A very cold and potent low pressure system approached southern California on the 30th with showers increasing through the day and night with a shot of very low-elevation snow. The brunt of the storm occurred during the night of the 30th and morning of the 31st.
Every event with a place to put it; 11 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.
A very cold and potent low pressure system approached southern California on the 30th with showers increasing through the day and night with a shot of very low-elevation snow. The brunt of the storm occurred during the night of the 30th and morning of the 31st. Snow levels dropped rapidly overnight down to 1500-2000 feet, with some light accumulations even down to 1000 feet. The southern Inland Empire was hardest hit with the unusually low snow, covering areas like Temecula, Lake Elsinore, and Wildomar, which caused issues all along Interstate 15 down through Valley Center. Several inches were also reported in Ranchita and Julian in San Diego County. Overall, the snow totals went as follows: 10 to 18 inches across Palomar Mountain to Julian, 6 to 9 inches from Warner Springs to Julian in San Diego County, 2 to 4 inches from Temecula to Wildomar and Lake Elsinore in the southern Inland Empire, and 4 to 8 inches across Highway 74 and Horsethief canyon in the Santa Ana Mountains. The snow resulted in several road closures, including Highway 74 and Highway 18, stranded vehicles and chain controls on the roads that remained open. Rainfall totals below the snow level generally ranged from .25-1.25 inches, with no significant flooding reported. Thunderstorms also occurred with the leading edge of the cold front from Oceanside and Carlsbad to La Mesa with hail up to one-half inch diameter. Strong winds also accompanied this system with several reports of damage. Most gusts were sub-warning criteria, though a few stations recorded gusts over 60 mph.
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 Dec 29, 9:50 PM PST, 4 hours 10 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
950 PM PST MON DEC 29 2014
.SYNOPSIS...
A COLD WINTER STORM WILL BRING SCATTERED SHOWERS AND LOW ELEVATION
SNOW TUESDAY AFTERNOON THROUGH WEDNESDAY. TRAVEL IN THE MOUNTAINS
MAY BE SLOWED BY PERIODS OF HEAVY SNOW. THE STORM EXITS WEDNESDAY
NIGHT AND WILL BE FOLLOWED BY COLD DAYS AND VERY COLD NIGHTS THROUGH
FRIDAY WHEN FROST ADVISORIES OR FREEZE WARNINGS WILL LIKELY BE
NEEDED. WARMER OVER THE WEEKEND WITH HIGH PRESSURE BUILDING ALOFT
AND WEAK OFFSHORE FLOW AT THE SURFACE.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AN ELONGATED POSITIVE TILT UPPER TROUGH EXTENDS FROM HUDSON BAY
CANADA SOUTHWESTWARD TO NORTHERN CALIFORNIA THIS EVENING. A POWERFUL
SHORTWAVE OVER OREGON WILL DIG SOUTH ACROSS NORCAL TONIGHT AND INTO
SOCAL TUESDAY EVENING...DRAGGING THE COLDEST AIRMASS OF THE YEAR
INTO SOUTHERN CALIFORNIA WEDNESDAY.
THE TROUGH EVOLVES INTO HIGH AMPLITUDE EAST-WEST ORIENTED WAVE OVER
CENTRAL CALIFORNIA TUESDAY. THE AIRMASS IS INITIALLY QUITE DRY DUE
TO ITS INSIDE TRACK...BUT INCREASING MOISTURE IN WESTERLY LOW LEVEL
FLOW WILL SLOWLY SATURATE THE BOUNDARY LAYER TO AROUND 8000 FEET
TUESDAY NIGHT. LIGHT SHOWERS TOMORROW MORNING WILL BECOME MORE
WIDESPREAD THROUGH EVENING AS THE UPPER LOW AND SURFACE COLD FRONT
NEAR. DESPITE THE LACK OF A DEEP MOISTURE CONNECTION...THE EXTREMELY
COLD NATURE OF THE AIRMASS AND THE STRONG UPPER DYNAMICS WILL WRING
OUT MOST OF THE AVAILABLE MOISTURE.
THE POSITION OF THE UPPER LOW FAVORS A LONGER STRETCH OF ONSHORE
FLOW AND GREATER PRECIPITATION CHANCES ACROSS SAN DIEGO AND
RIVERSIDE COUNTY MOUNTAINS TUESDAY NIGHT INTO WEDNESDAY MORNING.
PROJECTING SNOW TOTALS IN THE SAN BERNARDINO MTNS AND THE HIGH
DESERTS IS A BIT TRICKIER AS THE FLOW THERE SHIFTS NORTHEAST BEHIND
THE TROUGH. IT WILL DEPEND ON HOW MUCH WRAP AROUND MOISTURE MAKES TO
THE HIGH DESERTS AND NORTHERN SLOPES OF THE SAN BERNARDINO
MOUNTAINS. SNOW LEVELS PLUMMET FROM 4500 FEET TUESDAY EVENING TO
2000-3000 FEET WEDNESDAY MORNING...LOW ENOUGH FOR SNOW IN SOME OF
THE INLAND VALLEY AND FOOTHILL LOCATIONS. SNOW LEVEL MAY REACH AS
LOW AS 1000 FEET IN CONVECTIVE CELLS.
STRONG OFFSHORE WINDS WILL MAINLY IMPACT SAN BERNARDINO AND
RIVERSIDE COUNTIES TUESDAY NIGHT AND WEDNESDAY BEHIND THE TROUGH.
850 MB WINDS ARE NOW PROJECTED TO INCREASE TO 45-50 KTS AND A PERIOD
OF STRONG NORTH TO NORTHEAST WINDS IS LIKELY ACROSS THE SAN
BERNARDINO MOUNTAINS...THE INLAND EMPIRE AND THE SANTA ANA MOUNTAINS
DURING THIS TIME. SUSTAINED WINDS OF 20-30 MPH WILL GUSTS TO 50-60
MPH AT SOME LOCATIONS. WEDNESDAY WILL BE A VERY COLD DAY WITH
COASTAL HIGHS IN THE MID 50S AND VALLEY HIGHS IN THE UPPER 40S TO
LOW 50S. IRONICALLY...ONE OUR WARMEST YEARS ON RECORD WILL END ON A
COLD NOTE.
THE TROUGH SLOWLY FILLS AND MOVES EAST WEDNESDAY AFTERNOON AND
EVENING WITH SHOWERS ENDING FROM NORTH TO SOUTH. SHOWERS MAY LINGER
INTO WEDNESDAY NIGHT ACROSS SAN DIEGO COUNTY. A DRY AND VERY COLD
AIRMASS WILL BRING UNSEASONABLY COLD WEATHER FOR THE FIRST DAY OF
2015.
THE POST-STORM AIRMASS WILL BRING ITS OWN WEATHER ISSUES IN THE FORM
OF FROST AND FREEZING CONDITIONS. A COLD...DRY CONTINENTAL AIRMASS
SETTLES OVER THE SOUTHWEST WEDNESDAY NIGHT THROUGH FRIDAY. OVERNIGHT
LOWS WILL FALL INTO THE 30S IN THE COASTAL ZONES...AND INTO THE MID
20S TO MID 30S IN THE INLAND VALLEYS AND PARTS OF THE COACHELLA
VALLEY. AGRICULTURAL INTERESTS SHOULD PREPARE FOR SEVERAL VERY COLD
NIGHTS LATER THIS WEEK. FROST ADVISORIES AND/OR FREEZE WARNINGS WILL
LIKELY BE NEEDED.
THE SYSTEM SHIFTS EAST THURSDAY NIGHT AND FRIDAY. BUILDING HIGH
PRESSURE OVER THE WEEKEND WILL BRING WARMER DAYS OVER THE WEEKEND.
&&
.AVIATION...
300500Z...FEW/SCT LOW CLOUDS AND STRATUS WITH BASES 2500 FT MSL AND
TOPS 3000 FT MSL WILL CONTINUE TO DEVELOP OVER THE COASTAL AREAS
THROUGH 30/0900Z. AFT 30/0900Z BECOMING BKN/OVC AND SLOWLY DEEPENING
OVERNIGHT. FURTHER DEEPENING IS EXPECTED TUESDAY MORNING WITH
CHANCES OF LIGHT RAIN SHOWERS OVER AND WEST OF THE MOUNTAINS AFT
30/1500Z. CIGS DROPPING BELOW 2000 FT MSL IN SOME OF THE HEAVIER
SHOWERS WITH VIS DECREASING TO LESS THAN 5 SM. SNOW LEVEL FALLING TO
2000 FT MSL BY TUESDAY EVENING.
COACHELLA VALLEY....SKC THROUGH TUESDAY MORNING WITH MID AND LOWER
CLOUDS AOA 2500 FT FORMING ABOVE MOUNTAIN SLOPES BY 30/1800Z. A
GUSTY NORTH NORTHWEST WIND AND VCSH AFT 31/2100Z THROUGH TUESDAY
EVENING. SNOW LEVEL FALLING TO AROUND 2000 FT MSL BY TUESDAY
EVENING.
&&
.MARINE...
900 PM...WEST NORTHWEST WINDS WILL INCREASE LATE TUESDAY MORNING AND
CONTINUE THROUGH TUESDAY EVENING AHEAD OF A COLD WINTER STORM THAT
WILL BRING SCATTERED SHOWERS AND A CHANCE FOR THUNDERSTORMS LATE
TUESDAY INTO WEDNESDAY. HEAVY ICE PELLET SHOWERS AND ISOLATED
WATERSPOUTS ARE POSSIBLE WITH THUNDERSTORMS. ONSHORE FLOW WILL
INCREASE TO NEAR 15-20 KT LATE TUESDAY MORNING THROUGH TUESDAY
EVENING...BECOMING NORTH OVERNIGHT INTO WEDNESDAY MORNING. SPECIAL
MARINE ADVISORIES MAY BE NEEDED FOR THIS PERIOD FOR GUSTY WINDS AND
THUNDERSTORMS...SO BE ALERT TO CHANGING WEATHER CONDITIONS AND LATER
STATEMENTS.
&&
.SKYWARN...
SKYWARN ACTIVATION MAY BE REQUESTED TUESDAY NIGHT AND WEDNESDAY TO
FIELD REPORTS OF WINTER STORM IMPACTS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WINTER STORM WARNING FROM 4 PM TUESDAY TO 4 PM PST WEDNESDAY
ABOVE 2000 FEET FOR THE APPLE AND LUCERNE VALLEYS...
COACHELLA VALLEY...RIVERSIDE COUNTY MOUNTAINS...SAN
BERNARDINO COUNTY MOUNTAINS...SAN BERNARDINO AND RIVERSIDE
COUNTY VALLEYS-THE INLAND EMPIRE...SAN DIEGO COUNTY
DESERTS...SAN DIEGO COUNTY MOUNTAINS...SAN DIEGO COUNTY
VALLEYS...SANTA ANA MOUNTAINS AND FOOTHILLS.
PZ...NONE.
&&
PUBLIC...MOEDE
AVIATION/MARINE...JTThe national radar mosaic for the moment the first event began.
5 high wind, 3 winter storm, 3 heavy snow, 1 winter weather. Local standard time, as filed.
High winds occurred at the Whitewater RAWS between 0150-0350 PST on the 30th. During this time, winds were sustained out of the west-northwest at 35-40 mph with gusts in the upper 50s, including the peak gust of 59 mph recorded between 0250-0350 PST.
High winds occurred at the Mt. Laguna HPWREN mesonet between 0315-0515 PST on the 30th. During this time, winds were sustained out of the west-southwest at 45-55 mph with gusts in the low 60s. The peak gust of 63 mph was recorded between 0505-0515 PST.
A 24 hour snowfall of 2-8 inches was reported by the public near Idyllwild.
Between 2000 PST on the 30th and 0200 PST on the 31st, heavy snow combined with wind and cold stranding over 100 motorists along Highway 138 between Pilot Rock Road and Old Mill Road along the south side of Silverwood Lake and around Crestline. No major injuries were reported, but a huge impact on resources for the county and risk to the people while they were stranded. The highway was closed in this area as a result.
The public reported 24 hour snowfall totals as follows: 9-12 inches at Big Bear Mountain and Snow Summit, 8 inches at Green Valley Lake and Running Springs, 6 inches at Lake Arrowhead and Forrest Falls, and 5 inches in Crestline.
The Mt. Laguna Observatory reported a 24 hour snow total of 12 inches. The COOP observer at Mt. Laguna reported a 24-hour snow total of 8 inches. The COOP observer at the Palomar Mountain Observatory reported a 24-hour snow total of 14 inches. Multiple public reports of 7 to 9 inches of snow in Julian.
High winds occurred at the Fremont Canyon RAWS between 2051 PST on the 30th and 1051 PST on the 31st. During this time, winds were sustained out of the ENE at 35-55 mph with gusts in the 60s and 70s mph. A peak gust of 79 mph was recorded between 0451-0551 PST on the 31st.
CHP reported several inches of snow on Highway 74 in the Santa Ana Mountains resulted in closing both directions of the roadway between San Juan Capistrano and Lake Elsinore due to the heavy snow. An estimated 100 vehicles were stuck in the closure zone. There were also downed trees in roadway. A member of the public reported 6 inches of snow in 24 hours near Horsethief Canyon.
A spotter in the city of Orange recorded a wind gust of 58 mph. Another spotter in that area reported a wind gust of 46 mph with shingles blown off the neighbors roof.
A spotter just northwest of Lake Elsinore reported 6 inches of snow at 1400 feet causing widespread damage to trees with many limbs broken. CHP reported Interstate 15 impacted by snow with 1-2 at the Clinton Keith Road exit. The Baxter Road off-ramp was closed due to snow accumulations where cars are stuck in snow. Bundy Canyon Road off-ramp Was completely snowed in with several vehicles stuck in the snow. A spotter reported Interstate 15 shutdown at Wildomar with 8-10 inches estimated at elevation of 1400 ft. A member of the public reported a 24 hour snowfall of 5 inches reported near Lake Matthews.
A spotter in El Cariso Village reported 10 inches of snow as of 0800 PST with tree damage and power outages. The nearby El Cariso mesonet station recorded a wind gust of 44 mph between 1100-1115 PST on the 31st.
The Red Mountain HPWREN mesonet recorded high winds between 0606-0626 PST on the 31st with a peak gust of 62 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2014Every state in 2014This day in weather historyWarnings in California, December 2014
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: 553248, 553551, 553556, 553557, 553559, 553561, 553084, 553256, 553552, 553553, 553554, 553564.