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Jan 11, 2022, 02:34 PM
I just want to go fly!
walter3rd's Avatar
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is winter thermaling a lost cause?

during the cold days is it a bit of a lost cause to think about finding thermals? talking close to freezing temps etc. curious... thanks.
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Jan 11, 2022, 02:51 PM
Registered User
It all depends on how much solar energy makes it to the ground. Some of the best soaring days are cold. Look for clear days with noon time temps being at least 20 degrees above sunrise temps.
Jan 11, 2022, 03:43 PM
Balsa breaks better
Thermaler's Avatar
I thought the same when an OFB asked if I wanted to fly in January, thought he was nuts but went anyway. One of the many things I learned from Tiz, RIP Buddy.
Thermals form when the ground temp is warmer that the air temp so . . .

It is always nice to have a patch of ground not covered in snow.


Balsa Breaks Better
Woodys Forever
Jan 11, 2022, 04:34 PM
Registered User
No. Especially if you can fly over a heated building. Assuming you can keep your fingers from going numb. You don't actually NEED a heated building. It was 12 degrees and breezy here in the middle of the day. Too cold for me, but my guess is there were usable thermals. Make sure your battery still works when it's cold.

I used to have a servo that woukd flake out at 35°F or so. It was an electric powered model. The nimh batteries would run down in a minute or so, unless I put foam jackets on them and kept them in my pocket until just before use. Might have been interesting if they caught on fire.

Fingerless gloves are useful. Latex gloves under fingerless gloves are warmer but less sensitive.
Jan 11, 2022, 05:12 PM
Registered User
mlachow's Avatar
You loose some thermal strength from a lower sun angle and shorter days but the thermals are still there. You really want to look at the temperature difference through the day. As someone else mentioned, a 20 degree swing will usually a good sign. Since it is cold, try to get out when the thermals are going to be strongest. So that will be around mid-day. This shifts a little depending on where you are in a time zone., east side or west side.

If you want to confirm this without getting out in the cold, then just watch the birds. You will still see birds thermaling in the winter. There are also some nice thermals when the ground is snow covered. If you are flying some place that has some parking lots or large flat roof buildings around that is nice. If your MD address is correct, probably lean towards SW wind directions. The North days will probably be really cold and don't warm up anyway. But don't ignore E winds even if it is a thin overcast and the winds are light. You might be surprised by plentiful light lift.

I have also encountered some
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Jan 11, 2022, 06:32 PM
I just want to go fly!
walter3rd's Avatar
Thread OP
Thanks for the insight! Yes I’m in Maryland.
Jan 11, 2022, 07:49 PM
Registered User

You should go out and try it!

Yours, Greg
Jan 11, 2022, 10:27 PM
a.k.a. Bob Parks
bbbp's Avatar
These things work great for keeping hands and batteries warm!
Jan 12, 2022, 04:26 AM
Registered User

winter thermals

One place that works, but seems counter intuitive is over a frozen lake on a really cold day, especially if there is no snow on the ice. The ice is MUCH warmer than the air above it and can produce surprisingly strong thermals. Many years ago a Minneapolis glider guider friend of mine was doing a New Years Day Penguin Fly with a group. At one point they found themselves fairly high when the thermal finally topped out, formed a cumulus cloud and then closed in below them. Quite a few anxious moments as everyone tried to locate their planes.

As stated in earlier comments, all you need is a difference in temperature and the willingness to try it when the air temperature is really low. Below zero tends to give you the greatest difference between the air and the ice.
Jan 12, 2022, 02:43 PM
My favorite time for soaring

I’m lucky to live in NC so Winters are not as freezing as further north. Many days are just absolutely fantastic. I’ve heard it referred to as ‘stupid lift’ - noon bubble thermals everywhere - just fly somewhere and start circling and a nice, well behaved thermal will take you as far as you want to go.

LOL - stuck at work, wish I could go flying!

Jan 12, 2022, 07:15 PM
I just want to go fly!
walter3rd's Avatar
Thread OP
I try to fly all year long if possible. I fly my sailplanes in the cold but was not sure if there would be thermals hiding about. Now I know there might be. Thanks
Jan 13, 2022, 09:27 AM
Mark LSF # 3792
It's some of the best flying here in Texas and you won't run the risk of frying your brains!
Jan 13, 2022, 04:42 PM
Registered User
What I find so amazing with thermals is that they are so elusive. Two wreks ago the sky was clear blue and the wind wad modest. The temperature fluctuated from -12C to - 9C but neither me, nor my buddy could find anything worth circling in.

On the other hand, last week the weather forecast turned ot wrong. The promised blue sky was hidden behind thick clouds and a lot of fog. The cloudbsse were about 60-70m so a five second motor run was all that could be had. But even in those conditions there were thermals that could enhance the fligjt time half a minute or (occasinaly) a minute.

Am hour latet the fog cleared and the cloudbase rose to about 200m, but not even a glimpse of the sun was shown. Nevertheless I had one flight were I had no problem flying full 10 minutes from 142m launch, I even had to dive out of the clouds twice so not to lose sight of the model.
Jan 13, 2022, 08:54 PM
I just want to go fly!
walter3rd's Avatar
Thread OP
Great story, beautiful plane
Jan 13, 2022, 11:43 PM
Registered User
The bottom line, Walter3rd, is this: To find out if thermals are working on any particular day, you pretty much have to go out and try it.

The first year we competed in the New Year's Day Postal, we had several flights passing an hour - under a 100% overcast with almost no wind. This year, I got ten minutes, in the only 15-minute period I could have got ten minutes! And it was sunny and active, although within an hour after, it was also snowing! I once saw a guy launch a dlg in rain and get three minutes, mostly by passing over the camp stove we were cooking on. In Germany in 2019, I flew in a contest with the worst weather I've ever flown in, and still got a six-minute flight in air that was awesomely flat - except in spots, for maybe 20 seconds at a time: rain, overcast, a line of trees on two sides. But, line up a couple of 20-second periods where the airplane didn't sink, and that was a minute! Do it again! and a couple more times, and there was suddenly a chance to eke out six minutes.

Sometimes, it's fun to fly in what we call around here "monkey air". Meaning: this air is so good, a monkey could keep my airplane up. But it gets boring. To learn, fly in the bad air. The strong fliers fly anytime, anywhere.

Good luck!

Yours, Greg

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