Extreme Rainfall in Northern California

Flash flood "high risk" forecasts are rare but they account for a greatly disproportionate number of flash flood deaths. 

The area Northern California outlined in purple has a high risk of flash flooding Thursday and Thursday night. It is a good time not to travel and to stay -- to the extent possible -- on higher ground. 

The area in red has a "moderate" risk of flash flooding tomorrow and tomorrow night. 

This is part of a larger area where flooding is possible the next seven days. 

Here's the forecast rainfall for the next seven days. 

Please note that, unlike the previous forecasts of the rain/snow from this "atmospheric river," the heavy rains extent south into the Sierra. There will be heavy snow in the higher elevations. 

Zooming out, here's the forecast precipitation through next Wednesday.

Please note that moderate to heavy forecast rains extend into the L.A. Basin.