Weather Update From US National Weather Service Reno Nevada:
The active weather continues to roll into the region. After the past series of relatively minor winter storms, we can expect wetter systems to move into the Sierra as an Atmospheric River becomes directed towards the west coast. This will begin later Sunday afternoon and could continue through Tuesday. Several pulses of energy will allow for periods of heavy snow in the higher Sierra with rain, initially, for lower valleys. Right now, snow levels are projected to begin around 7000 feet, but should drop to Lake Tahoe level early Monday. More uncertain but still possible, snow levels could fall as low as 4000 feet Monday into Tuesday allowing for some snow along the Sierra Front.
Confidence is high that there will be significant moisture beginning Sunday afternoon and evening, but there is some uncertainty about the strength and timing of individual pulses. There could be some breaks in precipitation; confidence is low for the timing of these at this point. All said and done, this moisture could tally up to multiple feet of snow above 7000 feet and some minor river rises. Totals will vary more widely below 7000 feet and will be very dependent on when snow levels drop. Currently projections show up to a foot in the Tahoe Basin, but expect these totals to change as details become more defined. Confidence is very low considering snow and rain totals for Western Nevada due to extremely variable model signatures. Hopefully these variances will begin to resolve themselves over the next day or so. The bottom line: expect significant travel impacts over Sierra passes with long delays heading into the end of the holiday weekend.