PORTLAND, Ore. (KOIN) – We know how the story unfolded on Labor Day weekend last year: a strong wind leading to a vicious push to active wildfires in the region.
While drought conditions almost feel normal at this point — it isn’t — it is still informative to reach back and understand how those conditions didn’t do any favors. With Labor Day weekend approaching, the one year anniversary of the dangerous east winds and blooming wildfires is just about here.
We find ourselves in a situation that is equally as dry, and for most locations in Oregon, even worse than where we were last year.
DROUGHT CONDITIONS LEADING INTO LABOR DAY 2020
This is an archived map of the drought conditions about one year ago, right before the September wind event that fueled the extreme fires through the foothills of the Willamette Valley. Conditions at that time of the year were dry. The Willamette Valley had seen little rain for the summer months of July and August, which we will discuss below in more detail. You can see, that a mix of moderate and severe drought hampered the valley from Clackamas, Marion, and Linn counties south. There are some locations that were actually avoiding the drought at this time, that being the Wallowa mountains in the northeast quadrant of the state. This is an area, that in 2021, is dealing with ongoing active wildfires. It shows you that conditions are different from season to season and year to year.
Let’s pair the visual element of the drought with a chart. Below is another way to understand the drought conditions and what each color in the map truly means. When we start approaching these levels of severe drought, fire risk increases. That is one of the main topics under the “D2 – Severe Drought” category below. With conditions this dry, it takes a lot to set the ship back on course. This is especially the case in late August and early September, when we are not known for having much rain in the forecast. This means we are practically borrowing safe time, in hopes that nothing grows exponentially because we can’t depend on rain to help. This isn’t the type of drought you want to be experiencing when a strong wind comes in with active wildfires burning. As of early September of 2020, there were no locations that were dealing with an exceptional drought. I think it is also very important to note that many reservoirs and lakes are going to be dealing with stress from the drought conditions.
TRACKING AGGRESSIVE WIND
Wind pattern and speed were real concerns in the early afternoon of Labor Day 2020. It was already very obvious that the wind moving in from the Columbia Basin was fierce and disruptive. We had dust storms near Moses Lake, Washington and wildfires were showing signs of rapid growth from the satellite. It was clear that the dry conditions and the weather elements were not pairing well. The driest conditions were in Oregon, which means we didn’t have a full understanding yet of how the wind would impact the wildfires in whole.
BACK-TO-BACK DRY SUMMER MONTHS
Summer can be dry around here. We bring in the majority of our rain and clouds during the cooler seasons. You can expect that the summer going into last Labor Day, was likely dry. You would be correct if you were to think that. Scant amounts around areas of the Willamette Valley and foothills of the Cascades. You may be curious about how much rain the months approaching September may offer, and it’s about 1 inch of rain total for the two months., with about half an inch of rain in July and then again in August.
Leading into the month of September in Oregon, areas like Salem and nearby communities were again dealing with those aforementioned drought conditions. The month of July only brought in a trace of rain in the Salem area. August, nearly just as dry, coming in with 0.12 inches of rain. That isn’t even close to the hopeful one inch.
I also want to point out, that there wasn’t much rain in general towards the end of winter and through the spring months of 2020. The effort to build deteriorating drought conditions goes back to February. February is a month that leans closer to 4.50 inches of rain on average. The ball was dropped early in the year, but the back-to-back summer months really escalated the situation.
Lastly, I want to show you a photo from mid September, over in Woodburn, Oregon. Obviously, still very dry, appearing as if it is a fall afternoon. This was the time period where wildfire smoke trapped most of the valley and the urge for a cold front and rain was number one on just about all lists. Plenty of leaves on the ground too, making it feel more like a fall day. It’s likely that the lack of sunshine and also the dry conditions stressed out some varieties of trees early last year.
What is important to note, is that it wasn’t just the drought conditions that were to blame. A rather rare wind storm was more of the root cause of such a dangerous wildfire explosion in the Willamette Valley.
We will have more on this event, and all the pieces heading into the event next week. Chief Meteorologist Natasha Stenbock is going to break down the wind event and also offer up more of the weather story.