WeatherWatcher: Significant rain and thunder showers possible Thursday afternoon through Friday

Significant rain and thunder showers possible Thursday afternoon through Friday.

We have a low pressure system that has been hanging out off the coast of Washington for most of this week giving us the showers and clouds and occasional thunder claps.

The big story is that low will be moving inland starting tomorrow and slowly moving through Friday and Saturday. Measure of instability called CAPE (Convective Available Potential Energy) is expected to be much higher than normal for this area.

The big general consensus points to major convection tomorrow generating large thunder cells that could produce downpours not unlike last Thursday's downpours that affected the Sea-Tac area, Edmonds, and Everett. These storm cells could cover the entire Puget Sound region.

Scene in Edmonds last Thursday. Note the overflowing manhole.
Photo by Carl Dinse

Be prepared for possible urban flooding, and rapid flooding. We could receive 2-4 inches of rain in the course of an hour with one of these storm cells. The nature will be hit and miss, so we may just be grazed by a storm cell and not receive any rain at all. Scattered heavy downpours are likely however so be careful, especially during the afternoon and evening commute on Thursday.

For up to the minute weather conditions and historic data, as well as links to weather information and resources, check out my page.

Follow me on Twitter: @SWeatherWatcher for any updates on weather events approaching our area.