Some rather strong thunderstorms (by Puget Sound standards) formed off the Cascade mountains late Sunday evening and drifted into the Puget Sound lowlands.
Reports of frequent lightning and hail were plenty across Pierce, King and Kitsap Counties with one particular lyintense cell that passed over Graham and just east of Tacoma brought marble sized hail along as well.
The storms not only lit up the skies, but Twitter and Facebook too.
From @debbarker12: "It was incredibly bright & loud in the Graham area for over 40 minutes."
And from @kevinfreitas: "Loudest hail ever! Sounded like someone was walking with a metal ladder banging it against everything. #Tacoma"
Finally, from @ryankallio: "Harry Potter flew out of last thunderbolt."
Thunderstorms are rare in the Northwest -- particularly of this intensity, but we can blame the desert for this round.
The upper air flow pattern is coming from the due south, and that tapped into some monsoonal moisture from the desert and pushed it north into the Pacific Northwest. For the Puget Sound region, it was just one round of cells, but the shows have been much more intense in Central Washington.
Mountain thunderstorms remain possible through Monday with an outside chance one could drift into the lowlands once again, but by Tuesday all thunderstorm chances end in Western Washington.