After a spell of drier weather, another atmospheric river is expected to stretch across California at the beginning of the week. This deluge of moisture will bring another bout of heavy rain to the lower regions and hefty snowfall to the higher terrain in the forthcoming days.
When energy is pumped into the Golden State, the start of the week will be turbulent with multiple rounds of snow predicted in the Sierra Nevada, the Klamath Mountains, and the southern Cascade Range. The most abundant snowfall is likely to take place at heights of 6,000 feet and higher, with the possibility of the snowfall being quantified in feet.
The snowfall will undoubtedly contribute to the risk of avalanches, as well as block travel routes due to road closures. Moreover, the amount of snow may exacerbate the probability of roof collapses and other structural damage to buildings.
Gusty southerly winds with speeds up to 45 mph may reduce visibility as they come into contact with snowfall in Northern California on Monday.
The northern and central parts of the state, in their lower elevations, will keep getting snow and rain. Residents in the San Francisco area should be aware of the possibility of flooding late on Monday and extending into Tuesday. Breaks in the precipitation are estimated for Monday afternoon, but people should remain on alert.
Locations in California that have experienced considerable precipitation in the past week will be most susceptible to flooding and road washouts due to the ground that has already been soaked from prior storms.
For the first three days of the work week, a zone north of San Francisco, from Santa Rosa to Redding, is expected to receive between 2 and 4 inches of rain. This precipitation is expected to reach coastal southwest Oregon and the greatest amounts will likely be seen in the Klamath Mountains and the Sierra Nevada foothills.
The majority of the rain is expected to occur late Monday and persist through Tuesday, since it is when the storm center is predicted to move onto land from the Pacific Ocean.
Forecasters are predicting that snow levels will increase on Monday up to 8,000 feet due to the warmer temperatures associated with the storm. An additional concern is the snow which has accumulated over the past week; its rapid melting could lead to a serious flooding hazard.
The Sierra Nevada is expected to experience the most accumulation; however, snowfall is limited to elevations of 8,000 feet and higher. This region's most extreme snow is predicted to begin Tuesday morning and cease by the evening.
This is the tenth atmospheric river the state has encountered this winter season, accompanied by two fatalities. U.S. President Joe Biden, in light of the continued storms in the West Coast, has consented to the request of an emergency declaration.
Will the state ever be able to take a breather from this weather? Forecasts predict that the middle of the week should be dry and certain areas in northern and central California will be met with some sunshine by Thursday as the clouds and wetness relocate away from the area.
California's dry weather will persist until the end of the week, while Oregon and Washington come under the influence of a weather maker by Thursday night. As the weekend approaches, Portland and Seattle will become the focus of an active weather pattern.