Winter Weather Returns to the Sierra


Winter Weather Returns

 Our first winter storm of the season with significant amounts of rainfall and Sierra snowfall is poised to affect Northeast California and Western Nevada Sunday into Monday.   A Winter Weather Advisory has been issued for Sunday Evening into Monday for portions of the Sierra from the Tahoe Basin down to Mono County. (areas in the purple shading)


Link to view this map here


Incoming Moisture
This storm system will usher in a solid band of moisture off the Pacific Ocean and will provide healthy rainfall and high elevation snowfall totals to the region. The animation below shows a model depiction of this moisture band (orange and yellow shading).  


This will also coincide with the expected precipitation timing. Rainfall enters northern Lassen County Sunday morning then drops across the Tahoe Basin Sunday Evening and finally Mono County Monday morning. 

Rainfall & Snow Level:
An important note to take away from this storm: Snow levels will be high to start and the bulk of the precipitation will fall as rain. Only areas above 9,000 feet will see all snowfall from the start. 

Snow levels will crash to near 6,000 feet by Monday morning but the bulk of the moisture will have already passed. Monday morning will be the best time frame to see some snowfall at lower elevations but we are mainly looking at just a few inches at most at lake level. You can see the approximate snow level drop on the graphics below. (Can be found here, then click "Snow Level Forecasts")




Rainfall Amounts:
Heaviest rains near and south of the I-80 corridor.
  • Sierra Crest:  2 to 2.5 inches.  (liquid equivalent)
  • Tahoe Basin & areas west of U.S. 395:   1.0 to 1.5 inches
  • Western Nevada: 0.25 to 0.75+ inches. 



Snowfall Amounts:

Tahoe Basin: 
  • Above 8,500':    1+ feet
  • around 7,000':   3 to 5 inches (including Echo and Donner Summits)
  • Lake Level:        Generally less than 2 inches


Mono County: 
  • Sierra Crest above 9,000':    1 to 2 feet
  • around 7,000':   3 to 5 inches 


Impacts
  • Travel: As this is the first solid storm of the season, many may not be prepared for winter driving conditions. The highest Sierra passes (Tioga, Sonora, Carson, Mt. Rose) will see the heavier amounts of snow (1+ feet) with Echo/Donner summits seeing a few inches. 
  • Winds: Moderate, possibly blowing around Halloween decorations left unsecured. 
  • Cold: Tue-Thurs with widespread freezes each night. The coldest mornings are expected to be Wednesday and Thursday.

For additional forecast details see our Area Forecast Discussion. 








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