
A cold front will cross the Great Lakes and Northeast U.S. through today with gusty winds and areas of rain showers. A strong atmospheric river is then expected to move into the Northwest by midweek bringing a threat for moderate to heavy rainfall and flooding, gusty winds, and mountain snows for parts of Washington, Oregon, northern California, and the Sierra Nevada. Read More >
Coverage is affected by many factors.
Read the Coverage Map Notes below to understand these factors on the state and individual maps.
The coverage statistics and maps are calculated using a computer model and station data, assuming ideal conditions. Actual coverage may be 5 to 10 percent below the computer-predicted coverage due to the following factors: