Every time I think I understand a little about weather

455 Bravo Uniform

455 Bravo Uniform

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455 Bravo Uniform
...I get kicked down a couple notches.

OK, from this chart, I would have guessed all is going to be great weather, flanked by high pressure, and high rolling in, no cold front to speak of, flat pressure gradient (Indiana):
3E74C582-39E9-455B-A24D-FCD03FDB82E2.png

Then the radar looks like this:
091856D5-B3B6-4A9A-BC87-9E3978170F02.png

So then I try to learn by reading the discussion. Starting with “...solid cirrus shelf...” through the end, and I’m like WTF?!
BD39CBEE-442F-4A4E-8C20-57C4E29D7EFD.png

I’ll just look up for clear skies and keep my flights local, f it, I’ll never learn without a college course.
 
Heck, the meteorologists around here can't figure it out either. And they gots sheepskins and sell it for a livin on the teevee.

They looks at all them charts and stuff you look at, and then the go to the computer to see what that artifishul telligence says and then out pops a model.. and iffn they don't like that one they gets more... And then they get the yourpeein model and it says sumthin else...

I got me a weather rock. It's accurate alla time.
 
The Great lakes region is very difficult to forecast. Lots of lot son variables make for chaotic outcomes, which are unpredictable by nature.
 
I don't speak weather, but I think the J/KG CAPE is the issue, potential energy in the atmosphere.
For a real brain buster, go look at the other dimension of the atmosphere in the Skew/T charts, that's where a lot of the magic lies.

Here's a good site for the pretty graphs, with a few links to WTF they are: https://rucsoundings.noaa.gov/
 
Highs spin clockwise, so the left H is pulling down colder air from the north, the right hand H's (all three aligned) are pulling up very hot humid air. Where are the airs mixing? Over Indiana and Ohio.
 
steingar said:
The Great lakes region is very difficult to forecast. Lots of lot son variables make for chaotic outcomes, which are unpredictable by nature.
Click to expand...

You think that’s bad, throw in a few daughters and the chaos goes up by a magnitude of 8.
 
I feel your pain. On the way out from CA to Oshkosh, we made our fuel stop in Tucumcari, NM, and were poring over the prog charts trying to get a sense of where a decent-size storm system was moving. Should we try to do an end run up to Minnesota? Or take a more direct route and stop short of the storm, and wait it out? We ended up doing the latter and overnighted in Topeka, KS. The next morning, the storm still looked pretty brutal, but contrary to the prog charts it started to thin considerably in our direction of travel over the course of several hours. We took off and made a nice smooth flight between the cloud layers with zero turbulence.

So when in doubt, wait it out. The delay meant we had a real nice breakfast at a Cracker Barrel in Topeka. Twist my arm!

IMG_4029 2.jpg
 
Humid AF + summertime = ripe for convection.
CAPE of 3810 in FWA with the temp and dewpoint merging in the 4000' range.

CAPE of 4180 in GRR :eek:
 
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I look at that first chart and see the squall line in Illinois and only see bad things for Indiana. No expert here, but that chart would give me serious pause unless I was flying the heck out of there.
 
455 Bravo Uniform said:
...I get kicked down a couple notches.

OK, from this chart, I would have guessed all is going to be great weather, flanked by high pressure, and high rolling in, no cold front to speak of, flat pressure gradient (Indiana):
View attachment 77070

Then the radar looks like this:
View attachment 77071

So then I try to learn by reading the discussion. Starting with “...solid cirrus shelf...” through the end, and I’m like WTF?!
View attachment 77072

I’ll just look up for clear skies and keep my flights local, f it, I’ll never learn without a college course.
Click to expand...

So you look at the SA chart and expect to understand it?
 
What are you guys seeing in that first chart that I’m obviously missing? Trying to learn (on POA, yeah, don’t laugh, please).
 
455 Bravo Uniform said:
What are you guys seeing in that first chart that I’m obviously missing? Trying to learn (on POA, yeah, don’t laugh, please).
Click to expand...

The squall line ( two lines with two dots )and the fronts are a warning sign for me. The outflow boundary depiction also would concern me that there is some big activity around there. Then you see that radar image and that's the final nail for me depending on what I want to do. I would also look at the prog charts. Finally I would read the forecast discussion, where it pretty much spells out you will have a problem. Some the discussions get technical, but usually there is a pretty good summary in them. I'm still learning. Sometimes fronts are no big deal, sometimes they are a very big deal. In the end though, you need to look at more than one chart.
 
PaulS said:
The squall line ( two lines with two dots )and the fronts are a warning sign for me. The outflow boundary depiction also would concern me that there is some big activity around there. Then you see that radar image and that's the final nail for me depending on what I want to do. I would also look at the prog charts. Finally I would read the forecast discussion, where it pretty much spells out you will have a problem. Some the discussions get technical, but usually there is a pretty good summary in them. I'm still learning. Sometimes fronts are no big deal, sometimes they are a very big deal. In the end though, you need to look at more than one chart.
Click to expand...
I’m think he posted the radar to show reality after his prediction it would be nice based on the forecast in image one. If he’d had the radar he wouldn’t have made the same prediction.
 
Salty said:
I’m think he posted the radar to show reality after his prediction it would be nice based on the forecast in image one. If he’d had the radar he wouldn’t have made the same prediction.
Click to expand...
I think they are both from the same time. The surface analysis is usually pretty close to real time.
 
Salty said:
I’m think he posted the radar to show reality after his prediction it would be nice based on the forecast in image one. If he’d had the radar he wouldn’t have made the same prediction.
Click to expand...

That is pretty much the idea. I wasn’t planning on flying today due to work. For practice, I try to look at radar and then imagine what the prog chart would look like. This one blew my mind when I looked at the chart.

The not-so-subtle clue that I totally missed was the squall line depiction. The outflow boundary text I saw, but didn’t understand it’s significance. Two major errors caused by lack of understanding. I’m going to research more. Thanks @PaulS

Now as far as the discussion section, I’ve used that since I was a student to learn. It’s a great tool. I’ve learned a lot, but get thrown for a loop sometimes, and this was what happened. Misread the chart, didn’t understand what was actually happening outside (radar), and the discussion left me more clueless than before.

I’ll post some future forecaster discussion here to try to get some deciphering help.
 
455 Bravo Uniform said:
That is pretty much the idea. I wasn’t planning on flying today due to work. For practice, I try to look at radar and then imagine what the prog chart would look like. This one blew my mind when I looked at the chart.

The not-so-subtle clue that I totally missed was the squall line depiction. The outflow boundary text I saw, but didn’t understand it’s significance. Two major errors caused by lack of understanding. I’m going to research more. Thanks @PaulS

Now as far as the discussion section, I’ve used that since I was a student to learn. It’s a great tool. I’ve learned a lot, but get thrown for a loop sometimes, and this was what happened. Misread the chart, didn’t understand what was actually happening outside (radar), and the discussion left me more clueless than before.

I’ll post some future forecaster discussion here to try to get some deciphering help.
Click to expand...

Doug Morris and Scott Dennstaedt have a great book out that I read and it really helps deciphering this stuff. The main thing they stress is not to focus on one thing, but to try to see the big picture. They do a good job going over the different charts and how to use them. Another useful tidbit is to emphasize present conditions (metars, pireps, satellite pics, radar ) over forecasts when the flight is close. Forecasts can be wrong, especially for the degree of accuracy we demand to decide a flight. Finally get an IFR rating, it really helps when the clouds start closing down.
 
455 Bravo Uniform said:
What are you guys seeing in that first chart that I’m obviously missing? Trying to learn (on POA, yeah, don’t laugh, please).
Click to expand...

Here’s what’s up. Convection doesn’t need any frontal activity. It helps. But all it needs is mixing and lifting. The frontal chart can be completely blank for hundreds of miles but thunderstorms can be popping there soon.

It might need shear aloft to help it get started (like mentioned in the text) or heating (also what they’re referring to in the text — the shelf of non-convective clouds out in front of the high can act like a sun shade and slow daily warming enough that convective capable air won’t rise enough to make it pop off). Stuff like that.

But that chart won’t really show the possibility of convective weather. Not directly anyway. The front coming into unstable air ahead of it is the only hint it gives. We know what fronts usually do when they run into unstable air. (But you really need the CAPE number or a Skew-T picture to know it’s unstable there in the bit open nothing on the frontal chart.)

You need convection prog charts with that one. The Categorical Outlook on that day may have shown it. Along with the forecasted SIGMET/AIRMET chart. Both tend to be fairly widespread through in their areas that will likely be affected. Good warning to keep up on changes though.

That big surfer curl in the radar map is cool though. Look at that storm create its own low and turn... nifty.

But it’s not a FRONTAL low. It’s the low in the core of a thunderstorm. A thunderstorm that developed because heating and shear set it off. Mr Air Parcel’s Wild Ride.

Make sense? :)
 
Yeah, us folks down here in Florida are used to thunderstorms popping with no front since it happens almost every day in the summer. Good call out on this scenario though.
 
Bobanna said:
Wouldn't a CAPE/ lifted-index chart be more predictive?
Click to expand...

Maybe. The glider folks watch them like hawks... pun intended. But you don’t always get something to start the lifting and set it off. Or more commonly, you don’t know what time it’ll pop off. Especially with summer heating. Cook...Cook... Cook.... Cook... boom.

CAPE shows it’s capable of being lifted. Then something has to mix/lift it to make it go.
 
Freely admit I don't delve into weather. . .not being a meterologist, or inclined to study it, I go with the forecast - done by people better prepared than I.

I did learn not to take off on the leading edge of a cold front. Other than that, AWC. . .
 
Sundancer said:
Freely admit I don't delve into weather. . .not being a meterologist, or inclined to study it, I go with the forecast - done by people better prepared than I.

I did learn not to take off on the leading edge of a cold front. Other than that, AWC. . .
Click to expand...

A whole bunch of long XCs more than a couple States away really forces the issue. I did a lot of that VFR over many years and also had some college level meteorology courses. Which mostly taught me that it’s very very very detailed guesswork sometimes haha.

Back when we barely had radar at WSI terminals in FBOs and the like, and paper charts, if I had to cross a messy boundary on a convective day, I’d fly until it looked bad out the window and then land just to look at the updated charts and radar. I had some diversions that took me hundreds of miles out of my way, but kept me out of the nasty crap, and only made me a couple hours late. And more Avgas. But avgas is a lot cheaper than a funeral I figured.

Plus I got to see all sorts of new and interesting airports. I’d say “places” but we often didn’t go anywhere. Just gas up, check WX again and go.

I remember an APA to DWH trip in a Skyhawk where I ended up somewhere in West TX after College Station area to go around a massive long line of crap. We landed at DWH as the tower closed for the night.

Nowadays those trips would be sooooo much easier. Especially with the IR, but even without it. But the old way to us was fun. Just a long damn day. Ha.
 
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