TAF Windshear Question For Tomorrow AM

Sinistar

Sinistar

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Brad
With all the convective around here, a quick morning local flight seems like the only fair bet. Then I see in 2 surroundung TAFS around me:

Forecast period: 0400 to 1800 UTC 17 June 2018
Forecast type: FROM: standard forecast or significant change
Winds: from the S (170 degrees) at 14 MPH (12 knots; 6.2 m/s)
Visibility: 6 or more miles (10+ km)
Clouds: scattered clouds at 15000 feet AGL
Wind shear: at 2000 feet ( 610 m) AGL, from the SW (220 degrees) at 63 MPH (55 knots; 28.6 m/s)
Weather: no significant weather forecast for this period

So I've never seen a windshear like this in a TAF. Winds at surface are 120kts and 2000ft up they're 56kts and 30deg off. Like a million questions:

This doesn't give me warm fuzzys to go fly, what would it be like?

I would guess there are varying levels down to the ground?

Does this end abruptly above that level?

What would a climb from ground up through that be like? How about on landing, I would think some serious rapid down drafts?
 
Where are you located? That’s some pretty severe wind shear, and will likely cause a lot of turbulence near the shear layer. Winds and turbulence above and below will depend partly on what’s causing that kind of shear.

Those kind of winds would be a definite no go for me. Imagine descending from 3000 feet to 1000 feet headed directly into the wind. When you reach the shear layer you lose a significant component of your forward airspeed. You’ll be dropping like a rock, nose down and trying to get your speed back.
 
Donno much about wind shear, and that’s the problem... but I think someone said nothing good has ever come out a wind shear
 
Eek.

Wait and see if there’s any LLWS advisories before your flight in the morning. Any indication of such is a no go. Period.
 
What do you plan on flying around said wind shear?
 
Sorry for the 120kts (should have read 12 kts from the TAF).

The now highly unlikely flight would be in a 182. I'd probably want a experienced co-pilot or instructor with for something like this.

I am located at KGYL which is a bit southwest of the Twin Cities. Very flat around here so no mountains. It's just crazy humid. Our airport is just under 1000msl. Density altitude was 3800 the other evening! Trying to get in some flying lately but if it's not winds it's storms and if it not storms it's winds :)
 
It can be mitigated. Look at the Winds Aloft forecast and see if there is a temperature inversion which is the most common reason for nonconvective wind shear. This will also help as there is a cap on the atmosphere preventing verticle movement of air. In other words, the air might be smooth as glass, and the only way you'll know you're in the shear is your groundspeed rapidly changing. So just watch your sink rate on approach and adjust as needed. If it's really bad I might keep a bit of power in and back it off once I know I have the pavement made.

If you don't want to fly that perfectly fine. That is always your call and don't let anyone force you.
 
Obviously things can change and no pressure to fly tomorrow which is nice. When I wake up I'll check revised TAFS and then call the briefer to learn even more.

I bow to those of you who "get" weather :)
 
Sinistar said:
Obviously things can change and no pressure to fly tomorrow which is nice. When I wake up I'll check revised TAFS and then call the briefer to learn even more.

I bow to those of you who "get" weather :)
Click to expand...

Yep! You don't have the whole Clear, Blue, and Blowing 50 with 76 passengers wanting to go to Myrtle Beach. I've flown in some f'd up weather. However, the strangest thing I've ever seen is heavy snow in clear skies... The Great Lakes has some WTF weather.
 
Look at the surface analysis...... might explain what's up.
 
Sinistar said:
With all the convective around here, a quick morning local flight seems like the only fair bet. Then I see in 2 surroundung TAFS around me:

Forecast period: 0400 to 1800 UTC 17 June 2018
Forecast type: FROM: standard forecast or significant change
Winds: from the S (170 degrees) at 14 MPH (12 knots; 6.2 m/s)
Visibility: 6 or more miles (10+ km)
Clouds: scattered clouds at 15000 feet AGL
Wind shear: at 2000 feet ( 610 m) AGL, from the SW (220 degrees) at 63 MPH (55 knots; 28.6 m/s)
Weather: no significant weather forecast for this period

So I've never seen a windshear like this in a TAF. Winds at surface are 120kts and 2000ft up they're 56kts and 30deg off. Like a million questions:

This doesn't give me warm fuzzys to go fly, what would it be like?

I would guess there are varying levels down to the ground?

Does this end abruptly above that level?

What would a climb from ground up through that be like? How about on landing, I would think some serious rapid down drafts?
Click to expand...

This is not an uncommon occurance. Unless you really have a pressing reason to fly, I would stay home and enjoy some coffee on the porch.
 
Unit74 said:
Look at the surface analysis...... might explain what's up.
Click to expand...

Was going to say the same thing. Also check the prog charts and convective outlook. You've got a powerful front coming though with heavy rain and thunderstorms forecast in the afternoon.

Sounds like a good day to stay on the ground.


Sent from my iPhone using Tapatalk
 
If you fly early, you will likely find almost no turbulence. The winds "decouple" overnight with no heat to mix air at different altitudes. I've flown in conditions like this, and I generally want to make sure that the high wind isn't on my tail as I climb into it. Your wings will waggle a little, and you will see a drastic change in ground speed. If you decide to go, keep your low level maneuvering to a minimum...I'll just fly a straight in approach to simplify the wind shear thought process. As daytime heating begins, it could be very bumpy. With all of that said, it looks like you are facing very significant shear...almost 50 knots. I think I would drink a cup of coffee and listen to the closest approach control to learn something. The LLWS AIRMETS are usually issued around 30 knots, which I've found very safe to fly in as long as you approach it with thought and caution.
 
Without looking at a bunch of charts, a classic Midwest "low level jet" is probably the culprit. With that hanging around, and this soupy air mass, TAF's be damned, you might have some morning convection that would ground you anyways.
 
Yep, we see this one in in Wichita. Low level jet just above the overnight inversion. Pretty smooth transition usually
 
Report: Decided not to fly, forgot all about the wx. Woke up at 830am. No more wind shear. Called the briefer and as we spoke a LLWS warning also ended. So went up and screwed around for 45min and first try with gopro mounted. Had to do 2 go around to land..watched the wind switch and 12G17 direct crosswind when I landed, rather ugly landing. I definitely need crosswind practice, the 182 should rock that landing....well the 182 pilot should rock that landing.

Thanks to those who responded, got me to reading more about this wind shear and why it's happening.
 
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