PORTLAND, Ore. (KOIN) – We will take a dive into the cold pool of air again on Wednesday with below-average temperatures — highs in the 60s. Morning temperatures will hover in the mid-50s, with a few isolated spots cooler in the southern Willamette Valley.
This is the time to get your itch for a flannel shirt out, before it turns back to that summer heat. Not much of a difference in the morning from the Oregon coast to the valley. Not much of a range between the two in the afternoon as well. Maybe a good 5 to 8 degrees warmer than the coast.
It is a nice week to hit the trails or jump on the bike if you want to avoid the strength of a sunny day or the heat of summer. Just be ready for spotty showers in the afternoon if you do plan to be outside for extended periods on Wednesday.
We’re not worrying much about heat right now. There are a few locations that are bit warmer than others and that is the Lower Columbia Gorge Basin. From Yakima to Pendleton, the temperatures will be warmer than the rest of the two states, with highs topping off in the lower 70s to the mid 70s Wednesday afternoon.
Thinking about a road trip over to Pendleton? You’ll be able to put the windows down once you reach The Dalles. It should be a pleasant day, just outside the rain threat that will impact your neighbors to the south.
As long as this trough is perched over the Pacific Northwest (PNW), we are going to be battling a couple unsettled moments. One thing to note is that the eastern half the state is farther out of the core of the trough, allowing for warmer temperatures. Embedded into this trough is a blip of energy and another blip of energy. Those will enhance shower development for portions of the state Wednesday.
Rain will stay mainly east of the Cascades, with a few showers possibly sprouting up around the valley. If you look at the future radar below, there are downpours and thunderstorms forming in central Oregon by the late afternoon and early evening hours. They will travel from south up to the north, bringing moments of heavy rain.
These type of storms may also ignite some lightning, which could ultimately cause a wildfire. As we discussed above, with the rain moving through, the temperatures won’t warm all that much for areas like Bend and Madras. Temperatures warmer closer to the I-84 corridor and north through Washington for communities like Pendleton and Hermiston.
With those thunderstorms and downpours expected in Deschutes and Jefferson counties, you can expect the rain totals to be a bit higher than other parts of Oregon Wednesday. Weather models are actually going with a quarter inch in Bend. Keep in mind that it will be hit or miss with rain totals, as it will greatly depend on the development of those cells forming and where they end up traveling.
There is a high probability that those downpours set up there in the area of green in the graphic below. I would like to point out that even with the isolated showers west of the Cascades, we may find some miniscule rain totals around Portland too.