PORTLAND, Ore. (KOIN) – We start the new week with either a mix of sun and clouds or sun and wildfire smoke. Depending on where you’re at, you will experience one or the other, potentially both.
The visible satellite image below is delivering the story for us visually. We have a deck of clouds clasping to the Cascade foothills, with high levels of smoke streaming through south-central Oregon and points north. The clouds today will hang around portions of the Willamette Valley, with additional clouds floating in from the Pacific today. These clouds formed as temperatures dropped this morning, with a stronger onshore flow coming in from the ocean. These clouds are a sign that the trough is moving in and we are going to eliminate that summer heat from the weekend. You can get a lot of information from the type of clouds above your heads and in this case, it may be smoke.
How can you differentiate between the two? From a visible satellite standpoint, you can tell the difference due to the transparency and color of the wildfire smoke. All of the brown-tinted, transparent, veil-like product streaming through areas of Idaho, Nevada, Oregon and Washington is wildfire smoke. In some cases, you can see the source of the wildfire smoke down at the surface. The massive wildfires are streaming out smoke in plumes that are noticeable from space.
As far as the cloud coverage goes, you can pick that out due to the color and how dense it is. The thick deck of white over the Willamette Valley is cloud coverage. There is a small region in the southern Cascades near Medford where it is nearly a collision of clouds and wildfire smoke today.
If you cycle through the two smoke forecast models (one from the morning to get an idea of the context), you can see where the wildfire smoke is projected this evening. Some of the dense smoke clears out to the south, but an ongoing spurt of wildfire smoke is likely from our active wildfires in the Cascades today. I wouldn’t count on more wildfire smoke this evening. The wind is coming in from the west, which will keep the Willamette Valley clear of wildfire smoke, but not necessarily the clouds.
You know what we don’t need? We definitely don’t need any new wildfires. Unfortunately, conditions this afternoon and evening are ripe for rapid fire spread in the Lower Columbia Basin.
A Red Flag Warning or Fire Weather Warning is in place until 9 p.m. Monday for areas like Arlington and over to Pendleton. This is because of the incoming trough and the dry and breezy conditions that are picking up east of The Dalles.
I grabbed a quick tripcheck camera image coming out of that region this afternoon. A common view this time of the year, but it just appears dry from the eye. It’s hard to tell that it is windy, but conditions may gust to the 25 or 30 mph range this afternoon. Also, you can see the haze in the sky from the traveling wildfire smoke coming across the state from the local fires and areas to the north in Washington. This will expire tonight as conditions calm down and the relative humidity goes up as temperatures cool down after sunset. I don’t anticipate the warning to continue on Tuesday, because temperatures will be cooler.
Weather models have some regions of Wasco county and over in the warning area pushing the 35 to 40 mph range. This is the time of wind that can spread a fire quickly, which is the reason for the warning this afternoon. If you look at the wind gust weather model below, you can see areas of pink around the Cascades and then extending through portions of the Gorge. Not much of a wind gust for the Willamette Valley today, as conditions are mostly tame. This weather model is actually a depiction for late tonight, shortly after the warning is lifted. It is important to know, that even when the warning is lifted, that it still may be breezy out there.