Weather Synopsis for Wednesday & Thursday

We are in for another unseasonably warm and mostly sunny day with highs in the 50s and even a few 60s, but showers and thunderstorms will start to creep into the forecast along the west slopes of the Cascades and Olympics during the day. We should see scattered showers or isolated thunderstorms develop mid-day through the afternoon along the west slopes of the Cascades, but the main action will begin during the evening as a frontal system approaches the coast. The front will take advantage of other atmospheric conditions, like a relatively humid and unstable air mass to produce a widespread area of showers and potentially severe thunderstorms late this afternoon through the evening. Showers/thunderstorms should fire up first west of the Cascade crest this afternoon and move from south to north over the area.  The Passes and east slopes of the Cascades should see some of this activity as well, although it's unclear how far east of the crest the heavier showers/T-storms will push. Some thunderstorms may produce hail, and strong gusty winds. Make sure you're not caught out in these storms later today and tonight. 

Showers will become less intense later tonight as the front pushes through and we'll see a slow cooling trend.  A stacked upper low offshore will drift closer on Thursday, keeping showers in the forecast with low certainty on timing.  There will be a chance of afternoon thunderstorms on Thursday, but if they do develop, they'll be less intense than Wednesday evening.