Smooth Move On The Heat Wave, Mother Nature...

SEATTLE - Tradition says that you celebrate 12-year anniversaries with silk or linen. But how do you celebrate the anniversary of our hottest day ever?

With...another hot day?

Today, July 20th, marks the 12 year anniversary of Seattle hitting 100 degrees -- the only time it's hit 100 in the history of Sea-Tac Airport.

(To be fair though, it did hit 100 on two other occasions back when the records were kept at the Downtown Federal Building. And to be exact, it technically only hit 99.9 on 7/20/94 -- so it has truly never hit 100 at Sea-Tac, but they round up.)

Anyway, we're not looking to topple the record this week -- or any of the high temperature records this week -- but a building heat wave promises to at least get temperatures in the neighborhood.

The heat wave gets its start today, as we get a double-whammy of sorts conspiring to make it hot around here.

Why So Hot?

First of all, a strong thermal trough beginning to build in. This is what pulls our winds in from the east, which not only holds our cool ocean seabreezes at bay, but also as that wind comes down the Cascade mountains, it compresses and gets even warmer.

Second, aside from the east-wind heating, a hot air mass is also pushing up from the Desert Southwest, giving the heat wave a little extra oomph.

How Hot Is It Now?

Check this image below for the latest current temperature, updated once an hour at roughly 10 minutes past:

If you don't see your city listed, you can try this link as well.

How Hot Are We Talking?

The heat wave is still building Thursday, so we're not at our maximum heat just yet. Highs today should reach the mid 80s in the Seattle area, and perhaps upper 80s away from the water and in the southwestern part of the state -- maybe low 90s toward Portland.

The really hot weather gets going on Friday, where we should reach the low 90s around the Puget Sound area, mid 90s along the Cascade foothills, and approaching 100 as you get down toward the Portland/Vancouver area.

Saturday looks like the peak of the heat wave, with temperatures a degree or three hotter than Friday. We're going 93 for Seattle.

An "Excessive Heat Watch" is in effect from Friday morning through Saturday evening, which basically means, hey, it's going to be hot.

We might get just a teensy bit cooler for Sunday, but it'll be hard to notice, with highs still right around 90 in Seattle, and 92-95 inland.

Is This Going To Break Any Records?

Obviously, our 100 degree mark is safe. The other records from this time of year are pretty lofty, and at this point, we'll likely get close, but not break any records. The record highs for Seattle are 100 today, then 94 on Friday, 95 on Saturday, and 99 on Sunday. It's possible we could get to 94 or 95 during this heat wave, but chances are low.

One "record" that we should at least tie, is pretty obscure. This will be the 5th consecutive weekend one or both days will have been 80 degrees or warmer. The last time that happened was in July and August of 1997.

Here's some other fancy hot weather tidbits, to point out that while long heat waves are rare, they can happen.

The record for consecutive days at 85 or hotter is 9 days, set twice (1977 and 1967.) The record for consecutive days at 90 or hotter is 5 days set in August 1981. Obviously we're not looking to get to these records, but if we somehow manage 4 days at 90 or better, that'd be second place.

On average, Seattle gets about 25 days a year that go over 80 degrees. 10 of those days will go over 85 degrees. Days that hit 90 or more are pretty rare, averaging just two per year, while a day over 95 occurs about once-every-other year.

This year, through July 19th, we've had 11 days at 80 or better, 6 days 85 or hotter, and just one day at 90 or hotter. It has not hit 95 in quite some time.

Want To Escape The Heat? Try The Coast

If you really, really, want to avoid 90-degree weather, you can try heading to Newfoundland, or perhaps just take a drive over to the Washington Coast. It'll still be pretty toasty over there Friday and Saturday, but probably moreso low-mid 80s than 90s, with the exception of Forks, which gets that same compressional heating scenario outlined above, only off the Olympic Mountains instead. So they are still a good bet to perhaps hit 90 or better. The San Juan Islands and Whidbey Island also tend to be somewhat cooler.

The coast also gets the cooling first when the thermal trough moves inland and the heat wave begins to end. So Sunday will be considerably cooler there -- perhaps 15-20 degrees cooler than inland areas. It's possible some of that cooling could get there Saturday evening -- especially the south coast since the thermal trough moves south to north.

I'm Stuck Here. What Can I Do To Stay Cool?

You've heard the usual ones: drink plenty of water, limit outdoor activity, don't leave pets or kids in the car, where it can get over 120 degrees.

But I've got a few tips I've tried when it gets really hot… especially for those who do not have air conditioning.

Don't use the stove. Plan dinners that maybe use the microwave, the outdoor grill, or just simple things like sandwiches. Or go out. Using the oven will only make your home hotter.

Don't use the dryer. Same theory as above. If you have a yard or can dry your clothes outdoors, that would work. Heat waves in the Northwest are a desert heat, so with the dry air, the water should evaporate in no time.

Keep the lights off. Unless you're using those fancy fluorescent lights, regular light bulbs also give off a decent amount of heat.

Keep a water spray bottle handy. If I'm feeling particularly hot, I spray my face and arms with a water bottle, then go stand in front of a fan. If you're going to the M's games this weekend, which are unfortunately day games on Saturday and Sunday, maybe bring an empty spray bottle, and then fill it with water once you get to the stadium (since you can't bring any liquids into Safeco Field.) Just be sure not to spray your seatmates…although they might ask to borrow it!

(Got any other staying-cool tips? E-mail them to me at scotts@komotv.com, and I'll add in some of the best suggestions.)

Also, remember that if you do leave your windows open at night, to use a dowel or some sort of security measure to keep the window from opening all the way -- especially on lower floors.

How Long Does This Heat Last?

While the coast should begin to cool down Saturday night and Sunday, it'll probably take until Sunday night for that thermal trough to move to our east and for some of that marine air to make it into the inland I-5 corridor areas.

But even though with the thermal trough gone and with it, those heating easterly winds, the air mass will still be quite warm. So even with a little bit of our marine winds returning, we're still expecting above-normal temperatures for early next week, but moreso upper 70s and low 80s as opposed to the 90s.

In the meantime, happy anniversary, 100 degree day. We'll toast with some ice cream or something :)