The heavens declare the glory of God;
the skies proclaim the work of his hands.
-Psalm 19:1

Do you know that God controls the clouds and makes his lightning flash?
-Job 37:15

Friday, April 18, 2008

Drawing in the sky

It was so funny this morning to walk out of my garage and see this in the sky, right before my eyes. Mini-Dew said, "X marks the spot." Indeed, the spot where my Sky Watch Friday shot would be taken. The contrails formed a clear "X" in the sky just north of my house this morning. It was very cool. Plus... in a bed of wafty cirrus clouds, even cooler. It looks like God took chalk to the sky.... In order to participate in Sky Watch Friday, please visit Tom's blog for details.

Contrails or vapour trails are condensation trails and artificial cirrus clouds made by the exhaust of aircraft engines or wingtip vortices which precipitate a stream of tiny ice crystals in moist, frigid upper air. Being composed of water, the visible white streams are not air pollution. ~Wikipedia
That being said, it might still interest you to know in which atmospheric conditions contrails will be generated... glad you asked... lol
What is key to the formation of contrails is atmospheric conditions. Contrail formation is dependent upon the temperature, relative humidity, and pressure at which the vehicle is flying as well as the ratio of moisture to heat produced by the vehicle's engine. In particular, the ambient air must be at low temperature and low vapor pressure. Vapor pressure is the pressure of water vapor within the atmosphere.

The ambient air mixes with the hot, humid exhaust because of turbulence generated by the exhaust flow. If that mixture happens to be saturated or supersaturated with moisture, a contrail will form. Answer by Jeff Scott.
Onto the weather... the SPC was accurate yesterday in forecasting a severe weather event; golf ball and baseball-sized hail fell yesterday in the plains. Today, that storm has mostly lined out to a squall event, and the severe weather is expected to occur in southern Louisiana and Mississippi. Aside from that, there was an earthquake yesterday in Illinois that registered a magnitude of 5.4 on the Richter Scale. Finally, we have Typhoon Neoguri, still a Typoon Category 2 with 100mph winds. Having lost some intensity overnight, it appears to be building back up just in time for a powerful landfall well east of the initial trajectory, now headed straight for Hong Kong, where a dear friend of mine lives.

I have some very sad news to share today. A dear friend of mine's brother was diagnosed with bone cancer one week ago Wednesday, when his pre-op for back surgery revealed spots on X-ray. The back surgery was to treat back pain which was most likely associated with the cancer, unbeknownst to anyone. The day before yesterday, one week after diagnosis, her brother passed away, after a painful battle. For many years, I have worked as a volunteer for the American Cancer Society raising funds during our annual Relay for Life event. For the past 3 years, I have served as the area accounting chair for the event. Stories such as this break my heart. Cancer is still destroying lives. There is still so much more research that needs to be done to eradicate this demonic killer. I have included a link for you to help support me in this vicious battle. Thanks for your support.

Enjoy your weekend!


  1. That's a wonderful shot. I always wonder who mans the switch at air traffic control when I see these!

  2. That's a terrific contrail. Not often will I see an X, especially one so nicely formed!
    I love your description of it. Very nice.
    Have a good weekend.
    Rocky Mountain Retreat

  3. How cool is that!
    Great Skywatch!

  4. Great.
    You've explained about my Sky Watch Friday on April 4th. contrails.
    Just now I've got the right noum!!!
    Luiz Ramos

  5. XXXX -cellent.. and great info..

  6. X marks the spot, too cool. I am truely sorry for your friends brother my heart and prayers go out to there faimly.God has taken another child home.
    So are you going on another adventure this weekend? You are so blessed to have so much fun! May I add you are a great blogger too, I know I have said it a kajillon times but You are just so good at it! kudos to you also for putting a smile on Jeff's face with the book interview! have a great weekend!

  7. Very cool picture! I love cirrus clouds. They can form some of the most intersting patterns in the sky. In other news for me, I had a mini chase here in Ft. Worth last night. I have an account with a couple of pictures up in case you are interested. Have a great weekend!

  8. I'm with you Sandy. This one seemed like a close call. lol

    Thanks, Michele. I had never seen a contrail X before. I thought it was bloggerific. You have a great weekend, too.

    Carletta, THANKS!

    Luiz, Glad I could identify yours for you. Any sky, cloud, weather questions you ever have, I would be happy to help you out with.

    Tom, Thank you, sir. Thanks for hosting, and thank you for working so hard to keep it fun.

    Jess, Thank you, thank you, thank you. No adventure this weekend, unless you count trying to have a yard sale in the rain... lol. I am very blessed to have so many adventures. I thank God every day. I hope you have a great weekend as well.

    Ken, Thanks. I love cirrus too. I will check out your chase account in a few. Lucky you. Have a terrific weekend.

  9. Dewdrop: This was a beautiful photo with great information. The music was on the spot marked with an X.

  10. My daughter loves contrails! She is always commenting on them. :o) With great excitement I might add.

  11. Thanks, fishing guy.

    Beth Ellen, I remember loving contrails as a child. I loved it when the whole sky was painted with them.

  12. Great, informative post to go with a terrific picture. Thank you for the education. So sorry about your friend's brother. We need to make a lot more progress in finding cures instead of just prolonging lives and managing the many varieties of this disease.

  13. That's a huge contrail, for sure.
    And loved to read the post.

  14. I hope they dident pas in the same time !!! :-) What colour would the sky be then....

    Nice weekend wishes to you, from Norway.

  15. Beautiful sky, sad story.

  16. Carole, Thanks so much. I am glad you enjoyed the post. It is a horrible shame about my friend's brother. A cure must be found.

    Quintarantino, Thanks! I'm glad you enjoyed it.

    Anemone, How awful would that have been! I am sure they were very far from each other... Glad you stopped by.

    Dick, God does awesome work. Very sad story.

  17. A very good x and lots of things I didn't know.
    Sad about your friends brother.

  18. Beautiful x-marks-the-spot photo.

    My heart goes out to your friend's brother and the family.

  19. Wow - how cool!!!!

    I know no one whose life hasn't been touched by this terrible disease. My sister-in-law has lung cancer, a secondary from a melanoma on her leg she first got 9 years ago. We thought she was clear but it came back. We are all devastated. Survival rates have gone up but melanoma cancer which is rampaging thru Australia is so nasty and so difficult to treat.

  20. Just like tom said: X-cellent! :)


  21. Very sorry for your friend.

    Great X. Keep looking up.

    This is an interesting post. I am going back through your older posts.

    You will be a daily read for me now..

    Troy In Ft. Worth

  22. Very unusual to get a "perfect x" with two contrails like that. Very nice photo indeed.

    We've had "skywatch Fridays" the last three weeks in Alabama...but its been more along the line of supercell towers & funnel clouds here. ;)

    Take care!!!

  23. John, Thanks!!!

    Dot, glad you were able to learn something. It is very sad about my friend's brother. I glad his suffering wasn't prolonged though.

    Misty Dawn, Thanks and yes, they need prayers.

    Jules, THANKS! So sorry about your SIL. What a horribly devastating disease cancer is. You're correct, no one's life is untouched. The statistics are staggering. 1 in 3. God bless.

    Ida, Thanks a bunch.

    Troy, Interesting...? I appreciate that! Glad you liked my blog enough to stick around. A daily read? Wow! Thanks. Welcome. I will try to remember to do shout outs when weather happens in your neck of the woods.

    James, It is unusual. I definitely had to capture that one. Supercells and funnels sound like PERFECT sky watch Friday occurrences to me!!! ;O)

  24. I like this one and the sunset in the next post.

  25. Thanks a bunch, Gardenpath!


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