Winter Storm Warning
URGENT – WINTER WEATHER MESSAGE
National Weather Service SAN DIEGO CA
529 AM PST Mon Jan 25 2021

CAZ055-252300-
/O.CON.KSGX.WS.W.0001.000000T0000Z-210126T0600Z/
San Bernardino County Mountains-
Including the cities of Crestline, Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, and Wrightwood
529 AM PST Mon Jan 25 2021

…WINTER STORM WARNING REMAINS IN EFFECT UNTIL 10 PM PST THIS
EVENING…

* WHAT…Heavy snow occurring. Plan on difficult travel
conditions, including during the morning commute. Damage to
trees and power lines is possible. Additional snow accumulations
of 3 to 6 inches above 4000 feet with 6 to 12 inches above 5000
feet with isolated amounts up to 18 inches, are expected.

* WHERE…Heaviest snowfall above 4500 feet.

* WHEN…Until 10 PM today.

* ADDITIONAL DETAILS…Be prepared for significant reductions in
visibility at times. Snow is expected to impact travel at times
along Interstate 15 through the Cajon Pass.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency.

For road condition information in California…enter
8 0 0 4 2 7 7 6 2 3 if inside california or
9 1 6 4 5 5 7 6 2 3 if outside California.

Active Weather Alerts

WINTER STORM WARNING
ISSUED: 5:30 AM JAN. 25, 2021 – NATIONAL WEATHER SERVICE
...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 10 PM PST THIS
EVENING...

* WHAT...Heavy snow occurring. Plan on difficult travel
conditions, including during the morning commute. Damage to
trees and power lines is possible. Additional snow accumulations
of 3 to 6 inches above 4000 feet with 6 to 12 inches above 5000
feet with isolated amounts up to 18 inches, are expected.

* WHERE...Heaviest snowfall above 4500 feet.

* WHEN...Until 10 PM today.

* ADDITIONAL DETAILS...Be prepared for significant reductions in
visibility at times. Snow is expected to impact travel at times
along Interstate 15 through the Cajon Pass.


FIRE WEATHER OUTLOOK

FORECAST AND TRENDS

SNOWFALL REPORTS...

        STATION            SNOW(IN)  ELEVATION(FT)  LAST UPDATED

        TWIN PEAKS         11-13         5700       0130 AM SUN
        WRIGHTWOOD          11.5         6200       0130 AM SUN
        CEDARPINES PARK       10         5200       0100 AM SUN
        GREEN VALLEY LAKE     10         7000       1000 PM SAT
        LAKE ARROWHEAD      8-10      5200-5500     1000 PM SAT
        BIG BEAR RESORTS     5-8       7200-8400    0530 PM SAT
        ARROWBEAR             8          6200       0700 PM SAT
        BIRCH HILL PALOMAR    5          5700       0450 PM SAT
        MOONRIDGE             5          7400       0530 PM SAT
        BIG BEAR CITY        4-6         6800       0530 PM SAT
        SNOW VALLEY          3-4       7000-8200    0800 AM SAT
        HESPERIA             2-3         3500       0100 AM SUN
        PALOMAR MTN           2          4710       0430 PM SAT
        JULIAN                2          4200       0600 PM SAT
        FERN VALLEY           1          5590       0130 PM SAT
        APPLE VALLEY        0.5          3000       1200 AM SUN
SAN BERNARDINO COUNTY MOUNTAINS...

ID      STATION                PRECIP(IN)    ELEVATION(FT)

LTLC1   LYTLE CREEK RAWS          1.04         2790
MFLC1   MIDDLE FK LYTLE CREEK     0.76         3740
PPOC1   PANORAMA POINT            0.47*        3887
SDSWP   SNOW PEAK                 0.43 *       7865
CKCC1   CITY CREEK RANGER STA     0.43         2647
SWYC1   STRAWBERRY CREEK          0.43         2986
SDCRT   CRESTLINE                 0.35 *       5100
MTBC1   MT BALDY                  0.35*        4300
CRR1    PAIVIKA RIDGE             0.35*        5298
MZTC1   MANZANITA FLATS           0.34*        3920
BYCC1   BAILEY CANYON             0.31         3388
OKKC1   OAK CREEK CANYON          0.20         3676
DECC1   DEER CREEK DAM            0.19         2917
EEPC1   DEEP CREEK                0.19*        4839
SDARN   LAKE ARROWHEAD N          0.15 *       5180
BPFC1   BIG PINE FLAT RAWS        0.14*        6908
CVEC1   CONVERSE RAWS             0.13*        5200
BBLC1   BIG BEAR LAKE             0.11*        6768
WWCC1   WILDWOOD CANYON           0.11         2946
OFRC1   OAK GLEN FIRE             0.08*        4664
FWSC1   FAWNSKIN RAWS             0.05*        6903
SDANW   LAKE ARROWHEAD NW         0.04 *       5450
NYNC1   CABLE CANYON              0.04*        5516
RWDC1   RAYWOOD FLATS             0.04*        7097
WRT1    WRIGHTWOOD                0.03*        5950
HBRC1   HEART BAR                 0.02*        6690
HHPC1   HEAPS PEAK RAWS           0.01*        6350
RUSC1   RUNNING SPRINGS FS        0.01*        6076

HYDROLOGY…
Spotty showers will break out this evening and consolidate along the
coastal slopes during the night. A strong cold front will follow,
expected to pass coastal areas around 4 AM PST. A solid band of
showers will accompany the front, with rain rates as high as two-to-
three tenths inch per hour. They will be moving at a good clip, so
excessive rainfall is unlikely. The snow level will plummet behind
the front from around 4000 feet to 2500-3500 feet. Heavy snow will
likely accumulate above 3500 feet in the mountains, while scattered
showers continue at times west of the mountains. A few of these
could be briefly heavy with small hail and thunder as the atmosphere
will be quite unstable. Local ponding of water and urban flooding is
possible near these heavier showers, and if they repeat (train) over
the same area, but the threat of flooding overall is low and any
runoff will be limited.

Precipitation estimates are currently for 1-2 inches liquid
equivalent in the mountains (mostly snow) and from one-third to
locally one inch west of the mountains. Once again the deserts
will see little, with amounts ranging from just a few hundredths
of an inch north and Coachella Valley, to locally one-third inch in
San Diego County.

Another storm system has the potential to bring more significant
precipitation to the region later in the week (late Thu/Fri), but
amounts of rainfall and timing are uncertain. This will be a much
warmer storm. Runoff potential will be greatly increased due
elevated atmospheric moisture availability, already moistened
ground, melting snow, and higher snow levels. Interested parties
should closely monitor the forecast over the next few days.

&&

.SKYWARN…
Skywarn activation will not be needed for today. Activation will
likely be needed for Monday for rain and snow reports, and other
significant weather impacts.

&&

.SGX WATCHES/WARNINGS/ADVISORIES…
CA…Winter Weather Advisory until 6 AM PST early this morning for
Riverside County Mountains-San Bernardino County Mountains-
San Diego County Mountains.

Winter Storm Watch from this evening through Monday evening for
Riverside County Mountains-San Bernardino County Mountains-
San Diego County Mountains.