outer waters. Otherwise, no
hazardous marine weather is expected through Thursday.
&&
.FIRE WEATHER...
Extreme heat, low RH of 10-15%, and locally gusty westerly winds
will maintain elevated fire weather conditions well inland through
Monday. West winds of 25-35 mph with peak gusts of 35-45 mph will
occur late each day through and below the San Gorgonio Pass, and on
some of the desert slopes of the mountains.
High mixing heights in the mountains and deserts will increase the
potential for plume-driven fire growth each day as well.
Cooling and slightly higher humidity will work inland after Monday.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning until 9 PM PDT this evening for Riverside
County Mountains-San Bernardino County Mountains-San
Bernardino and Riverside County Valleys-The Inland Empire-
San Diego County Valleys-San Gorgonio Pass Near Banning.
Excessive Heat Warning until 9 PM PDT Sunday for Apple and
Lucerne Valleys-Coachella Valley-San Diego County Deserts-
San Diego County Mountains.
PZ...NONE.
&&
PUBLIC...Gregoria
AVIATION/MARINE...APRThe San Diego radar (KNKX), 28 km away, was scanning. The volume nearest the first event began at 22:59 UTC.
2 wildfire, 1 lightning. Local standard time, as filed.
The Overland fire burned 515 acres with temperatures over 110 degrees. This fire occurred near Canebrake Canyon Road and Great Southern Overland Stage Route, east of Mount Laguna. No structures damaged.
Emergency manager relayed a report of a tree struck by lightning in Cathedral City as reported by KESQ media. Radar detected rain cells and lightning was also detected in the Coachella Valley. The Cathedral City fire department received reports at the 36000 block of Bankside Drive. The palm tree was immediately next to at least 2 home residences.
The Mesa fire started southwest of Pala near Highway 76 and burned 350 acres. Brief evacuation warnings were issued on the 23rd, and Highway 76 temporary closed. No reports of damaged structures.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2021Every state in 2021This day in weather historyWarnings in California, June 2021
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: 967133, 966956, 967114.