The first full day of the summer season was a beauty in Puget Sound, with highs hitting the middle to upper 70s between Everett and Olympia. However, the skies looked very different over our mountainous terrain...

The daytime heating plus atmospheric instability combined to unleash afternoon thunderstorms over the Cascades and Olympics, complete with loads of lightning strikes near Snoqualmie Summit and Hurricane Ridge. Driving over the pass became dicey by Thursday evening as the big cells wandered right over I-90.

We'll hang onto a similar pattern for the next several days: quiet sunshine in the lowlands, but a chance for afternoon thunderstorms to blow up over the high country both on Friday and on into the weekend. If you have summer hiking plans for this first weekend of the season, you'll mainly enjoy comfortable temperatures and amazing views, but watch the skies for the chance of a quick stormy change each afternoon.

Otherwise, a string of days in the 70s near Seattle should make a perfect backdrop for playing tennis, swimming, or taking a spin on the two-wheeler. Enjoy!

Have a great night,
Shannon

Meteorologist Shannon O'Donnell
The KOMO 4-Cast Team

Updated Thursday Evening