PORTLAND, Ore. (KOIN) – Gear up for our first test run with colder air this week as temperatures start to fall by the weekend.
Monday afternoon is likely going to be the warmest part of the week before we start settling into cooler fall air by midweek. Still, we can’t escape the clouds moving in and out of the valley this afternoon. Most of the sunshine is setting up camp in central Oregon and for those to the east.
With this consistent flow from the northwest, we can’t rule out some clouds but very little rain should come out of this pattern. With that, there should be some nice moments of sunshine for your Monday. There is colder air and rain not too far away and that is what we are tracking this week.
This map gives us an idea of the temperature near the surface as of Monday around late morning. Do you see those blue dashed lines? That is representing locations where the temperature is at freezing or below. That cold air moved south quickly, bringing snow to areas like Iowa. (It’s not even Halloween yet!) Now it isn’t going to be that exact cold air that makes it here by the weekend, but we will have a taste of our own as a system drops south by Friday and cold air comes driving in from the Columbia Plateau.
By the way, if you don’t believe me about the snow in Iowa…check out this image. You can see the date right up on the top. It didn’t just snow…it S N O W E D. We haven’t even had that type of snow for our mountain passes yet. But it may be coming soon.
This is what the temperature will look like this week. Feast your eyes on Friday and Saturday. This is when we will really start to see some cold air move in. Not enough to end up in Iowa’s boat, but enough to see morning temperatures 30s and mountain snow. We have now reached the date where we typically do not see any more 70-degree days (Oct. 18). This week we will definitely not see any 70-degree days. If you haven’t taken out a jacket or potentially even some gloves, this may be the week to at least think about it.
Lastly, I like to give a visual of what exactly is going on. This is a graphic that is representing the temperature at around 5,000 feet. Weather models typically use Celsius when we are working with temperatures above the surface. This graphic is pushing in cold enough air to support snow below the mountain passes this weekend. Parkdale? It may be close. I believe the weather models are still trying to adapt to this cold air, but it does look like we will see a decent drop in temperature come Saturday. I would expect the models to find a common ground that is a bit warmer, but no doubt below average and enough to support snow for the mountain passes.
For those of you interested in the conversion of Celsius to Fahrenheit for the graphic above.