What is going right now is quite amazing...summer and winter are within a half-mile of each other in much of the Pacific Northwest. Move a half mile and you can go from a maximum temperature in the mid-30s to the 60s or even near 70 (that is summer-like around here). The only detail is that this half-mile is in the vertical.
I have been looking at weather around here for a while, but this has to be one of the most extreme inversion cases I have ever seen. Take a look at the maximum temperatures yesterday in western Washington. High temperatures in the mid to lower 30s (even some 20s!) in the western lowlands, but 50s and 60s at observation locations around 2000-3000 ft. TWO stations in the hills southeast of Olympia got to 73 F. Yes, the 70s. Lots of locations in the Olympics were in the 60s.
Looking regionally, you can see this craziness extended into northern Oregon. Many 70s there. (not sure I believe the 85F reading!). Cold air is entrenched in the bowl of eastern Washington and warm temperatures (40s-50s) are found along the coast.
These startling contrast are associated with one of the strongest low-level inversions I can remember. Here are the observed temperatures above Seattle this morning. Above a cool layer near freezing that is roughly 200 m (600 ft) thick, there is a huge, sharp inversion, with a temperature change of 14C (TWENTY FIVE DEGREES F) in 400 meters (1300 ft). You read that right. Hard to believe.