Winter Storm Watch
URGENT – WINTER WEATHER MESSAGE
National Weather Service SAN DIEGO CA
334 AM PST Wed Jan 27 2021

CAZ055-272300-
/O.CON.KSGX.WS.A.0002.210128T2300Z-210129T2300Z/
San Bernardino County Mountains-
Including the cities of Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, and Wrightwood
334 AM PST Wed Jan 27 2021

…WINTER STORM WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON
THROUGH FRIDAY AFTERNOON ABOVE 5000 FEET…

* WHAT…Heavy snow possible. Travel will be very difficult to
impossible, including during the morning commute on Friday. Tree
branches could fall as well. Total snow accumulations of 4 to 8
inches above 5000 feet, 8 to 12 inches above 6000 feet and 12 to
24 inches above 7000 feet.

* WHERE…All areas above 5000 feet in the San Bernardino County
Mountains.

* WHEN…From Thursday afternoon through Friday afternoon.

* ADDITIONAL DETAILS…Significant reductions in visibility are
possible. Snow levels will rise to 5500 to 6000 feet Thursday
night, then fall to 4500 feet Friday.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts.

Active Weather Alerts
WINTER STORM WATCH
ISSUED: 3:35 AM JAN. 27, 2021 – NATIONAL WEATHER SERVICE
…WINTER STORM WATCH REMAINS IN EFFECT FROM THURSDAY AFTERNOON
THROUGH FRIDAY AFTERNOON ABOVE 5000 FEET…

* WHAT…Heavy snow possible. Travel will be very difficult to
impossible, including during the morning commute on Friday. Tree
branches could fall as well. Total snow accumulations of 4 to 8
inches above 5000 feet, 8 to 12 inches above 6000 feet and 12 to
24 inches above 7000 feet.

* WHERE…All areas above 5000 feet in the San Bernardino County
Mountains.

* WHEN…From Thursday afternoon through Friday afternoon.

* ADDITIONAL DETAILS…Significant reductions in visibility are
possible. Snow levels will rise to 5500 to 6000 feet Thursday
night, then fall to 4500 feet Friday.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts.



FIRE WEATHER OUTLOOK

FORECAST AND TRENDS

HYDROLOGY...
Lighter precipitation is not expected to extend eastward much past
Los Angeles County into early Thursday. For late in the day 
Thursday into Thursday night, precipitation will spread across 
southwestern California becoming heavy at times late Thursday 
night into Friday morning. Showers will continue Friday afternoon 
and end from the northwest Friday night. The slightly slower 
timing of the ECMWF and its ensemble members would have more 
substantial precipitation lingering into Friday evening, 
especially for San Diego County. There is a slight chance for 
thunderstorms for Thursday night and Friday.

An atmospheric river will be feeding moisture into the system as
it moves across the area Thursday night into Friday. Snow levels
will rise to 5500 to 6000 feet Thursday night, then fall to around
4500 feet Friday.

Rainfall is expected to range from around 1.5 inch near the coast
to 2 to 3 inches in the mountains with 3 to 5 inches on south 
facing slopes of the San Bernardino County mountains with locally 
greater amounts. High desert areas are expected to receive one 
half to one inch with one quarter to one half inch in the lower 
deserts. Snowfall of 4 to 8 inches is expected above 5000 feet, 8
to 12 inches above 6000 feet, and 12 to 24 inches above 7000 
feet.

Runoff is expected to be greater due to heavier rainfall on soils
saturated by recent precipitation. With higher snow levels, snow
melt will add to the runoff, especially in the San Bernardino
County mountains.