An upper level low, combined with monsoonal moisture, produced several heavy thunderstorms, which resulted in several reports of heavy rainfall recorded in short period of time across portions of San Diego and San Bernardino counties.
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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 upper level low, combined with monsoonal moisture, produced several heavy thunderstorms, which resulted in several reports of heavy rainfall recorded in short period of time across portions of San Diego and San Bernardino counties.
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 Jul 18, 8:16 AM PST, 3 hours 4 minutes earlier.
Area Forecast Discussion National Weather Service San Diego CA 916 AM PDT Fri Jul 18 2025 .SYNOPSIS... Monsoonal moisture will continue to bring chances for showers and thunderstorms across the region through Saturday afternoon. The best chances for thunderstorms with periods of locally moderate to heavy rainfall will be this afternoon in the mountains and high deserts. Dry conditions return on Sunday and continue through the middle of next week. Daytime high temperatures are expected to remain near or a little below seasonal averages through the middle of next week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Morning Update... Mid level clouds continue to push in from the northwest. Some of these are associated with light showers from stronger thunderstorms earlier this morning. Some areas from San Clemente into parts of the eastern/southern Inland Empire received near one quarter of an inch of rainfall. Meanwhile, the marine layer is maintaining its grip across western San Diego County, shrouding the coastal slopes in fog with a "no sky July" morning across the San Diego metro area. These low clouds will shrink back to the coast later this morning. An area of low pressure will move northward today, helping to pull in more monsoonal moisture across the area. Chances for thunderstorms are in the forecast for mountainous regions and parts of the Coachella Valley and high desert. Hi-res models show convection forming after 12 noon as NBM chances for thunder are 25-40 percent. Anyone who sees these storms may also see small hail and gusty winds. The low will weaken and move northward by Saturday, keeping chances of storms limited to the Riverside/SBD Co mountain areas. .Previous Discussion... For this afternoon...chances for periods of locally heavy rainfall increase significantly for the mtns and high deserts as daytime heating becomes a factor, providing added forcing for deep convection. High temperatures today will continue to be near or a little below seasonal averages Chances for showers/tstms decrease tonight as the upper low moves north and we lose what little forcing there is. Moisture and instability persist into Saturday afternoon so that when daytime heating returns, showers/tstms can once again develop over the mtns and deserts. Less vertical mixing above the marine layer will allow for the return of more extensive low clouds with patchy fog tonight into Sat morning. By Sunday, we lose most of the monsoonal moisture as we begin to see drier southwest flow aloft which will essentially end the threat of showers/tstms as we return to a more stable atmosphere. For Monday through the middle of next week...a low/trough will dominate the pattern over the west coast, displacing the sub- tropical high eastward over the Gulf Coast states. This will bring us near-seasonal temperatures with a persistent marine layer for low clouds and fog in the coastal areas and valleys each night and morning. && .AVIATION... 181530Z....Coast/Valleys...ISO-SCT SHRA based at around 10000 feet through 18Z, generally confined to Orange and Riverside counties. Coastal low clouds in San Diego County based at 1500-1800 feet and tops to 2000 feet will gradually clear by 17Z. TSRA 20% chance in inland valleys near the mountains 19-01Z. Low clouds return to coastal areas mainly after 05Z, with bases around 1500 feet MSL. Scatter out Saturday by 17Z. Mountains/Deserts...SCT-BKN clouds 10000-15000 feet. ISO-SCT SHRA and TSRA over the mountains and high desert 18-02Z, with CU/CB bases 7000-9000 feet MSL, tops to 40000 feet. Erratic wind gusts, strong up/downdrafts, and VIS restrictions possible with any storm that develops. Mostly clear after 03Z. && .MARINE... No hazardous marine weather expected through Tuesday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && PUBLIC...APR AVIATION/MARINE...MM
The national radar mosaic for the moment the first event began.
2 heavy rain. Local standard time, as filed.
Trained spotter reported heavy rainfall of around a half of an inch an hour, and hail up to 0.25 inches in diameter mixed in, with ponding occurring in the backyard.
A mesonet 2 miles SW of Big Bear reported 1.43 inches of rainfall, which fell from a storm, in a short period of time.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2025Every state in 2025This day in weather historyWarnings in California, July 2025
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 2026-10-01. Each event’s entry at NCEI: 1288903, 1288905.