Skew-T's for Thunderstorms & Convective Activity

AggieMike88

AggieMike88

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The original "I don't know it all" of aviation.
I'm used to looking at the Skew-T diagram during winter weather for icing, cloud bases, and such.

But not sure what to be looking at or for to help predict convective activity.

Any help from the PoA crew?
 
The only thing I know is that when the CAPE number is high (over 1000), the air is pretty unstable. Today in Denver it is 920 and I see cumulonimbus. I'm sure others will have a more scientific and detailed explanation.
 
I remember something about having a dew point over 17C and less than a 5 degree spread is higher probability for T storms, plus I'd imagine a steep lapse rate might factor too.
 
Yeah, you're looking for instability (in the ambient lapse rate), a source of moisture, and something to start the lifting. I can't give a good way to get all three from a skew-t though. I usually look at storm chaser's data and sources. But it's more complex than just those three. A dry line can be the location it all starts, for example.
 
Everskyward said:
The only thing I know is that when the CAPE number is high (over 1000), the air is pretty unstable. Today in Denver it is 920 and I see cumulonimbus. I'm sure others will have a more scientific and detailed explanation.
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Yeah, it's complex. No spotter activation here today, because it's way too mixed and confused.

See differences between these two charts... Note how the two Lows are depicted coming toward Denver, but in the second one, it's all merged into a long continuous confused front and troughs behind it.

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And nothing severe was predicted here this afternoon even with plenty of heating and lifting and moisture, because the front "blew the tops off" so to speak...

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Bu the surface winds were strong and squirrelly during "frontal" passage. If you could call it that. It was a mini squall line that hadn't developed yet. It's trying to get more organized out over the plains now.

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A day like today, the individual components are there, but they don't have time to develop vertically before they're "knocked over" kinda. Back when I used to chase, long ago, we'd call today's maps and forecasts a bust... Unless we felt like driving well into Nebraska to see what managed to develop before sundown and the end of afternoon heating. Too much mixing going on.
 
Yeah, not much heating going on today here. I thought it would be warmer than it turned out to be. Good for mowing and weedeating, though.
 
Paging @scottd, Scott Dennstaedt to the White Courtesy Phone...
 
@scottd; which of your current training products would be a good review of convective?

Now that I'm IFR rated and flying more.. I am very aware that I'm not as up to speed on the appropriate weather products as I should be.
 
Sam D said:
Nate -- What app or website is this image from?
Click to expand...

MyRadar.

AggieMike88 said:
@scottd; which of your current training products would be a good review of convective?

Now that I'm IFR rated and flying more.. I am very aware that I'm not as up to speed on the appropriate weather products as I should be.
Click to expand...

IFR will make you feel like an utter weather dumbass all over again, won't it? Heh. Fly all over the place for years avoiding weather and doing just fine -- then it gets harder. :)
 
Definitely makes me respect it more.

What we've been experiencing lately is scary stuff while on the ground. I have no desire to get caught unawares and in the middle of it while flying.
 
Look for "Weather in the Vertical" on YouTube. A two parter dealing with the theory and application of the Skew-T as a helpful indicator of convective activity. It's by Ed Williams of "Aviation Formulary" fame. You'll see me associated with it, but I was just a production assist.
 
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Saw my first tornado symbol on Foreflight during an actual preflight today. Ha. Wow.
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I'm a little surprised you haven't seen them before considering where you live. I've seen them a few times... in Michigan.
 
azure said:
I'm a little surprised you haven't seen them before considering where you live. I've seen them a few times... in Michigan.
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I was being quite literal. I've never seen one during a pre-flight. I've sat on my butt on my couch and seen them, but wasn't starting a flight almost directly toward one. Ha.
 
Ah. I don't think I have, either. Usually on days when severe stuff is bubbling up I plan to stay on the ground.
 
It's starting to look like I'll be looking at that crap again tomorrow before the day is over. Try to get in a flight before it all pops. Again. Grrrr.
 
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