PORTLAND, Ore. (KOIN) – We don’t want to put on our skis here, but it will feel more like an early summer day on Thursday, as temperatures can peak into the 70s around the valley for a day.
If we happen to be in the upper 70s or near 80s, it’s more like a late June or early July temperature. Of course, it’s spring, so you know it’s not going to last and we’re going to be on a roller coaster this week.
First, Portland is going to bask under blue skies with a few thin clouds for the next two afternoons. We are already enjoying this sun on Wednesday. A building high pressure ridge will act like a broom, sweeping away all heavy cloud interference. You can see a thin veil of cloud, but not enough to obstruct the view. The ridge axis will be directly overhead on Thursday, moving slightly eastward during the day. A strong southerly wind will cross the valley, with an easterly breeze near the West Gorge and Portland.
This type of ridge is one that would take our summer temperatures into uncomfortable territory. When it’s here in the spring, it puts us in a great place (over here). The ridge is wide enough to impact everyone in the Pacific Northwest (PNW). Temperatures will be well above average for the coast, valley and anything to the east. Get ready for a spring day you may not want to end.
Portland is expected to peak in the mid-60s on Wednesday. It will jump another 10 degrees on Thursday. It is possible that we mix up to the upper 70s. There is a layer of warm air above our heads, due to this aforementioned ridge, which is going to help increase the daytime highs around the valley.
Here’s the deal we’re making: we’re going to be warm for one day, but then sacrifice the weekend to the cold. We haven’t made the deal, but it’s happening. Follow the temperature trend below, it will take you to the lower 50s by Saturday. You can expect a drop of more than 20 degrees from the high temperatures on Thursday and the high temperatures over the weekend. It’s because that ridge isn’t going to hang around that long. What will follow is the opposite, low pressure and cold air.
For now, we’re soaking up all the heat here across the west coast. You will notice that the temperature departure from Vancouver south to Los Angeles is well into the red (warmer). This is exactly where this ridge settles. Meanwhile, there is a trough of cold air to the east that will keep temperatures from getting much warmer east of the Rockies. Weather models predict temperatures around the lower 90s for Sacramento and are even pushing into the triple digits for Bakersfield. This minimizes the temperature around Portland, since we have to take other parameters into account. The boost of wind should help lift our temperatures above the lower 70s. Anyway, you can see we’ve got some pretty hot weather here today.
JHERE ARE SOME BIG CHANGES END OF WEEKEND/START OF WEEK
We will quickly abandon this taste of summer. By the weekend, a large expanding trough will track southward bringing cold continental polar air from the north. With a paired low trying to collide with the Oregon Coast on Monday, we expect rain and light snow levels.
As discussed above, temperatures are going to be well below average and even flirt with the upper 40s for a few days this weekend. Snow levels are expected to drop to 1,000 feet and likely below by Monday morning. It’s good enough to bring a return of snow for the foothills of the region.
You’ll want to protect your vulnerable plants and flowers this weekend; however, the probability of snow on the valley floor is low. Is it possible for snowflakes in the area to mix with the rain? It may be possible.
We will be monitoring this system heading into the weekend. Just be ready to ride the roller coaster up and down this week.