Considerable moisture from Hurricane Dolores to the south, along with monsoon moisture from the southeast resulted in widespread showers and thunderstorms over most of the HSA for the 17th-19th. 71 inches at Lindbergh Field on the 18th (July 18 single-day and July monthly total).
Every event with a place to put it; 1 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.
Considerable moisture from Hurricane Dolores to the south, along with monsoon moisture from the southeast resulted in widespread showers and thunderstorms over most of the HSA for the 17th-19th. Rainfall ranged from one-half of an inch up to around 4 inches, including a record 1.71 inches at Lindbergh Field on the 18th (July 18 single-day and July monthly total). The San Diego River at Fashion Valley had 2 crests above monitor stage, 7.7 feet on the 18th and 8.8 feet on the 19th. The heavy rain resulted in a debris flow in the burn scar of Silverado Canyon, as well as flash flooding in Moreno Valley, Perris, and La Mesa on the 19th and a wet microburst in Tierrasanta on the 18th. The rain also caused the first Los Angeles Angels baseball game rain-out since 1995, and a rare 2-hour rain delay at the San Diego Padres baseball game. Over 2000 lightning strikes reported on July 18, some starting small brush fires. Microburst wind damage occurred in Tierrasanta, along with additional damage from a haboob in the Anza Borrego SP and wind damage from a thunderstorm in Palm Desert.
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 17, 12:27 PM PST, 3 hours 18 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
127 PM PDT FRI JUL 17 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING ALOFT WILL BRING SLIGHT WARMING TODAY WITH
MOSTLY SUNNY SKIES. TROPICAL MOISTURE FROM TROPICAL CYCLONE DOLORES
WILL BRING CLOUDS...WARM AND MUGGY CONDITIONS...AND ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS THIS WEEKEND. SOME REMNANT
MOISTURE WILL BRING THE CHANCE FOR AFTERNOON AND EARLY EVENING
THUNDERSTORMS AND SHOWERS FOR THE MOUNTAINS AND DESERTS MONDAY.
GRADUALLY DRIER FOR TUESDAY THROUGH FRIDAY OF NEXT WEEK ALONG WITH A
RETURN OF THE NIGHT AND MORNING COASTAL AND WESTERN VALLEY LOW
CLOUDS AND PATCHY FOG.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
MARINE LAYER STRATUS WAS A BIT SHALLOWER THIS MORNING...AS EARLIER
VISIBLE SATELLITE SHOWED LOW CLOUDS COVERING THE COAST AND WESTERN
VALLEYS...BUT NOT QUITE INTO THE INLAND EMPIRE. THE 12Z MIRAMAR
SOUNDING SHOWED AN 8 DEG C INVERSION AT AROUND 2300 FEET MSL...WITH
SOUTHWEST FLOW ALOFT. STRATUS HAS CLEARED OUT NICELY ACCORDING TO
THE LATEST VISIBLE IMAGES. WITH A RIDGE BUILDING IN
ALOFT...TEMPERATURES CURRENTLY ARE A 3-7 DEGREES HIGHER THAN AT THIS
TIME YESTERDAY.
DOLORES IS NOW A TROPICAL STORM AND LOCATED 420 MILES WEST OF CABO
SAN LUCAS AS IT CONTINUES TO MOVE TO THE WEST-NORTHWEST. AS THE
RIDGE TO THE EAST CONTINUES TO EXPAND WESTWARD INTO SOUTHERN
CALIFORNIA AND BAJA...IT WILL STEER DOLORES TO MORE OF A NORTHWEST
MOVEMENT THROUGH THIS WEEKEND...EVENTUALLY REACHING A POINT 200-300
MILES WEST OF NORTHERN BAJA BY LATE SUNDAY NIGHT AS IT BECOMES A
REMNANT LOW OR TROPICAL DEPRESSION. INCREASING MOISTURE...SOME FROM
DOLORES AND SOME FROM NORTHWEST MEXICO...WILL ADVECT INTO THE REGION
STARTING TONIGHT AND CONTINUING THROUGH SUNDAY...RESULTING IN
PLENTIFUL CLOUDS...INCREASINGLY HUMID AND MUGGY CONDITIONS...AND
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS FROM THE COASTAL
WATERS TO THE DESERTS. GFS...NAM AND WRF SHOW PRECIPITABLE WATER
INCREASING TO 1.7-1.9 INCHES BY LATE SATURDAY AFTERNOON...AND
CONTINUING NEAR THOSE VALUES THROUGH SUNDAY. STARTING TONIGHT AND
CONTINUING THROUGH SUNDAY...THE BUFKIT FORECAST SOUNDINGS FROM THE
NAM AND GFS SHOW ELEVATED CAPE...WHICH INDICATES THAT THERE IS
ELEVATED INSTABILITY AND THE POTENTIAL FOR THUNDERSTORMS.
THERE WILL BE SMALL INCREASES IN MOISTURE THIS AFTERNOON UNDER
SOUTHWEST FLOW ALOFT...RESULTING IN SOME CUMULUS OVER THE MOUNTAINS
AND HIGH DESERTS. THE 19Z HRRR SHOWS SOME CONVECTION SPARKING OFF
THIS AFTERNOON OVER IMPERIAL COUNTY...WITH POSSIBLY SOME SPILLING
INTO OUR LOWER DESERTS...BUT CONFIDENCE IS LOW...ESPECIALLY WITH HOW
POOR THE 19Z HRRR INITIALIZED. MOISTURE CONTINUES TO INCREASE LATE
TONIGHT INTO SATURDAY MORNING...BUT NOT QUITE AS MUCH AS FOR THAT
TIME-PERIOD AS MODELS HAVE SHOWN PREVIOUSLY. NONE OF THE HIGH-RES
MODELS SHOW MUCH OF ANY ACCUMULATIONS DURING THAT TIME.
THUS...SHOWER/THUNDERSTORM CHANCES FOR OVERNIGHT TONIGHT ARE NOT
GREAT...BUT WILL KEEP IT IN THE FORECAST FOR NOW. IT MAY START OUT
AS MOSTLY VIRGA OR SPRINKLES. THEN...WE START TO SEE THE GOOD SURGE
OF MOISTURE COMING IN DURING SATURDAY AFTERNOON...WITH THE MAJORITY
OF MOISTURE LOCATED IN THE 700-300 MB LAYER...AND SOME ENHANCED
MOISTURE REACHING DOWN TO 850 MB. AT THAT TIME...A WEAK WAVE MAY
MOVE OVER THE AREA TO HELP TRIGGER SOME ELEVATED CONVECTION.
ALSO...IF THERE IS ENOUGH CLEARING OVER THE MOUNTAINS TO ALLOW FOR
DAY-TIME HEATING INDUCED INSTABILITY...THAT WOULD ALSO HELP
THUNDERSTORMS/SHOWERS TO SPARK OVER THE MOUNTAINS AND DESERTS. WRF
SHOWS THE WINDS ALOFT BEING SOMEWHAT WEAK...WHICH MEANS THE
POSSIBILITY OF SLOW MOVING STORMS AND AN INCREASED FLASH FLOOD
THREAT FOR SATURDAY...BUT THE GFS INDICATES STRONGER WINDS ALOFT AND
FASTER MOVING STORMS. FOR SATURDAY NIGHT INTO SUNDAY MORNING...THE
NAM...WRF AND CANSAC WRF SHOW SCATTERED TO WIDESPREAD PRECIPITATION
OVER THE AREA WITH AN UPPER LEVEL WAVE MOVING OVER THE AREA FROM THE
SOUTH. THE MOISTURE ALSO REACHES THE SURFACE BY THIS TIME ACCORDING
TO MODEL CROSS-SECTIONS. GOING TO SUNDAY AFTERNOON...LOOKS LIKE SOME
OF THE UPPER LEVEL MOISTURE CLEARS OUT...WHICH COULD RESULT IN
BETTER CLEARING OF CLOUDS AND MORE SUNSHINE. THIS WOULD HELP ENHANCE
CHANCES FOR THUNDERSTORMS AND SHOWERS FOR THE MOUNTAINS AND DESERTS
THAT AFTERNOON AND EARLY EVENING...WITH SOUTHWESTERLY FLOW ALOFT
CONTINUING. WINDS ALOFT OF 15-20 KT SHOULD KEEP STORMS MOVING
QUICKLY ENOUGH FOR THERE NOT TO BE A BIG FLASH FLOOD THREAT...WITH
THE FRESH MOUNTAIN BURN SCARS BEING OF BIGGEST CONCERN. FOR
MONDAY...THERE WILL STILL BE ENOUGH MOISTURE AROUND TO PRODUCE A
CHANCE FOR THUNDERSTORMS AND SHOWERS OVER THE MOUNTAINS AND DESERTS
DURING THE AFTERNOON AND EARLY EVENING HOURS.
FOR SUNDAY AND MONDAY...THE CLOSENESS OF THE REMNANT LOW OF DOLORES
COULD CREATE AN OFFSHORE FLOW SCENARIO WHICH COULD HELP TO HEAT UP
THE AREAS WEST OF THE MOUNTAINS. THIS...IN ADDITION TO SURFACE
DEWPOINTS POSSIBLY RISING INTO THE THE UPPER 60S/LOW 70S FOR THE
COAST AND VALLEYS...WILL RESULT IN HOT AND MUGGY CONDITIONS
SUNDAY...AND MONDAY AS WELL. FINALLY...ALL THE MOISTURE IN THE MID-
TO-HIGH LEVELS MAY INHIBIT NIGHT AND MORNING MARINE LAYER LOW
STRATUS/FOG FORMATION...WITH PATCHY LOW CLOUDS AT BEST.
DRY CONDITIONS LOOK TO PREVAIL NEXT TUESDAY THROUGH FRIDAY UNDER
SOUTHWEST FLOW ALOFT AS THE RIDGE GETS NUDGED EAST BY A TROUGH ALONG
THE WEST COAST...WITH DAY-TIME HIGHS SEVERAL DEGREES BELOW NORMAL.
EXPECT THE NIGHT AND MORNING MARINE LAYER CLOUDS TO RETURN FOR THE
COAST AND PORTIONS OF THE VALLEYS.
&&
.AVIATION...
172030Z...COAST/VALLEYS...VFR CONDITIONS THROUGH THIS EVENING.
PATCHY STRATUS...WITH BASES FROM 1500-1800 FT MSL AND TOPS TO 2500
FT MSL...WILL DEVELOP ALONG THE COAST/VALLEYS TONIGHT. HIGH/MID
CLOUDS MOVING INTO THE REGION TONIGHT THROUGH SATURDAY WILL HELP
MAKE THE LOW CLOUDS MORE PATCHY. SHRA/TSRA WILL BEGIN TO DEVELOP
ACROSS THE AREA LATE TOMORROW MORNING AND CONTINUE THROUGH THE END
OF THE WEEKEND. FORECASTER CONFIDENCE IN CLOUD FORECAST IS MODERATE
TO HIGH.
MTNS/DESERTS...MOSTLY CLEAR WITH UNRESTRICTED VIS THROUGH THIS
EVENING. INCREASING MID/HIGH CLOUDS LATE THIS EVENING THROUGH
SATURDAY MORNING. OCCASIONAL WESTERLY WIND GUSTS TO 40 KT WILL
CREATE MOSTLY MDT UDDFS AND LLWS OVER AND EAST OF THE MTNS...MAINLY
THIS AFTN AND EVENING. CHANCE OF SHRA/TSRA SATURDAY LATE MORNING
THROUGH THE END OF THE WEEKEND.
&&
.MARINE...
130 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH THIS
EVENING. CHANCE OF THUNDERSTORMS SATURDAY THROUGH SUNDAY OVER THE
COASTAL WATERS. GUSTY AND ERRATIC WINDS...CLOUD-TO-WATER LIGHTNING
AND ROUGH SEAS MAY ACCOMPANY ANY THUNDERSTORMS. CONDITIONS WILL
IMPROVE BY SUNDAY NIGHT.
&&
.BEACHES...
130 PM...A 5 FT/11 SEC SOUTHERLY SWELL FROM TROPICAL CYCLONE DOLORES
WILL REACH PARTS OF ORANGE COUNTY AND NORTHERN SAN DIEGO COUNTY
SATURDAY INTO SUNDAY. ELEVATED SURF OF 5 TO 7 FT...WITH ISOLATED
SETS TO 8 FT...WILL BE LIKELY ALONG SOUTH FACING BEACHES OF ORANGE
COUNTY AND NORTHERN SAN DIEGO COUNTY. STRONG RIP CURRENTS ARE
EXPECTED THROUGH THE WEEKEND.
ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE SATURDAY THROUGH
SUNDAY AT THE BEACHES. LIGHTNING...GUSTY AND ERRATIC WINDS...AND
HEAVY DOWNPOURS ARE POSSIBLE WHERE STORMS DEVELOP. A BEACH HAZARDS
STATEMENT IS IN EFFECT THROUGH THE PERIOD.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...BEACH HAZARDS STATEMENT FROM LATE TONIGHT THROUGH MONDAY EVENING
FOR ORANGE COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL
AREAS.
PZ...NONE.
&&
PUBLIC...HARRISON
AVIATION/MARINE/BEACHES...JJTThe San Diego radar (KNKX), 28 km away, was scanning. The volume nearest the first event began at 00:43 UTC.
12 flash flood, 9 lightning, 7 debris flow, 5 thunderstorm wind, 2 funnel cloud, 1 dust storm. Local standard time, as filed.
A large area of blowing dust from a thunderstorm downburst was reported over the Deserts of San Diego County.
An trained spotter estimated a 60 mph wind gust just southeast of Borrego Springs.
Thunderstorm winds knocked over and tree, which blocked the east bound lanes at 66th Ave. and Harrison St. in the town of Valerie.
The CHP reported a hard closure of roadways near the intersection of Jackson St. and 66th Ave. due to roadway flooding.
CHP reported transformer struck by lightning.
CHP and local media reported a small brush fire started by lightning.
CHP reported a lightning started brush fire at the intersection of Interstate 215 and Harley Knox Blvd.
Small brush fire from a lightning strike reported by CHP.
CHP reported a small brush fire started by a lightning strike.
CHP reported a small lightning ignited fire near Keller Peak.
CHP reported a lightning fire near the intersection of Dillon Rd. and Fargo Canyon Rd. northeast of Indio.
CHP reported multiple palm trees on fire due to a lightning strike near the intersection of Jackson St. and 61st Ave.
CHP reported traffic signals lights knocked out by a lightning strike.
Six large pine trees downed by strong winds near Porto Ct. The largest tree was close to 3 feet in diameter.
The CHP reported a vehicle almost submerged in water on one of the on-ramps at the intersection of Highway 163 and Interstate 8 near mission valley.
The CHP reported a stalled tour bus being struck by a rock slide. No injuries occurred but the bus was disabled.
CHP reported Chihuahua Valley Rd. closed due to flooding.
CHP reported a bent electrical pole with wires hanging across the roadway in Nuevo.
CHP reported vehicles stranded in water at the intersection of Interstate 5 and Genesee on-ramp.
The CHP reported a mud and rock slide at the intersection of State Route 78 near Wynola Rd. and a trained spotter reported a debris flow on Banner Grade at mile marker 61.
The CHP reported multiple vehicles stalled in flooded waters on the off-ramp from Fletcher Parkway to Interstate 8. Multiple vehicles were also submerged in flood waters along Alvarado Road.
CHP reported significant urban flooding in the Moreno Valley area due to a heavy line of thunderstorms. The most significant flooding was reported at the intersection of Interstate 215 and Van Buren Blvd, where 8 cars were stuck in high waters. In Reche Canyon residents were unable to leave their homes due to flooded roadways. Portions of State Highway 60 were also impassable.
A trained spotter reported a funnel cloud over Lake Elsinore.
CHP reported a downed palm tree blocking the roadway.
CHP reported a mud and rock slide blocking both lanes of Old Julian Highway.
Training thunderstorms produce heavy rainfall over Ramona with 0.58 in falling between 1401 and 1419 PST. The CHP reported significant flooding and road closures along 11th St. in Ramona, that the road was completely washed out at the intersection of State Route 78 and Ramona View Dr., and water washing fences and debris over Vista Ramona Rd. A trained spotter reported water 3 ft deep at Ramona Rd. and Lawrence St. with some residents unable to evacuate their homes.
CHP reported a roadway covered in mud at Cajalco Rd. and La Sierra Ave.
CHP reported significant flooding along State Route 91. Vehicles were reported to be stuck in flood waters at the intersections of State Route 91 and Van Buren Blvd., and State Route 91 and Adams St. Mud covered all lanes at the the Central Ave. intersection.
A funnel cloud formed and dissipated in less than one minute.
Orange County Fire reported that a portion of Silverado Canyon Rd. was temporarily closed, with up to 3 ft of mud across the roadway.
CHP reported the roadway getting washed away at Lone Pine Canyon Rd. near East Canyon Dr. around 0345 PST. A spotter also reported significant flow through the normally dry Sheep Creek Wash, with lots of tree trunks going by.
CHP reported mud flowing across all lanes with lanes blocked on Interstate 15 near the Cajon Junction.
CHP reported a vehicle stuck in flood waters on the interchange between State Routes 71 and 91.
Spotter reported 1 to 2 feet of water across US-395 near Shadow Mountain Road.
Two swift water rescues were conducted along the Lytle Creek Wash.
Spotter reported that Mt. Baldy Rd. was closed at Falls Rd. due to rock/mud slides.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2015Every state in 2015This day in weather historyWarnings in California, July 2015
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: 597008, 596596, 596595, 596588, 596610, 596611, 596605, 596606, 596608, 596616, 596604, 596603, 596614, 596602, 596600, 596601, 596664, 596625, 597003, 596968, 597006, 596658, 596622, 596624, 597001, 596995, 596663, 596661, 596620, 597022, 596640, 596643, 596662, 596639, 596646, 596645.