Another powerful winter storm brought heavy rain and snow as well as strong winds to the areas. Overall, two to six inches of rain fell across the area.
Every event with a place to put it. 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 LOX wrote it up.
Another powerful winter storm brought heavy rain and snow as well as strong winds to the areas. Overall, two to six inches of rain fell across the area. This heavy rain resulted in flash flooding across southern Los Angeles county. In the mountains, strong southerly winds were reported as well as significant snowfall at the resort level.
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 Los Angeles, CA wrote its last area forecast discussion before the first event at Jan 22, 9:02 AM PST, 4 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
902 AM PST Sun Jan 22 2017
.SYNOPSIS...
There will be precipitation...heavy at times...and gusty winds into
this afternoon. This evening the rain will turn to showers...with
a chance of thunderstorms and gusty winds into Monday. There
may still be a chance of showers on Tuesday. The temperatures
should stay below normal into midweek. The skies will become fair
by midweek with normal temperatures on Friday and Saturday.
&&
.SHORT TERM...(TDY-TUE)
Rain is falling over most of the area with the exception of the
Antelope Valley area right now. Skies are mostly cloudy and there
are windy conditions above 2000 feet as well as along the SBA Co
central coast. One quarter to one half inch rainfall amounts in
the last six hours are common in SLO, SBA and VEN Co with a tenth
to a quarter inch in LA Co so far. Winds greater than 50mph along
I5 Grapevine also reported this morning.
*** From previous discussion ***
Satellite shows a textbook powerful winter storm with a cold low
to the west of Oregon with an occluded front wrapped around it and
extending into Oregon. From the occlusion a cold and a warm front
split off. The cold front extends from Modoc county to the Bay and
then out to the SW over the east Pac. Behind the front there is
plenty of convective open cell cu with a few lightning strikes.
The 06Z GFS and NAM runs remain in remarkably good agreement with each
other and are consistent with their previous runs. The forecast has
not been changed must at all. This will be the most significant storm
system for Southwestern California.
The heaviest rains associated with the main cold front will likely
affect SLO County between 5 AM and 1 PM, SBA County between 7 AM
and 3 PM, Ventura County between 9 AM and 5 PM and Los Angeles
County between 11 AM and 8 PM.
Just ahead of the front there will be a period of gusty se to s
winds across much of the region. Wind advisories have been expand
to include most all of the coastal and valley areas south of Point
Conception save for the San Gabriel. Gusty west winds behind the
front will likely affect coastal sections of LA/VTA Counties tonight.
The models do not show a great deal of instability with this
system. But there is a serious amount of jet energy and while the
chc of TSTMs is under 20 percent it is not zero either. There is a
better chc of TSTMs Monday.
Rain amounts will likely be 2-4 coast/valleys (highest near the
foothills), 3-6 foothills/mtns. Would not be surprised to see more
rain in the foothills above the city of Santa Barbara and the San
Gabriel Mtn Cstl Slopes. Peak hourly rainfall rates will be in
the 1-1.5" range (mainly south of Pt Conception due to the better
orographics)Rates this are capable of producing flash flooding
not only in the burn areas but across the entire forecast area
south of Pt Conception where a flash flood watch is in effect.
This is a special storm due to three factors. There is a 160-170kt
jet that will align itself parallel to the front which will slow
it down and intensify the from (rather than the usual
perpendicular jet to front orientation that shoots the front into
and through the area in just a few hours) This intense jet driven
storm will also be working with an impressive 1.2 to 1.4 inch
precipitable water column. Finally, a 8mb LAX to BFL onshore will
develop and this will bring very strong south sfc winds to the
area which will greatly enhance the rainfall on the south facing
slopes.
Snow levels will rise quickly to 8000 feet with the warm
southerly flow. They will then fall just as quickly this evening
in the wake of the cold front. Available moisture drops off
significantly but there will still be enough moisture to combine
with the colder air to generate decent snowfall amounts across
the mountains. A winter storm warning will go into effect just as
the high wind warning expires early this evening. Snow levels
will fall to between 4000 and 5000 ft by late tonight and continue
near there through Monday. These low snow levels will bring some
snow to the Grapevine but there will not be that much
accumulations.
Broad cold cyclonic flow will dominate the area on Monday. It will
be a showery day and the entire area will see some rainfall. The
rainfall with this storm will be much less homogeneous. The
atmosphere will be very unstable and there will be a slight chc of
TSTMs. These TSTMs will be able to put out some good rainfall
rates and another flash flood watch just for the burn areas may be
needed. It will be very cool day with highs mostly in the 50s at
lower elevations and 20s/30s in the mountains.
On Tuesday the upper low that is spinning off of the Oregon coast
will become incorporated into a large scale trof rotating out of
Canada. The latest mdls are taking this system further to the west
than previous runs and it looks like the best chc of rain will be
over the outer waters.
.LONG TERM...(WED-SAT)
Both the GFS and EC agree at least in principle that east pac
ridging will build into the area Wednesday and remain through at
least the weekend. While it will almost certainly be dry the mdls
do not show much in the way of warming due to the large sfc cold
pool. There will be some warming over the weekend as the ridge
increases and the offshore flow increases.
&&
.AVIATION...22/12Z.
At 07z at KLAX... there was no notable inversion.
Overall... Moderate confidence in the TAFs. The reduced confidence
is primarily due to the uncertainty in the timing of the storm.
MVFR conditions will continue to spread south and east with at
least MVFR conditions likely at all terminals by 19Z. IFR
conditions with a chance of LIFR conditions will develop around
the time of frontal passage. Gusty cross winds along with moderate
to strong wind shear and turbulence will spread south and east
through 02Z. There is a thirty percent chance of thunderstorms
after 08z.
KLAX... Moderate confidence in the TAFs. The reduced confidence
is primarily due to the uncertainty in the timing of the storm.
MVFR conditions will develop 13z-16Z with a seventy percent
chance of IFR conditions 20Z-01Z. East winds greater than 7 kts
will continue through 20z then shift to the southeast through 01z.
There is a forty percent chance of southerly cross winds greater
than 20 knots 22Z-02Z. There is a thirty percent chance of
thunderstorms after 08z.
KBUR... Moderate confidence in the TAFs. The reduced confidence
is primarily due to the uncertainty in the timing of the storm.
There is a seventy percent chance of IFR conditions 17Z-03Z.
There is a forty percent chance of southerly cross winds greater
than 20 knots 20Z-02Z. There is a thirty percent chance of
thunderstorms after 08z.
&&
.MARINE...22/300 AM.
Very dangerous sea conditions are expected today.
Breaking waves will continue over Morro Bay and Ventura Harbor
entrances as well as near the shoreline and breakwalls. There is
high confidence in a large swell through Tuesday but low
confidence on the timing of the swell heights.
High confidence for widespread gale force southerly winds and very
steep seas through midday for the northern waters and into the
evening for the southern waters. There is a thirty percent chance
that Gale Warning conditions across the southern waters may
continue into the overnight hours.
Moderate confidence in thunderstorms forming late tonight and
Monday.
&&
.BEACHES...21/900 PM.
A very large long period west to northwest swell will continue to
impact the region through at least Sunday. High surf warnings
reamin in effect through 6 am Sunday. Advisory level surf looks
likely through Tuesday night and possibly into Friday. Coastal
flood advisories also remain in effect through 9 am Sunday.
This is a dangerous situation for people near the surf zone.
Beach goers should use the highest level of caution during this
time. Much larger waves could wash over rocks, jetties and beach
areas near the water's edge, potentially sweeping you into the
water. West facing harbor entrances will be dangerous with large
breaking waves. Breaking waves may also occur in shallow water
near the outer edge of the surf zone.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 6 PM PST Tuesday for zones
34-35-39>41-87. (See LAXCFWLOX).
Wind Advisory in effect until noon PST today for zones
34>36-39. (See LAXNPWLOX).
Wind Advisory in effect until 3 PM PST this afternoon for
zones 37-38-40-41-44>46-51-87-88-547. (See LAXNPWLOX).
Flash Flood Watch in effect until 2 PM PST this afternoon for
zones 39-52. (See LAXFFALOX).
Flash Flood Watch in effect until 4 PM PST this afternoon for
zones 40-44-45-53. (See LAXFFALOX).
Flash Flood Watch in effect until 8 PM PST this evening for
zones 41-46-54-59-87-88-547. (See LAXFFALOX).
High Wind Warning in effect until 7 PM PST this evening for
zones 52>54-59. (See LAXNPWLOX).
Winter Storm Warning in effect from 7 PM this evening to 6 PM
PST Monday for zones 52>54. (See LAXWSWLOX).
PZ...Gale Warning in effect until noon PST today for zones
645-670-673. (See LAXMWWLOX).
Gale Warning in effect until 9 PM PST this evening for zones
650-655-676. (See LAXMWWLOX).
&&
.HAZARD POTENTIAL OUTLOOK...(TUE-SAT)
No significant hazards expected after Day 2. See the LOX
Watches/Warnings/Advisories for products concerning the current
storm.
&&
PUBLIC...ASR/jld
AVIATION...Kj
MARINE...Kj
BEACHES...Hall
SYNOPSIS...STU
weather.gov/losangelesThe Santa Ana Mts radar (KSOX), 53 km away, was scanning. The volume nearest the first event began at 22:36 UTC.
3 high wind, 1 flash flood, 1 winter storm, 1 funnel cloud. Local standard time, as filed.
Strong southerly winds developed across the mountains of Santa Barbara county. The RAWS sensor at Tepusquet reported a wind gust of 67 MPH.
Strong southerly winds developed across the mountains of Los Angeles county. Some peak wind gusts from the local RAWS stations include: Camp Nine (gusts 83 MPH) and Sandberg (gusts 60 MPH).
Strong southerly winds developed across the mountains of Ventura county. Peak wind gusts were between 60 and 65 MPH.
Flash flooding was reported at the intersection of the Pacific Coast Highway and Interstate 710.
A powerful winter storm brought heavy snow and gusty winds to the mountains of Los Angeles county. At the resort level, 24-36 inches of snow fell above 7000 feet. Wind gusts in excess of 50 MPH were reported.
A weather spotter reported a funnel cloud over Vandenberg Air Force Base.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2017Every state in 2017This day in weather historyWarnings in California, January 2017
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: 677811, 677809, 677810, 677808, 677812, 677814.