WX RADAR and Tornado vortices? How to avoid?

wheelsup

wheelsup

Well-Known Member
OK with this crazy weather descending down upon us I'm been looking into tornados and their vortices.

What I'm specifically worried about is grazing a vorticy while deviating in embedded CB's. I've read that vortices can be in clouds with tops as low as 12,000 ft. and situated both vertically and horizontally, and in some cases can be in clear air, which particularly bothers me if true. I've also read to avoid the 7-8 o' clock position of the storm relative to it's motion, as that is where tornados generally form.

Any ideas from the experts? I'm not so much worried about hitting a thunderstorm, but that I'll run into a horizontal vorticy. I do know about the "hook echo" however it seems extremely hard to make out when the weather guys are pointing it out to you on TV let alone while you are up there getting the crap kicked out of you.

I guess where this is stemming from is apparently these horizontal vortices are pretty common occurrences and the recommended berth is 20 miles from a level 5+ storm. That being the case, it would seem only prudent to hold if the storm is closer than 20 miles to the airport, which needless to say can cause some hardships with the operation of an airline.
 
I don't think the radar in the CRJ is going to be much good in painting anything that will show tornado vortices. I think the best bet would be looking for hooks coming off the main cell and avoid both the inside and the top-outside areas of the hook.

The CRJ has the -840 radar on it. The -850 is capable of turbulence depiction (in the form of shear zones) using some sort of Doppler computations. I would bet this would show vortices rather clearly.
 
Honestly there is no way you are going to know where a tornado is going to be. You do know however where they aren't going to be. Personally I avoid any cells that are greater than 45K tops because above that the chances for hail/tornadoes are good (hail+airplane=bad day). Gust fronts however are really nasty sometimes. This could possibly (though I wouldn't know) could feel like your in a tornado sometimes.

Before I ever leave the ground I take a look at the metars as a cell/front has moved through.
Key things to look for. Look to see if there is a wind shift and how much the direction and speed has changed. See how low the ceilings were. Usually the lower the ceilings the worse the ride will be (my experiences). Most importantly, look at the base reflectivity of the storm, not just the composite if you're a low flyer. The composite view usually always looks like doom and gloom compared to the bases. I can usually determine if there are good chances of tornadoes/hail in the area by looking at all of these key things before leaving the ground.

If you are going to punch through a storm you are correct about avoiding the southwest side of the storm, however if you are passing a line even though your avoiding the south side of one cell you may be on the bad end of another.

One thing to remember is that weather is extremely dynamic and can change in a relatively short period of time. My experiences have helped me determine whether I know if it will get better, worse, or staying the same in a 2-3 hr flight.

I know this is extremely vague, but like I said it weather is dynamic and it almost takes a 6th sense gained by knowledge and experimentation if you want to bust through storms. Some people don't like or condone doing it, but I don't bash other PIC's for their decisions to sit on the ground. Sometimes I join them.
 
Here this is what I am talking about:

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I've outlined in red what a horizontal vortex would look like on radar and where it would be. It's not over the "primary" return, it sticks out as a finger as a "flanking line" on the upwind side of the storm. As you can see, they don't paint well on your radar.

Here's another view showing almost NO return:

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Apparently they can form up to 20 miles away from the primary level 5/6 storm, which is why I wonder about going into an airport with an approaching large storm. I can easily see punching into that thing at night or if it's embedded (tops were about 15,000'). That's why I'm wondering, is it just better to give a 20 mile berth to these storms? Airborne that is easy, but t/o and landing is a different story.

Looking at that second radar return, before reading about this, I personally wouldn't think twice about taking off or landing into it provided I didn't see it out the window. It's a measly 1/2 return (at best). Big F'ing deal I would think.

A 20 mile avoidance is the easy answer but would almost make flying in the the midwest and east coast during the summer impossible on bad weather days with an approaching storm. The good news is it seems they are limited to the 5/6 cells, we don't get many of those on the east coast. Here's the kicker - it's been calculated that an aircraft has a 1:6 chance of hitting a horizontal vortex if they hit that part of the storm.
 
In that instance I wouldn't go around the south side of the storm. It seems easy enough to miss it on the north side by 5 miles no problem. That's best way to stay out of any vortex by a single cell like you and I keep reiterating.
 
Just a silly, stupid, little 'ol question, despite what "everyone else" is doing, what is your company's policy on flying in and around thunderstorms?

Have you asked the person that wrote the policy?
 
SlantG said:
Just a silly, stupid, little 'ol question, despite what "everyone else" is doing, what is your company's policy on flying in and around thunderstorms?

Have you asked the person that wrote the policy?
Click to expand...
If we were to stick to company policy on everything, I doubt we'd ever get off the ground. Anyway it's 10 miles below 10k. Which could still put you into one of those things. Our weather radar training, even as a new hire, consisted of a handout and an AT video. That's about it.

This was more meant to start a discussion on the topic, however I suppose we aren't weather experts here :D. I never even knew these "flanking lines" even existed. I suppose the safest answer, and most conservative, is to avoid them by 20 miles and go hold until that allows you to get into the airport. You just don't see very many operators, if any, doing that. It's more like everyone gets in until the cell is on top of the field.
 
wheelsup said:
If we were to stick to company policy on everything, I doubt we'd ever get off the ground. Anyway it's 10 miles below 10k. Which could still put you into one of those things. Our weather radar training, even as a new hire, consisted of a handout and an AT video. That's about it.

This was more meant to start a discussion on the topic, however I suppose we aren't weather experts here :D. I never even knew these "flanking lines" even existed. I suppose the safest answer, and most conservative, is to avoid them by 20 miles and go hold until that allows you to get into the airport. You just don't see very many operators, if any, doing that. It's more like everyone gets in until the cell is on top of the field.
Click to expand...

I'm really surprised you don't get more training in radar.

Didn't we have a REALLY good discussion here about a year ago? There was another pilot - famous, as I recall - who was here on the forum discussing the nuances of airborne radar and how to use/interpret the data it returned?
 
killbilly said:
Didn't we have a REALLY good discussion here about a year ago? There was another pilot - famous, as I recall - who was here on the forum discussing the nuances of airborne radar and how to use/interpret the data it returned?
Click to expand...

Yeah I was hoping he would stop by.
 
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