A pair of upper level lows brought showers and thunderstorms to Southern California from the 7th to the 11th. Though they were relatively small, the thunderstorms that formed were slow moving, allowing them to produce a few areas of flooding.
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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.
A pair of upper level lows brought showers and thunderstorms to Southern California from the 7th to the 11th. Though they were relatively small, the thunderstorms that formed were slow moving, allowing them to produce a few areas of flooding.
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 Apr 8, 2:01 PM PST, 2 hours 29 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 301 PM PDT FRI APR 8 2016 ...A STRONGER PACIFIC STORM SYSTEM ARRIVES LATE SATURDAY WITH THUNDERSTORMS/LOCALIZED HEAVY RAINFALL POSSIBLE... .SYNOPSIS... A MID/UPPER LEVEL LOW WHICH DELIVERED RAIN TO SOUTHERN CA THE PAST COUPLE OF DAYS WILL CONTINUE TO PUSH AWAY FROM THE AREA WITH LESSENING RAIN CHANCES THROUGH SATURDAY MORNING. HOWEVER...ANOTHER STRONGER PACIFIC STORM SYSTEM HAS EYES ON SOUTHERN CALIFORNIA AND ARRIVES BY SATURDAY NIGHT...MOVING SLOWLY ACROSS THE REGION THROUGH SUNDAY. THIS WILL BRING AN ACTIVE WEATHER PERIOD...PARTICULARLY SATURDAY NIGHT INTO SUNDAY. A WEAKER SYSTEM FOLLOWS IMMEDIATELY BEHIND THIS ON MONDAY...BUT WITH LIGHTER PRECIP FORECAST. RIDGING FINALLY BUILDS IN TUE-WED...PROMISING TRANQUIL WEATHER THEN. ANOTHER STORM SYSTEM DIVES SOUTHEAST ACROSS THE EPAC/WESTERN U.S. WITH POSITION/STRENGTH TOO UNCERTAIN TO DECIPHER WHETHER IT WILL BRING MORE RAIN TO THE AREA OR NOT AT THIS TIME. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... MID/UPPER LOW CENTER IS MOVING NORTH ACROSS NORTHWESTERN SAN BERNARDINO COUNTY AS OF THIS WRITING. THE BROAD ROTATION OF THIS LOW HAS BEEN CLEARLY DEFINED NOT ONLY IN MOVING SATELLITE IMAGERY...BUT ON RADAR LOOPS AS WELL. THIS SYSTEM WILL CONTINUE TO MOVE AWAY FROM THE AREA TONIGHT. DRYING WAS OCCURRING SOUTHWEST OF THE LOW. HAVE TRENDED POPS DOWN...AND UNLESS WE SEE MORE ACTIVITY DEVELOPING SOON OVER THE OCEAN...POPS MAY NEED TO BE LOWERED EVEN FURTHER. JUST DID NOT WANT TO GO TOO LOW AS ADDITIONAL SHOWER DEVELOPMENT COULD OCCUR. CERTAINLY NO WIDESPREAD RAINS ARE EXPECTED AS THE LOW AND ITS ASSOCIATED MOISTURE IS DEPARTING THE AREA. A BREAK IN THE ACTION TAKES PLACE TONIGHT-EARLY SATURDAY AS WE LIE IN BETWEEN WEATHER SYSTEMS. THE NEXT STRONGER PACIFIC LOW ARRIVES LATE SATURDAY. MODEL TRENDS HAVE BEEN SLOWER WITH THIS SYSTEM...DELAYING THE HEAVIEST PRECIP NOW UNTIL SATURDAY EVENING/NIGHT. HOWEVER...AS THIS LOW APPROACHES DURING THE DAY SATURDAY...MOISTURE WILL BE DRAWN IN AGAIN FROM THE SOUTHWEST WITH GFS/ECMWF SHOWING PRECIPITABLE WATER INCREASING INTO THE 1-1.1 INCH RANGE...VERY HIGH BY APRIL SOCAL STANDARDS. THIS COULD ALLOW FOR ISOLATED-SCATTERED SHOWERS TO DEVELOP. INSTABILITY WILL BE INCREASING WITH THE COLD CORE LOW MOVING IN LATE SATURDAY. HOWEVER...THERE WAS A SUBTLE SHIFT SOUTH ON THE 12Z MODEL RUNS...TAKING THE BRUNT OF THE ACTION INTO NORTHERN BAJA CALIFORNIA. HOWEVER...NOT HOLDING FIRM ON THAT SOLUTION...AND MODELS STILL SHOW DECENT QPF LOCALLY. INSTABILITY AND MOISTURE INCREASING ON SW FLOW AHEAD OF THIS COLD LOW SHOULD SET THE STAGE FOR AN ACTIVE PERIOD FOCUSING ON SATURDAY NIGHT NOW. CONCERN IS THERE FOR THUNDERSTORMS MOVING IN FROM THE PACIFIC OCEAN WITH LOCALLY HEAVY RAINFALL. ALSO...DEVELOPMENT OF LOCALIZED HEAVY RAIN/TSTORMS ON UPSLOPE FLOW OF PARTICULARLY THE EAST-WEST ORIENTED MOUNTAIN RANGES...NAMELY THE SAN BERNARDINOS. SEE HYDROLOGY SECTION BELOW FOR FORECAST RAIN/SNOW AMOUNTS. MOISTURE AND INSTABILITY WILL CONTINUE TO RESIDE OVER THE AREA INTO SUNDAY WITH A CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS. TSTORMS WILL POSE A RISK OF LIGHTNING STRIKES...HEAVY RAINFALL...SMALL HAIL AND EVEN A LOW POTENTIAL OF WATERSPOUTS. A WEAKER SYSTEM MOVES IN ON MONDAY WITH A CONTINUED CHANCE OF PRECIP...BUT WITH LESSER INTENSITY AND AMOUNTS. HIGH PRESSURE FINALLY BUILDS INTO SOUTHERN CALIFORNIA TUE-WED...ALLOWING FOR A DRY PERIOD TO TAKE HOLD...AT LEAST FOR A COUPLE OF DAYS...AND PERHAPS BEYOND. THE WEATHER PATTERN FOR LATE NEXT WEEK IS HIGHLY UNCERTAIN WITH REGARDS TO THE NEXT PACIFIC TROUGH COMING DOWN THE PIKE. GFS CONTINUES TO SHOW THIS TROUGH DIGGING SOUTH AND BRINGING ANOTHER ROUND OF ACTIVE WEATHER TO THE AREA NEXT THU-FRI. HOWEVER...THE ECMWF IS FLATTER WITH THE TROUGH/MORE PROGRESSIVE AND TO THE EAST...KEEPING THINGS DRY FOR LATE NEXT WEEK. HAVE NO CONFIDENCE IN EITHER ONE OF THESE SOLUTIONS AT THIS TIME...SO HAVE JUST LOW POPS THU-FRI. /GREGORIA && HYDROLOGY... HERE ARE THE FORECAST PRECIP AMOUNTS WITH THE SAT-SUN STORM SYSTEM. ...LOCALLY HIGHER AMOUNTS POSSIBLE... COASTS/INLAND VALLEYS...0.50 TO 0.75 INCHES MOUNTAINS...0.75 TO 1.50 INCHES HIGH DESERTS...0.25 TO 0.50 INCHES LOWER DESERTS...0.05 TO 0.25 INCHES SHOULD TSTORMS WITH INTENSE RAINFALL DEVELOP...URBAN/STREAM FLOODING COULD RESULT. A FLASH FLOOD WATCH IS NOT BEING ISSUED AT THIS TIME THOUGH...DUE TO LOW CONFIDENCE AND THE ANTICIPATED NON-WIDESPREAD NATURE OF ANY HEAVIER RAINFALL. THE SNOW LEVEL IS FORECAST TO BE RATHER HIGH...ABOVE 7000 FT. SEVERAL INCHES IS FORECAST BUT ONLY ON THE HIGHEST PEAKS HAVING LITTLE IMPACT...SO NO HEADLINES ARE ANTICIPATED. FORECAST PRECIP AMOUNTS FOR THE WEAKER MONDAY STORM SYSTEM ARE LESS THAN A QUARTER OF AN INCH...EXCEPT IN THE 0.25 TO 0.50 INCH RANGE IN THE SAN BERNARDINO AND RIVERSIDE MOUNTAINS. && .AVIATION... 082000Z...COAST/VALLEYS...SCATTERED SHOWERS WILL CONTINUE THROUGH SAT...WITH VARIABLE BKN/OVC CLOUDS WITH BASES 2000-5000 FT MSL...WITH AREAS OF 800-1900 FT MSL...AND LAYERED TO 20000 FT MSL. AREAS OF HIGHER TERRAIN WILL BE OBSCURED AT TIMES. LOCAL 2-4 MI VIS WILL OCCUR IN SHOWERS...AND AREAS OF FOG COULD DEVELOP IN THE VALLEYS 06Z-16Z SAT WITH LOCAL VIS BELOW 1 MI. MOUNTAINS/DESERTS...WIDESPREAD TERRAIN OBSCURATIONS AND AREAS OF MOUNTAIN VIS BELOW 1 MI IN CLOUDS/FOG/SHOWERS WILL CONTINUE THROUGH SAT. BKN/OVC CLOUD BASES WILL MOSTLY BE 3000-7000 FT MSL. CLOUDS WILL BE LAYERED TO 20000 FT MSL...WITH SCATTERED SHOWERS. ISOLATED THUNDERSTORMS ARE POSSIBLE THROUGH 01Z IN THE DESERTS. LOCAL VIS 2-4 MI WILL OCCUR IN SHOWERS OR THUNDERSTORMS IN THE DESERTS. LOCAL WEST SFC WINDS 20-30 KT WITH GUSTS TO 40 KT WILL OCCUR ON THE DESERT MOUNTAIN SLOPES 20Z-04Z THIS AFTERNOON/EVENING. && .MARINE... 100 PM...THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS WITH CLOUD- TO-WATER LIGHTNING...GUSTY AND ERRATIC WINDS...AND POSSIBLE WATERSPOUTS...FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON. WINDS WILL INCREASE TO 15-20 KNOTS FROM THE SOUTH SATURDAY...WITH A CHANCE OF HIGHER GUSTS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && PUBLIC...GREGORIA AVIATION/MARINE...MAXWELL
The Edwards AFB radar (KEYX), 55 km away, was scanning. The volume nearest the first event began at 00:31 UTC.
4 flood, 1 funnel cloud, 1 flash flood. Local standard time, as filed.
The CHP reported flooding on El mirage Road.
The CHP reported flooding on Highway 395 near Shadow Mountain Road. Vehicles were spinning out because of the water on the roadway.
A funnel cloud was reported northwest of the Perris Airport. The report received significant media coverage.
The southbound onramp of Interstate 15 was flooded with 1 to 2 feet of stagnant water. A BMW stalled due to flooded waters in the right lane.
The CHP reported several inches of water across all lanes of Highway 54.
The USACE and Bureau of Indian Affairs reported severe damage to Camino San Ignacio Road due high water and a debris flow. Areas upstream of the incident received moderate to heavy rainfall for approximately 3 hours. The damage to the roadway cut access to 15 homes. An application for a Presidential Declaration was filled for this event.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2016Every state in 2016This day in weather historyWarnings in California, April 2016
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: 628849, 628848, 628960, 628839, 628842, 628847.