Funny how forecasts change like clothes around here. Late last week the models were showing a good chance for thunderstorms over western Oregon due to the cut-off low off the California coast. Latest models show only a chance of showers as that low tracks east/northeast. Typical forecast here. But, I am still holding out for something. As I was outside for lunch, I looked up to find a shortwave energy coming north through the valley. You can tell from its high cloud construction, as well altocumulus development.
So I decided to check out the satellite to see what patterns are emerging. If you look at the satellite animation from the NWS site, you’ll see the mid-upper flow over the Southern and Central Cascades is southerly. However, once that flow gets north to the border of Washington and Oregon you’ll see it diverge (see arrows). That’s an interesting feature, which corresponds to the cloud observation outside. If any conditions were to present itself for Thunderstorm formation, this would be a great start. Have to keep a close eye on this today, however I don’t think much is going to be likely. Dewpoint is at 54* right now, so not sure there’s going to be much to fuel anything west of the Cascades. Watch out over the mountains later though. Could see some good storms.
Your observations seem to be right on. However, I would add that after the heat wave it’s nice to be back in what appears to be a normal NW weather pattern. I’ll keep an eye on the sky and see what develops as the week progresses.
Posted by Bobby | August 4, 2009, 1:33 pmDepends on who’s happy about normalcy.
Posted by spinjunkey | August 4, 2009, 2:07 pmWhat a great day Wednesday is turning out to be. I know there were a few clouds this morning, but this afternoon the temperature is just right to enjoy the outdoors.
Everything is bit dry though, maybe some rain would green things up again. I know the weatherdude is looking for more than rain, he’d like some east coast type thunderstorms. I hope he gets his wish…
Posted by Bobby | August 5, 2009, 2:45 pmToo bad, the conditions changed too much and now no t-storms in the forecast. Although I heard mumblings about typhoon remnants coming our way.
Posted by spinjunkey | August 6, 2009, 6:58 amWell, it’s August 12 and still not thunder-boomers. At least we had rain and all the veggies perked up. Looks like the storms will hold off for a while here in the NW. We’ll just have to watch the rest of the US to see what develops.
Posted by Bobby | August 12, 2009, 7:13 pm