Strong surface high pressure over the Great Basin brought intense east to northeast winds to Southern California on February 25th and 26th. The strongest winds were observed in the wind-prone passes and canyons, especially in San Diego County.
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.
Strong surface high pressure over the Great Basin brought intense east to northeast winds to Southern California on February 25th and 26th. The strongest winds were observed in the wind-prone passes and canyons, especially in San Diego County. A peak wind gust of 106 mph from a mountain wave was recorded at Sill Hill in the San Diego County mountains. Many mountain locations reported wind gusts of 65-75 mph. Two tractor trailers were overturned on I-8 in San Diego County, and many trees fell due to high wind.
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 Feb 24, 8:53 PM PST, 3 hours 7 minutes earlier.
Area Forecast Discussion
National Weather Service San Diego CA
853 PM PST Mon Feb 24 2020
.SYNOPSIS...
Fair and warmer weather is expected this week under building high
pressure and offshore flow. Gusty east to northeast winds are
expected through passes and along coastal foothill areas Tuesday
through Thursday. Our next chance for showers comes late Sunday into
Monday as a cold storm system drops down the Coast.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
...Update...
It was warmer today than the chilly weather we saw this past
weekend. The warmest readings were in the Coachella Valley with
Palm Springs soaring to 89 degrees. Offshore winds will be taking
over and downslope warming will occur west of the mountains, so
this will really warm up the coast and valleys, while slight
cooling occurs over the deserts as slightly cooler air moves in
from the east. Then on Thursday-Friday, the deserts warm back up
as a ridge builds in overhead, with warmth continuing west of the
mountains. Thursday and Friday will likely be the warmest days of
the week before an upper level trough begins to move in from the
north. Cooling will occur over the weekend, especially on Sunday,
when showers could make a return. Gusty offshore winds will blow
below passes and canyons peaking tomorrow and Wednesday morning.
...Previous Discussion (Issued at 100 PM PST Mon Feb 24 2020)...
Skies were clear across the forecast area early this afternoon.
Surface pressure gradients were trending offshore and a wind shift
from the north with gusts over 25 MPH was noted at some sites over
northern portions of the forecast area.
A strong sfc high will build south over the Rockies/Great Basin
tonight through Wednesday. The increasing pressure gradient and cold
air surge will result in Santa Ana conditions over SoCal Tuesday
through Thursday with low RH and gusty winds in the usual wind-
prone areas. A Wind Advisory has been posted over most of the mts
and into some valley areas as well. Some wind gusts to 50 MPH are
expected, but a few hot spots in the wind-prone areas could easily
top that. Much of the coast will be spared the wind, but will feel
the heat as temperatures rise to 8-15F above average. The nights
should still be quite cool where winds drop off, but temps will
remain elevated in windy areas.
The warm conditions will persist into Friday, even as high clouds
thicken ahead of a weak subtropical system. Of more concern will be
a cold trough digging south along the Coast this coming weekend.
The various global models have been consistent digging this system
and the associated ensembles have been mostly wet over SoCal as
well, so POPS have been increased a bit. There is still a lot of
time and model runs to confirm, and this type of system is
inherently tricky to forecast. If it develops to full potential, we
could get some significant precipitation late in the weekend or
early next week.
&&
.AVIATION...
250420Z...Unrestricted vis and mostly clear skies through Tuesday.
Northeast winds up to 20 kt with gusts up to 40 kt are expected over
the mountains, through passes, and locally into the foothills
starting around 12Z Tue. Locally stronger winds are possible through
canyons and passes. Moderate to strong up/downdrafts and wind shear
near the mountains can be expected. Winds are expected to weaken
slightly overnight Tue before picking up again Wed morning.
&&
.MARINE...
No hazardous marine weather is expected through Thursday.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from 10 AM Tuesday to noon PST Thursday for San
Diego County Mountains-San Diego County Valleys.
Wind Advisory from 4 AM Tuesday to noon PST Thursday for
Riverside County Mountains-San Bernardino County Mountains-
San Bernardino and Riverside County Valleys-The Inland
Empire-San Gorgonio Pass Near Banning-Santa Ana Mountains
and Foothills.
PZ...NONE.
&&
PUBLIC...Gregoria (Update)/10 (Prev Discussion)
AVIATION/MARINE...COThe national radar mosaic for the moment the first event began.
4 high wind, 1 strong wind. Local standard time, as filed.
Buckman Springs reported a peak wind gust of 63 knots between 0000 and 0100 PST on February 25th.
Caltrans and Highway Patrol reported semi on side at 1200 PST and partially down an embankment. Additional semis on side between 0400 and 0600 PST blocking lanes on I-8. Widespread wind gusts 50 to 70 mph on I-8 to Highway 79.
Sill Hill reported a peak wind gust of 92 knots between 0000 and 0100 PST on February 26th.
A 75 year old pine tree fell on house and garage in Encinitas. The tree took out power pole. No injuries were reported. Mesonet site in Solana Beach recorded 34 knots and 36 knots at Elfin Forest. 39 knots in San Dieguito.
Highland Springs reported a peak wind gust of 61 knots between 0700 and 0800 PST on February 26th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, February 2020
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: 879100, 879101, 879104, 879105, 879106.