May 9, 2024

First 80 Degree Day to End Week 7

By Joseph Renalds, Neve Lin, and Alec Weise

Good afternoon Huskies! After a week featuring consistent below average temps, this aggravating theme of weather will come to an end. Today the barometer will rise to a pleasing 74 or so degrees. This is a solid 10 degrees above average. This will be just the start of a significant warm up. As a ridge offshore continues to build in strength and the low level winds turn offshore today, the region will experience warmth more typical of June the next few days.  With 850mb temperatures soaring to around 14C tomorrow, Friday will be the peak of this warm up with region wide low-mid eighties expected. All is to say, be mindful of what layers you wear in the morning, because once noon hits, you won’t need them. Note: Last time we hit 80 F was week 3 of fall quarter.

The offshore flow is already starting above our heads right now as you can see in the cross section above SeaTac airport. The red lines show temperature and the blue things show wind direction. The latest readings are on the left side and you can see the easterly wind slightly above the surface.

This leads to compressional (adiabatic) warming as air descends on the west side of the mountains. This flow will be slightly inhibited tomorrow by a northerly wind component so it won’t get as warm as it otherwise could be were the set up slightly different. You can see the wind flowing south along our coast towards an area of low pressure known as a thermal trough off the coast of Oregon in this run of the UW-WRF model.

The warmest days are looking to be on Friday and Saturday with afternoon temperatures getting close to or over 80 degrees and overnight temperatures only getting down into the mid 50s. For Mother’s Day on Sunday it will still be warm, but we will cool down a bit to low 70s and clouds will make a return as the day progresses.

With the first major warm up of the season upon us, it is important to note that lakes and rivers in the area are still very cold and are dangerous to swim in. The water flowing into rivers comes from snowmelt, which makes the water fast moving and drastically cooler than the air around it. It is a sad reality that every year people end up needing to be rescued, or in the worst case scenario, dying as a result of hypothermia from the cold water. So while you are enjoying the warm weather in the water, make sure to stay safe.

Something else to watch out for over the next couple days is the night sky. In the last day or so, the sun has released multiple coronal mass ejections (CMEs). These CMEs are Earth directed with potentials for them to generate auroras visible into the mid-latitudes. If you thought the weather we forecast here could be finicky at times, know that space weather has many other challenges. That being said, we will have clear skies on Friday and Saturday night if you are interested in checking it out. However, being in the city provides another obstacle in the form of light pollution, so even with ideal conditions the auroras may be difficult to see without a camera capable of long light exposure.

We hope you are able to enjoy the warmth and remember to stay safe, Huskies. Have a great rest of your week!