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

Thursday, April 24, 2008

A weather lesson - Mesocyclones, Striation and Funnel Clouds, OH MY!

Well, it's that time again, time for posting my Sky Watch Friday shot. I am cheating a little in two ways... 1. I am posting it on Thursday (because I know I'll be pressed for time tomorrow getting ready and finished so I can head out for my conference)... 2. I posted two pics to fully capture the moment, but I guess the first one is my "Official SWF" shot. (Please visit Tom's blog to participate.) Allow to me to set this shot up if you will. I was somewhere near Kyle, SD, on June 6, 2007, filming with the Twister Sisters for the "Twister Sisters" TV show (my episode has been playing on re-runs on WEtv.) This shot is my first ever visually recognizable mesocyclone, just before one of 3 funnel clouds dropped from it (shown in the subsequent shot). This is a large mesocyclone that I experienced while I was storm chasing in South Dakota.

(abbrev. MESO)- A storm-scale region of rotation, typically around 2-6 miles in diameter and often found in the right rear flank of a supercell. The circulation of a mesocyclone covers an area much larger than the tornado that may develop within it. A mesocyclone should not be considered a visually-observable phenomenon (although visual evidence of rotation, such as curved inflow bands, may imply the presence of a mesocyclone).~NOAA Glossary
In this case, the mesocyclone was clearly evidenced by the striation on the outer edge of the specific cloud structure in the photograph...
Grooves or channels in cloud formations, arranged parallel to the flow of air and therefore depicting the airflow relative to the parent cloud. Striations often reveal the presence of rotation, as in the barber pole or "corkscrew" effect often observed with the rotating updraft of a Low Precipitation (LP) storm.
On the right side of the photograph, you can see a lowered wall cloud, and to the right of that, the rain.
Wall Cloud
A localized, persistent, often abrupt lowering from a rain-free base. Wall clouds can range from a fraction of a mile up to nearly five miles in diameter, and normally are found on the south or southwest (inflow) side of the thunderstorm. When seen from within several miles, many wall clouds exhibit rapid upward motion and cyclonic rotation.
We watched as the newly developing wall cloud on the left side of the photograph, with its powerful inflow pulled scud from that on the right, which eventually dissipated. This occurred shortly before the wall cloud on the left dropped 3 funnel clouds. Both wall clouds showed strong rotation. I've never seen anything like it (in person) before or since. The next photograph shows the descended rope funnel cloud that never touched down. There was a tornado that did develop that day in Kyle, SD (click here to see), but we missed it. Grrr...(If you click on the image you will better be able to see the skinny white rope funnel dropping from the wall cloud.)

OK, so that's my little weather lesson for today. If there is some action tonight, I will update this post in the morning; otherwise, have a fabulous weekend!

Update: Well, yesterday (Thursday) certainly did see some severe weather. Currently, there are 9 tornado reports (Wednesday's count was increased to 14 adding one in Oklahoma), but yesterday's included one in Beloit, Kansas that was reported at 1/3 to 1/2 of a mile wide!!! That is a huge tornado! There was also significant damage reported near Johnson, NE. For updates (and I'm sure pictures forthcoming) on yesterday's storms, check out these storm chasers' sites:

David Drummond
Mike Hollingshead
Dick McGowan (sure hope he was out)
Tony Laubach
Verne Carlson
Kudos to all the chasers sticking with it despite horrific prices on gas. I don't know if any of them caught anything, but they either did catch something, or saw something since they were most likely out chasing yesterday's storms. More severe weather forecasted today. I don't know if I will get a chance to post... stay tuned.

Have a great weekend!


  1. Thanks for the lesson. These are amazing. Are they peculiar to your part of the country?

  2. These are amazing. This is what fascinates me so much about storm chasing, the awesome structure. This was many, many, many miles from my area. I have never seen anything like this in my part of the country. This is a pretty typical supercell structure though, so anywhere where "severe weather" occurs indicating tornadoes, you can witness this kind of structure. Apparently, it does happen where I am; it's just much more difficult to see the whole structure because of the trees. The plains offer a much better view.

  3. I'm going to have to go on another storm chasing excursion to keep it that way. Sounds like a good plan to me!!! :O) Thanks, Carletta!

  4. I love these troubled sky shots...I love storms.

  5. Great photo! Enjoy the weekend.

  6. Wow looks a stormy time, Great capture.

    Visit my Sky watch also the Goat Man.

  7. Very, very cool!!

  8. Great Post.
    In addition to beautiful photos, very instructive

  9. Dewdrop: Great use of the sky to teach others. Thanks for the lessons.

  10. Wow, those are amazing photos! Interesting post as well.

  11. Great pictures, I love your lessons on the definitions too. Check out my SWF photo for more extreme weather if you want.


    David Webb: Nature Pictures

  12. Well, another great lesson about clouds with perfect photos to show us what we are talking about.

  13. Thanks for the weather lesson. Dramatic photos!

  14. See, blogging is educational. Thanks for the lesson.



  15. Since I came across your site I have enjoyed all my visits, as I have done again today. Your lessons are great to take.. one thing that really comes through is your excitement and thrill.. you pass that along in your post and it effects us..

    Cheers Dewdrop... now go chase a storm for next week. ;o)

  16. Excellent information with same great images, great post.

  17. Really amazing how many new weather folks you are educating on your blog Dew, great work! Monday I'm hoping. I won't be charging any of my stuff to avoid another jinx. I haven't had such a long period with no action, very frustrating.


  18. Rose, ME TOO!!! Thanks.

    Person with puppies, Thanks. I hope your weekend is great too.

    Imac (goatman?), It was definitely ripe for storms that day, but only one tornado. Thanks!

    Ellen, THANKS!

    Marcos, Glad you found my post informative. I appreciate the feedback and the compliments.

    Fishing guy, I love to teach others about weather. I am so passionate, and I think that education is the best way to help others to know and possibly protect themselves. You are welcome, and thanks for the feedback.

    Sherry, Thanks and thanks! It was a truly amazing sight!!! I will never forget it!

    David, Thanks. Glad you enjoyed the post. I will gladly check yours out. I love anything weather.

    Quintarantino, Glad you enjoyed the lesson. I will try to do this with each of my SWF shots. I love to share what I know and love.

    Meggie, You're welcome! It was a powerful experience... unparalleled.

    Lilli, You wouldn't believe how excited I got when that funnel dropped down.

    Scotty, I try. Thanks and you're very welcome.

    Tom, So glad to hear that my passion, enthusiasm and excitement about weather comes through in my posts. I want to share that with others... it's why I blog. I hope others will see the world around them in a different light after stopping by. Your comment touched my heart, Tom. Thank you. Wish I could chase...

    Daniel, Thanks a bunch. I really appreciate it!!!

  19. Mikey, Isn't it awesome how many people are getting interested in weather?! I am loving sharing it!!! Thanks for the compliment.

    I hope you get your shot on Monday. I know it was frustrating when you had that bust. I know how tough SDS can be. I'll keep my fingers crossed that you get... something.

  20. wow ... amazing! thanks for the additional info! much appreciated! :)

  21. Thanks. I am glad you appreciated it. I love sharing my weather knowledge with others...

  22. Love storms, love the images, and wow, what an amazing amount of info in your post.

  23. Really great post and pictures! Thanks for the info and weather report.

  24. Looks like you are on to something here, Dew! Now, if we can just get you back out here to the plains without busting like I did the other day, you'll really be able to provide some info and pics to support your lessons. ;) Keep it up!

  25. How very interesting! And beautiful photos too!

  26. WOW! This is so great and interesting reading. Thank you for telling us:)
    Petunia's SWF

  27. Amazing sky shots and what a wonderful cloud formation.

  28. I never could see the funnel on that without the close up view. It goes to show how difficult spotting can be.

  29. Shudder...and WOW! Amazing. I, too, appreciate what I learned here in this post. Your photos a l m o s t made the hairs on my neck stand up - very good.

    Glad you are okay!

    I'll be back here - interesting stuff!

  30. Hi Dewdrop..
    Little ol' me again.
    I called back to see how your Sky Watch had go on and to read you comments, you really need to get posted early.. I'm sure others are missing you because you posted late.. The sad thing is it is their loss.. your site IS good, it's different and informative, you have fun also. I thank you for your replie but really all the thanks should be coming from me because you grace Sky Watch by posting.. You certain Add to the day.

    No need reply to this... just except my thanks and smile.

    Tom ;o)

  31. Love the pictures

  32. Babooshka, Me too, and thanks. I was glad to offer the info.

    Dot, Thanks! You are very welcome!

    Ken, Sounds like a plan to me! I could use a plains chase!! I'm glad to share this with others, grow this enthusiasm.

    Jenty, Thanks and I'm glad you found it interesting.

    Petunia, You are so welcome! Thanks bunches.

    John, Thanks. It was something unlike any other experience.

    It was so clear in person though, Mike. Completely awesome.

    Cherie, I am so glad you were able to learn something. I was glad to share it. I'm glad you like my blog. Please do feel free to visit anytime.

    Tom, A humble thanks while I am responding to everyone else. I thought it was sky watch Friday. It seems wrong to post that on Thursday! lol

    Tommy, THANKS!

    Wow, y'all have really blown me away with your feedback. It truly is a joy maintaining this blog. Thanks for your warm response to it. I'll keep posting as long as y'all keep stopping by! :O)

  33. wow... awesome lesson! :) Thanks for this informative post... love the pictures as always... cheers!

  34. I appreciate your compliments, Ice. I am glad to spread the passion for weather.


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