Well, I’ll start this update off with an apology. In my last update, I wrote about a major pattern change that would essentially mark the end of our 100-degree days for the season. In fact, I’ll even directly quote myself:
“This shouldn’t even lead you to believe that we won’t hit 90 again at some point this year, but it’s looking rather unlikely that we’ll have another strong heatwave.”
Boy, was I wrong. Almost immediately after posting that update the weather models began to do a complete 180 turn, going away from below average temperatures and toward yet another strong heat wave. My bad.
So, with that, let’s talk about this heat wave! The National Weather Service issued an Excessive Heat Watch for much of the area. This is in effect for Wednesday and Thursday, when temperatures are expected to be the hottest. Here are the main points from the watch:
- Location: The entirety of my coverage area (Benton, Franklin, Walla Walla, Morrow, and Umatilla Counties), including the Blue Mountains.
- Temperatures: Highs 98-109 in the lowlands with 90-98 in the mountains. Lows will only reach into the 60s and 70s.
- Timing: Wednesday and Thursday, with the hottest periods being 10am to 8pm.
- Impacts: Heat-related illnesses possible, including with pets and livestock.
For those interested, the full text of the watch can be found at this link.
Even though the watch is only in effect for Wednesday and Thursday, those won’t be the only days above 100 this week. The ridge of high pressure responsible for this week’s heat wave is already building over the region. While I only have 97 in the forecast for Monday, there is a chance that some areas will reach 100. Those with the highest chance of breaking 100 are along the Columbia River from Boardman in the west to about Hat Rock in the east. This includes Hermiston.
Hazy skies are expected to persist through the duration of the week. This is because of the high-pressure system building over the region will create an inversion by essentially squashing all of the air it can down into the valleys and basins. With that air, of course, also comes smoke from wildfires as well as other pollutants such as those from vehicles.
It is important to note that areas with a thick layer of smoke overhead will experience cooler temperatures. Today’s Area Forecast Discussion from the NWS Pendleton states the following:
“The only thing that may prohibit temperatures from getting that hot is an increase in smoke in the atmosphere due to area wildfires, especially if they grow rapidly.”
Temperatures turn to the extreme side for Wednesday and Thursday. I went with highs (for the Tri-Cities) around 105-107 for those days, and the National Weather Service is currently even more conservative with highs around 103-105.
With that said, some models are projecting even higher temperatures. The GFS (shown above) is projecting highs around 110 on Thursday, but there are also some with lower temperatures. The GDPS (Environment Canada’s global model) only has us running around 105.
At any rate, whether it’s a high of 100, 105, or 110, it’s going to be hot. Please be aware of the symptoms that you or those around you are experiencing when you are engaging in activities outside. Remember that heat stroke is an emergency that warrants a call to 911. Also remember that what might be just fine for you could be too hot for someone with you (or vice versa).
If you notice any of the symptoms listed in the graphic above, please take appropriate action. For symptoms on the left side, move to a cooler place (or shade if no cooler place is available). For symptoms on the right, consider dialing 911 for further aid.
Stay cool out there, and thanks for reading! Frequent updates will continue to be provided over on my Facebook page – Tri-Cities Weather, and if anything big changes I’ll publish a full update here.
