PORTLAND, Ore. (KOIN) – We are just days out from what is going to be our next surge of dangerous and excessive heat. Now is the time to start preparing for that.
See if you can pick up an extra fan or spruce up the air conditioner with a new filter since each day will seemingly get a little warmer before it tops off on Thursday and Friday. We will have a forecast that likely changes by a few degrees as we assess the wildfire smoke situation as the winds shift out of the south later in the week.
For now, you have at least one more day where the heat is going to remain harnessed. The heat wave is going to likely start more on Wednesday, continuing into Saturday. Before we get to that forecast, you may be wondering if we are starting to get near the end of this type of heat for the summer. Well August is vulnerable to these type of stretches, but we are getting closer and closer to September, which tends to be a strict cutoff from triple-digit days.
The latest 100-degree day on record in Portland comes on Sept. 5, 1944, with a reading of 101 degrees. We’ve had some warm days in the 90s after that, but we don’t seem to find triple-digit heat after early September. We are less than a month away from that date, which means we are nearing the back edge of our summer heat. Will this be the year that we end up breaking that record? It’s unlikely, but we have found multiple patterns this summer that have allowed for some serious heat.
Also, an interesting thought for the summer, will we break the most 100-degree days? We’ve had a few years that we have had at least five days where we recorded 100 degrees or more. We can go back to 1977 for the most recent. We are currently at three, with this week coming, it’s possible we end up with five or potentially more.
Right now, we are going to be awfully close to hitting 100 on Wednesday and then again on Saturday. Those are the two days coming off the axis of the ridge of high pressure which is going to be a full-strength on Thursday and Friday. It is likely that we hit 100 degrees in that window of time. There will not be a drastic cool down with this heat wave, for we will build into it, and slowly fall out of that window over time.
With that information, be prepared for at least two to three days of triple-digit heat in the valley, gorge, and central and eastern sections of the state. The Oregon coast will be warmest on Thursday, but it will still hold the cooler Pacific Ocean air, with temperatures in the lower 70s. If you need to find relief, your best bet is going to be the coast. Of course, we know with this heat comes some major impacts on our daily routine. If you spend multiple hours outdoors, you absolutely need to find breaks. Finding shade and drinking a lot of water, while taking breaks indoors, is highly recommended. It is also a good idea to make sure you get your hard strenuous work finished before noon, as temperatures start to really flourish in the afternoon and early evening.
The National Weather Service in Portland has issued an Excessive Heat Watch for Wednesday through Saturday because of the severity of the heat coming in. There may be other weather alerts related to the heat as we near the event midweek. We know that those two days near the end of the week are going to be bringing the most aggressive temperatures, but again, the days on the outside are just as dangerous in the upper 90s. I want to note that the overnight temperatures are going to be warm. We may not drop under 70 degrees on Thursday morning or Friday morning. This is going to make it tough to cool down your houses as temperatures flourish in the afternoon under a full sky of sunshine.
I want to share an idea of what the heat is going to look like on Thursday through one of our weather models. It very nearly makes it out to the Oregon coast, in fact, some central Oregon coast communities may have temperatures pushing into the upper 70s. This may update, but the wind is mostly coming out of the west, which is fairly calm at this hour. The heat is pressuring areas of the valley and through the Gorge all afternoon. An east wind is trying to fin da way through the eastern Gorge, but it does seem to change directions around Hood River county or once it hits the mountains. We can gauge the forecast in the next 24 hours to see if there are some subtle changes.