A very wet storm system will be moving into our region on Wednesday, Dec. 18, 2019, bringing with it non-stop rain until Sunday.

We recommend everyone battens down their blue tarps, gets out the rake and clears storm drains, and drive carefully. If you live near a creek, perhaps get some sandbags ready as well.

“The big story with this system will be a LOT of rain in the lowlands and lower elevations the mountains and big time mountain snow,” Washington Weather Chasers said. “It is possible that double the amount of rain Seattle received the whole month of November will fall Wed.-Sat. (3”+.).”

The National Weather Service also issued this Hydrologic Outlook:

Hydrologic Outlook
National Weather Service Seattle WA
405 AM PST Tue Dec 17 2019

…HEAVY RAIN WILL LEAD TO RISES ON MANY RIVERS THIS WEEK…

A strong weather system will move into the region this week,
bringing heavy rainfall across much of Western Washington. The
heaviest rainfall will begin on later on Wednesday and continue
into the weekend. Generally, 3 to 6 inches of rain are expected
across the region, with the largest amounts focused in the
Olympics and Cascades.

Snow levels will begin around 3,000 feet but will rise
to around 5,500 feet by late Thursday into Friday. The timing of
the increase in snow levels, as well as the location where the
heaviest precipitation sets up, will impact the degree of flooding
at particular locations. Nonetheless, these rainfall amounts are
likely sufficient to lead to flooding impacts on several area
rivers by the weekend, and some of these impacts could be
widespread or significant.

Please continue to monitor the latest forecast through the week,
as the details of potential flooding will change as the situation
evolves.

WEATHER: Storm system with 'a LOT of rain' moving into area Wednesday 1

Here’s the 7-day forecast from the National Weather Service:

    • Tonight: A chance of showers between 10pm and 4am, then rain likely after 4am. Mostly cloudy, with a steady temperature around 43. South southeast wind 7 to 9 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
    • Wednesday: Rain. Steady temperature around 42. South wind around 14 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.
    • Wednesday Night: Rain. Low around 42. South wind 11 to 14 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
    • Thursday: Rain. High near 49. Southeast wind 7 to 10 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.
    • Thursday Night: Rain. Low around 45. Chance of precipitation is 100%. New precipitation amounts between 1 and 2 inches possible.
    • Friday: Rain. High near 50. Chance of precipitation is 100%.
    • Friday Night: Rain. Cloudy, with a low around 45.
    • Saturday: Rain. Cloudy, with a high near 47.
    • Saturday Night: Rain likely. Cloudy, with a low around 42.
    • Sunday: A chance of rain. Mostly cloudy, with a high near 46.
    • Sunday Night: A slight chance of rain. Mostly cloudy, with a low around 38.
    • Monday: A slight chance of rain. Mostly cloudy, with a high near 44.