CALIFORNIA, USA — We knew going into Saturday that it was going to be a wet day. However, the atmospheric river and associated rainfall stalled out as it made landfall Saturday morning and has been very slow to taper off.
For this reason, areas across Northern California – from the Bay Area to the Sierra – have seen more rain than expected. This has led to some significant creek and river flooding, especially in the foothills and along the Cosumnes River from Michigan Bar to McConnell.
In addition, snow levels dropped early this morning and continued to drop throughout the daytime, reaching lake level hours earlier than data on Friday suggested. This has led to rapid snowfall accumulation for areas at and above lake level. Tahoe has already seen a couple of feet of snow and will likely finish with 3 feet or more!
As of Saturday night, Interstate 80 is closed from Colfax to the Nevada state line due to spinouts and whiteout conditions across Donner Summit. If you don't have to travel through the Sierra tonight, don't!
For New Year's Eve night, the rain and snow will slowly taper off from northwest to southeast. Some lingering showers are possible in the valley through about 11pm, though it's likely most of the valley will ring in the new year under mostly clear skies.
Snowfall will take a bit longer to come to an end in the Sierra, with lingering showers possible through the early overnight hours.
Sunday looks to be dry and sunny, with above average high temperatures in the mid to upper 50s, with a few areas potentially even climbing above 60 degrees! It'll be a good day for clean up and to assess flood damage, because more rain chances arrive beginning on Monday.
Speaking of flooding, just because the rain and snow stop, doesn't mean the waters will go down. It takes a while for water to come down the Sierra and filter out through the Delta. So areas along and west of I-5 are likely to see rivers crest Sunday or early Monday.
