Heavy rain fell yet again on August 16th, causing flooding and debris flows on Highway 38 in San Bernardino County. This particular highway was already susceptible to flooding and debris flows due to its proximity to the El Dorado burn scar, and had already experienced several debris flows from late July through mid-August.
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.
Heavy rain fell yet again on August 16th, causing flooding and debris flows on Highway 38 in San Bernardino County. This particular highway was already susceptible to flooding and debris flows due to its proximity to the El Dorado burn scar, and had already experienced several debris flows from late July through mid-August.
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 Aug 16, 8:41 AM PST, 2 hours 49 minutes earlier.
Area Forecast Discussion
National Weather Service San Diego CA
941 AM PDT Tue Aug 16 2022
.SYNOPSIS...
There will be fluctuations during the next week in monsoonal
moisture and chances for afternoon and early evening thunderstorms
in the mountains and deserts. Today is expected to be similar to
Monday, then a little drier with fewer thunderstorms for Wednesday
and Thursday. Then increasing moisture for Friday and Saturday
with greater chances for thunderstorms and inland high
temperatures not as hot. Then a drying trend for Sunday and Monday
with warmer high temperatures for inland areas early next week as
the drying occurs.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
.Morning Update...
Low clouds near the coast are slowly retreating at this hour via
latest GOES imagery. Also at this hour...soup! Low level wind
flow from the southeast is bringing very humid conditions to
portions of the southern Coachella Valley into Imperial County,
where we are seeing dew points into the mid 70s! We will see
another warm and humid day across Southern California today with
highs at or above 100 degrees across portions of the deserts and
Inland Empire. The forecast continues to call for a subtle cooling
trend as we head into the end of the week, though the humidity
will remain for all.
In terms of thunderstorms, the typical areas around the mountains
have the best chance for storm development today. A slight drying
trend over the next couple of days will make for only isolated
storm chances through Thursday. The forecast continues to call for
a larger influx of moisture by Friday and Saturday, which will
generate more scattered shower and storm activity across the
region. Areas west of the mountains will even have a chance to
see an isolated thunderstorm or two, especially on Saturday.
.Previous Forecast (252 AM Today)...
.SHORT TERM (Today through Thursday)...
Not much change from Monday with isolated to scattered
thunderstorms developing in the mountains during the afternoon and
moving toward the deserts as the sea breeze moves inland. Then a
little drier for Wednesday and Thursday with afternoon showers
and thunderstorms, mainly over the mountains, more isolated.
The Heat Advisory continues for the Inland Empire through
Wednesday. Today will probably be the hottest day with Wednesday a
degree or so cooler, then a few degrees cooler for Thursday.
Areas of night and morning coastal low clouds and fog will extend
locally inland into the far western valleys in San Diego County at
times and across portions of the Orange County coastal plain.
&&
.LONG TERM (Friday through Monday)...
An influx of moisture is expected for Friday and Saturday with
more clouds and high temperatures for inland areas not quite as
hot. There will be increasing chances for mainly afternoon and
early evening showers and thunderstorms, mainly in the mountains
and deserts. NBM chances for measurable rainfall are a few percent
less than for forecasts from 24 hours ago.
This will be followed by a drying trend for Sunday and Monday as
high pressure over the eastern Pacific expands across southern
California with warmer high temperatures for inland areas as the
drying occurs.
&&
.AVIATION...
161630Z...Coast/Valleys...FEW low clouds at the beaches through this
afternoon but no CIG/VIS impacts at coastal TAF sites through 03Z
Wed. Chances for SCT-BKN low clouds at coastal TAF sites return
after 06Z Wed with bases 700-900 ft MSL. Otherwise, SCT100 with
unrestricted vis through tonight.
Mountains/Deserts...ISOLD-SCT SHRA/TSRA developing over the
mountains and high deserts after 19Z today with CB bases 10,000 feet
MSL and tops 35,000 feet. Gusty and erratic winds and brief heavy
rain vcnty TSRA. SHRA/TSRA dissipating by 17/03Z.
&&
.MARINE...
No hazardous marine weather through Friday.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory until 8 PM PDT Wednesday for San Bernardino and
Riverside County Valleys-The Inland Empire.
PZ...None.
&&
UPDATE/PUBLIC...APR/17
AVIATION/MARINE...PGThe national radar mosaic for the moment the first event began.
2 strong wind, 1 flood. Local standard time, as filed.
Mud and water crossing Highway 38. Highway remained closed for emergency repairs and drainage debris removal. Enhanced debris flow and runoff from the El Dorado Burn Scar. Video shared via CalTrans 8.
Mesonet station BVDSD Boulevard West (SDGE) reported a peak wind gust of 47 mph as a thunderstorm moved across the US/Mexico border along I-8. Temperature dropped from 94 degrees to 75 degrees.
A thunderstorm near Morongo and Cabazon produced wind gusts of 45-55 mph near San Gorgonio Pass, including at the following Mesonet sites:
SoCal Edison site Lion Canyon (445SE): 53 mph.|SoCal Edison site East Canyon (SCE365): 48 mph.|SoCal Edison site Stubble Canyon (161SCE): 47 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2022Every state in 2022This day in weather historyWarnings in California, August 2022
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: 1045795, 1047250, 1047249.