Updated Thursday 6:45 a.m.
What does ketchup have to do with the forecast the next few days?
A lot.
We all take that ketchup for granted when there's plenty left in the bottle, happily putting a soupy pile of it on your dinner plate to complement those french fries that just came out of the oven (or fryer if you're old school). But when that ketchup bottle is almost empty, we quickly convert to "ketchup conservationists". We try our best to save -- and savor -- those final few drops of tomato-ey goodness before the bottle goes into the recycle bin.
That's where we are today weather-wise. The sunny & mild weather is the ketchup, and since it's early September... our ketchup bottle is almost empty. Back in June, most of us took days like this for granted. We shouldn't do that today, because as we all know sunny days in the 70s are hard to come by for most of the fall & winter.
High pressure is building in for a two-day visit starting today, and we are already enjoying its impacts. Aside from a few areas of morning fog, it will be mostly sunny throughout the day Thursday. That sunshine, coupled with the lack of a cooling onshore flow, will warm us up into the upper 70s this afternoon. We'll even see some isolated 80 degree readings in the Cascade foothills and SW Washington today.
Friday will be equally as sunny & mild for most of Western Washington. The exception will be at the coast, where the push of cooler marine air will arrive tomorrow morning. Highs there will only be in the 60s, but up & down the I-5 corridor it will be the second straight day with blue sky and highs in the upper 70s.
Big changes are coming for the Labor Day holiday weekend (as that ketchup bottle is down to just a few drips). Upper-level low pressure muscles its way overhead and the push of marine air will surge all the way from the coast to the Cascades. This means Saturday will be a much cloudier and cooler day. Highs will only be in the mid 60s, and there will be some showers on/off throughout the day, too.
Sunday & Labor Day will not be washouts, but both days will feature scattered showers throughout the day. I wouldn't cancel any outdoor plans, but prepare yourself for cooler conditions as daytime temperatures will only be in the low to mid 60s. That's 10º below normal and more than 15º cooler than today.
Long-range forecast models are coming into better agreement for somewhat sunnier & milder weather by next Wednesday (kind of like using a spoon to get that last bit of ketchup out of the bottle), but it is too early to tell how long that will stick around. The government's 8-14 day outlook calls for "near normal" temperatures & precipitation for Western Washington, which isn't a bad thing for early-to-mid September.
Time to go get some french fries!
Make it a great day --
Paul Deanno, KOMO4 Meteorologist
www.twitter.com/PaulDeannoKOMO
