Portland NWS just issued a High Wind Warning for all areas west of the Cascades in NW Oregon and SW Washington at midday. This if for storm #3 of our current round of wet/windy systems. Here is the latest:
- Confidence is very high that the Oregon Coast will see a major windstorm Thursday midday-afternoon. Gusts 75-90 mph look likely out there. Today’s storm turned out a bit weaker than expected, but don’t let that lull you into a false sense of security if you live out there, tomorrow’s system is different.
- Confidence is also high that there will be gusty south wind late tomorrow afternoon and evening in the western valleys too. I’m confident that we’ll see gusts at least 35-50 mph. This is a pretty typical winter wind event here. Not a huge storm in that case, but enough to cause some trouble.
- Much lower confidence that we have a “big” windstorm coming to the inland valleys. There IS a high enough chance that the NWS pulled the trigger on a High Wind Warning. That means gusts 58+ mph. That would be a big deal and the strongest we’ve seen here since December 2006.
- Wind will be from the normal easterly direction much of the day tomorrow…nothing interesting will happen until after 2-3pm.
- Based on available info as of noon: In the valley, from Eugene to Longview, I’m forecasting a sudden increase in south wind during the mid-late afternoon hours in the valley. Southerly gusts 45-55mph. This is similar to what we saw in late October. Because of the leaves on the trees and the very wet ground at that time, PGE had 80,000 customers out at one time! I think the same speed right now wouldn’t do as much damage with no leaves, but still a pretty decent southerly windstorm.
The big question is whether the wind ramps up beyond that into “Big Windstorm” category. Models seem to have back-pedaled just a bit and some have turned a bit weaker in the past 12 hours.
All the morning model runs are in with a few changes.
1. The GFS is farther offshore, which would put 50mph gusts almost out of range for the metro area.
2. The ECMWF is also ever so slightly farther offshore, but not enough to make much of a forecast difference. It’s also SLIGHTLY weaker with inland wind.
3. The GEM has a perfect track with the low heading north to around Olympia…quite a pressure rise, but it’s also the slowest.
4. All models are filling the low after it passes the central Oregon coastline. Not a big deal, but I noticed it.
5. Timing is slower all around…by about 6 hours compared to 24 hours ago.
6. The 12z and 18z NAM still say gusts 30-35 mph at best. I ignored it. Our RPM is very weak as well. Strange since it’s based on the GFS.
In general the trend looks a bit weaker to me and I’m not sold that we have any sort of major windstorm coming for the valleys, thus the wide range in the peak gust forecast (45-60 mph). There are still 2 more main model runs before the event, including one before I’m on at 10pm tonight for our “big show”.
So the big story for right now is “wait and see” what changes in models for the next 12 hours, and GET READY FOR A BIG STORM on the Oregon Coast!
Chief Meteorologist Mark Nelsen