July 30, 2009

The Cooling

4 PM Update...the Hoquiam-Seattle pressure difference is now 3.8 mb. A strong onshore push is thus guaranteed. Put up your wind chimes. It is coming. If anyone is planning on hitting the water...particularly in sail boats...please be prepared and careful. The winds will pick up later and get quite gusty.

We had a minor intrusion of cooler air at low levels last night into the interior, but this thin veneer is rapidly getting mixing out...so temperatures will surge now back into the 90s...sorry. The coast is much cooler (60s). There should be a modest onshore push of marine air tonight...watch the difference in pressure between Hoquiam and Seattle...when it gets above 3-3.5 mb you know it is coming. The thermal trough should jump into eastern Washington with the push and temps tomorrow should only get into the mid to upper 80s. Hard to believe that 80s seem cool.

34 comments:

  1. I told a friend yesterday evening that "Oh, it's so gloriously cool outside now!" and he laughed at me - it was 88F!! I was astonished I felt so good (well, plus the sun was down - the evil evil sun). Guess it really is all relative.

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  2. Since it is so hot now, when the cool ocean air comes in, could we see a quick burst of sudden high winds like in early June? That was kind of fun... and would be wholly welcome in my sustained 88 degree 2nd floor sandwiched apartment!

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  3. Seems like SeaTac may not even hit 90 today. Only 86 at 1:50pm.

    It seems so much cooler today.

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  4. Spoke too soon. Less than an hour later and SeaTac hits 90. So the streak of 90+ days is intact.

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  5. Olympia and Portland are both around 90, Kelso is 81. I wonder if there is a mixing of air coming down the Columbia?

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  6. i'm wondering too about the predicted high and what it is now, during what ostensibly should be (?) the hottest part of the day (3pm): kuow said it's 84 now with high of 98 expected. tell me that it's too late for that to happen...??

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  7. Olga said "i'm wondering too about the predicted high and what it is now, during what ostensibly should be (?) the hottest part of the day (3pm)"

    This time of year the hottest part of the day is rather later.

    Take a look at the MOS predictions at the NWS and you can see the hour by hour predictions (though remember they're not always on the money).

    e.g. for a Seattle location the peak today is at 5pm

    http://forecast.weather.gov/MapClick.php?site=sew&smap=1&textField1=47.62180&textField2=-122.35030&FcstType=graphical

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  8. Kevin, or one could look at Seattle's NWS climate information at http://www.weather.gov/climate/
    index.php?wfo=sew and look at the times of high temperatures on past days to get an idea of when they usually occur. The last four days, for example, the high temperature of the day occurred at 5:35pm (Wednesday), 4:49pm (Tuesday), 5:03pm (Monday), and 4:48pm (Sunday). Of course, this lists the latest (I believe) time of occurrence if it reached the high more than once or stayed there for awhile.

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  9. 94 in the shade near Bitterlake in Seattle. It is ten degrees cooler than this time yesterday, although 94 is still really, really hot. But that said, the heat today heat does not seem as oppressive as yesterday.

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  10. At my house outside Bellingham it's 94 degrees. Meanwhile at Friday Harbor on San Juan Isl. it's an indicated 69 degrees.

    That's a 25 degree gradiant spread over about 25 miles.

    Maybe the long awaited push is on it's way?

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  11. The HQM-SEA pressure gradient is now at +3.2! That marine push can't get here soon enough.

    http://www.wrh.noaa.gov/zse/sea_gradients.php

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  12. A nine-degree drop at Everett in the last hour according to http://weather.noaa.gov/weather/current/KPAE.html (!)

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  13. I'm wondering how long this drought is going to last. The U.S. Drought Monitor suggests that we will have above normal temps through August and below normal precipitation through October. This confirms my gut feeling of what to expect, but I don't know how far ahead these things can be projected very accurately.

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  14. 94 in Lynnwood now, too. So, what are our chances of beating the old record for over-90-degree-days-in-a-row? I just checked at http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=&sid=KSEA&num=168&raw=0&dbn=m&banner=off and Seatac is up to at least 3 days, depending how y'all measure time...

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  15. Given that the updated forecast calls for temps in the mid-80s at the max, I think there's little chance that even Seatac will reach 90 on Friday.

    I'm not clear on how often probcast is updated. At present, it predicts 89 tomorrow for (my) zip code 98043, while the NWS has just 81. I'm guessing probcast's forecasted temp will go down when it's updated, but I'm real curious as to just how much it will differ from the 81.

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  16. A great graphical view into the barometric pressure changes could be found on wolframalpha.com:

    http://www88.wolframalpha.com/input/?i=seattle+and+hoquiam+barometric+pressure

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  17. Been watching that little cutoff low off the California coast. Seems to be stuck in a eddy. Be nice if it ejected north-probably will go into Southern Oregon though...

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  18. kevin and nicholas: thanks for the explanation and pointers to the NWS. i must've misheard NPR as 84 when they more likely said 94 (wishful thinking...). that would've been quite an increase for 2 hours.

    and now, to fire up the stove.

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  19. Any word on the time in the evening this marine push will occur ?I would like to go out to the beach and exprience it!

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  20. I`ve been noticing that upper level low as well and models are`nt quite sure where to swing it and when it will move inland, if it does at all. That is what I`m seeing.

    So.....no t-storms over the WA Cascades, but I see there are storms firng over the mountains in BC and over the Oregon Cascades. Cliff or anyone....how come no t-storms over the WA Cascades today like there was the past couple days?? Guess the airmass must not be to unstable over the higher terrain.

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  21. HQM-SEA pressure difference at 4.1MB now according to this helpful page. But WHEN will it reach Kirkland??? The leafy trees on the ridge behind our house are twitching a bit, but nothing down at ground level yet....

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  22. I know 90 is a round number, but something you probably haven't heard - the record for consecutive 89+ degree days in Seattle is 5 days, the same as the record for consecutive 90+ degree days. With Sunday's high of 89, today is the fifth straight day of 89+ in Seattle, tying that record. I know 89 isn't a nice round number, but if you think about it, 89 is just as arbitrary a number...

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  23. And the current observations for the central Sound aren't showing any real easterly wind flow yet. Sigh. READY FOR THE BREEZE!

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  24. how long does it take for the hot air to move over the mountains once the marine push starts?

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  25. It's here, I think! Temp dropped 5 degrees in the last 40 minutes. Wind has picked up. Temp dropping rapidly. Fabulous!

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  26. Not an official temperature but the weather station at Volunteer Park actually had it's maximum a little after 3pm (about 3:20pm). And has dropped by more than 10 degrees off the maximum now (at 7pm).

    THe mostly northerly win speed picked up this afternoon and I think that Sound Breeze is helping.

    http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KWASEATT110

    So that's a little earlier than I expected!.

    My apartment is cooling off rather more quickly than I expected too (it's still more than 91F!).

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  27. As recently as yesterday, NWS was predicting sunny and 70-ish for Ocean Shores for today. Instead, there was a high marine fog layer all day, never lifted, and I doubt it got up to 65 -- it was quite disappointing.

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  28. Schaz, ahhhh, sounds like paradise! Thanks for sharing!

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  29. 61 and light rain at Shelton at 9:21 this evening??

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  30. evidently
    SHELTON LGT RAIN 59 56 89 SW20G29 29.87S

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  31. I don't think that rain is real...a sensor malfunction. The wind blew something past the precip type sensor...

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  32. I wondered too, if it had, Danger Jim Foreman would of been there.

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  33. This comment has been removed by a blog administrator.

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  34. Snoqualmie...
    North side of house in vegetation, elevation approx 700 feet:
    102 degrees

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