Very icy and treacherous in the West Hills right now. We’ve had one news crew get stuck in the past hour up on Skyline Road, and reports of multiple cars off-road or in a collision near Barnes and Miller Road. Avoid hilltop areas the rest of the night!
The rest of this post is just technical talk, for basic highlights read the previous post…
It makes a lot more sense now. Especially now that the 4pm balloon sounding is done. Now we know exactly what the temperature profile is overhead, at least what it was at 4pm. What happened today was quite similar to what we see with a major marine push in summer, except that there was no push from the Coast to the Interior. Everything else was the same.
1. Top of the moist and cold air mass was around 2200′ this morning, as mentioned in the earlier post. But look at it on the 00z!
The inversion is now up around 6,000′. It’s not that the temperatures dropped in the lower layer, it’s just slightly warmer at 850mb (-3.7), but they warmed dramatically above. It’s 44 at 7,000′ this evening, it was 16 at the same time yesterday. That’s from the well exposed Palmer Lift base on Mt. Hood so it’s unrelated to terrain. So the moist layer west of the Cascades thickened, we had a strong west wind through the Gorge, gusts to 64 mph at Auspurger Mountain there. Then west of the Cascades waves of drizzle or light showers coming in from the northwest. Sound familiar? In today’s case, much of the “marine drizzle” was in the form of snow showers. All of .01″ measurable at PDX. All of this occurred in the cold air mass below 6,000′ while it was in the 40s above. Interesting isn’t it?
Chief Meteorologist Mark Nelsen