June 16, 2012

Feeling a bit tropical outside?

Seems a bit humid?   More like the East Coast in summer than our normally low relative humidity?

The dew points...a good measure of the moisture in the air...are quite high today, reaching into the lower to mid 60s right now (around 2 PM Saturday).

Here are the current dew points at some local stations--no lack of 60s!

And with temperature in the low 70s, the relative humidities are quite high, with plenty of locations above 80%:

No wondering I am sweating so much while I am working in my garden today!

Typical dew points around here in the spring and early summer are more typically in the mid 40s.   Lets illustrate with Olympia, where the dew point is now 63F. This plot shows the dew points for the past 12 weeks.  Today is highest, with one time in early June getting to 62.

 To be so warm, with lots of clouds, and such high humidity means only one thing....tropical or subtropical air has reached us.  To illustrate this, here is the vertically integrated water vapor in the atmosphere forecast to occur at 2 PM today (Saturday):

 You can see the "atmospheric river" of moisture approaching us from the southwest.  Tomato plants love this kind of weather.

Don't like warmth and high humidities?   No worry.  This tongue of warmth and moisture is only transitory and will head south of us tonight (map at 5 AM below):

Time to break the bad news to my tomato plants.


  1. You bet, Cliff. Tomato plants love the warmth. And they will miss it. But, at least the temps won't be dropping down to 40 degrees at night. I know tomato plants despise that....

  2. In the winter atmospheric rivers bring lots of rain. Why so little now? Too warm?

  3. Love this weather once in awhile. Reminds me of September 2010.

    BTW, thanks for keeping an archive of your blogs. Whenever I want to reconfirm any weather event over the past years, I check your page because I know you would have talked about it.

  4. I've been wondering for a while now if there were any local meteorologists that post interesting things about our local weather. I live in bellingham and it seems like im constantly looking up wondering what the heck is happening in the sky. Funny how I come across this blog, because I have been reading your book. The fog, drizzle, and clouds today were amazing. That inversion was pretty darn exciting here in town. Thanks for the enlightening post Cliff. I look forward to more...Omar D.

  5. I want to echo franzmador's question. If this was a Pineapple Express, where was the rain? I got only drizzle... And living in the convergence zone as I do, why didn't that warmish air produce thunder and lightning? Isn't that what warm moist air does when it get forced up?


  6. Hey Cliff-- have you checked the radiation levels here since the Japanese Nuclear reactor FUBAR? http://coastlinesproject.wordpress.com/2012/06/16/california-beaches-impacted-by-fukushima-buckeyballs/

  7. Ansel and Buddy,
    The interesting thing is that in the summer we can get atmospheric river-like currents of moisture, but because the winds are less and there is less uplift, one does not get the same heavy rain...cliff


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