Wind direction question
07-31-15 | 05:47 PM
#1
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Wind direction question
If a south wind is tailwind, a north wind will be headwind, and east wind and west wind will be side winds. What about the rest of the angles? When does a tailwind becomes a side wind? My intuition says that WSW and ESE wind would be neutral and the 120 degrees inside those 2 points will be different degrees of tailwind.
I guess there is a absolutely rational answer based in physics rather than what I experience when I ride.
I guess there is a absolutely rational answer based in physics rather than what I experience when I ride.
07-31-15 | 05:55 PM
#3
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I am very curious to know which direction this thread is going to take ...
07-31-15 | 05:56 PM
#4
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Is a wind that overtakes you called the passing wind?
07-31-15 | 05:59 PM
#5
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07-31-15 | 07:09 PM
#8
It depends on your speed, the wind speed, and wind angle. A pure 90 degree side wind looks like 45 degrees from the front if the wind is 20 mph and the bike is 20 mph.
This HED yaw calculator is fun to play with. (Scroll down to the Apparent Wind Calculator link.)
You know, of course, that riders speed up until a tailwind becomes a headwind.
This HED yaw calculator is fun to play with. (Scroll down to the Apparent Wind Calculator link.)
You know, of course, that riders speed up until a tailwind becomes a headwind.
Last edited by rm -rf; 07-31-15 at 07:16 PM.
07-31-15 | 07:58 PM
#11
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If someone is passing wind, I prefer that they remain behind me.
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07-31-15 | 08:07 PM
#12
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07-31-15 | 09:51 PM
#14
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It depends on your speed, the wind speed, and wind angle. A pure 90 degree side wind looks like 45 degrees from the front if the wind is 20 mph and the bike is 20 mph.
This HED yaw calculator is fun to play with. (Scroll down to the Apparent Wind Calculator link.)
You know, of course, that riders speed up until a tailwind becomes a headwind.
This HED yaw calculator is fun to play with. (Scroll down to the Apparent Wind Calculator link.)
You know, of course, that riders speed up until a tailwind becomes a headwind.
08-01-15 | 08:05 AM
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08-01-15 | 10:38 AM
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Look at those weather maps on TV ..
in the Northern Hemisphere, a High pressure cell circulates CW, a Low Pressure Cell Rotates CCW..
& hot air rises and is less dense , so Its replaced by cooler air , flowing to the hotter area around the topography.
in the Northern Hemisphere, a High pressure cell circulates CW, a Low Pressure Cell Rotates CCW..
& hot air rises and is less dense , so Its replaced by cooler air , flowing to the hotter area around the topography.
08-01-15 | 10:50 AM
#19
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a tailwind becomes predominantly a side wind 45 degrees away from south as you state it. Then you still get some tailwind but most of it is pushing on your side. You should get 180 degrees of some tailwind not accounting for forward resistance.
08-01-15 | 01:55 PM
#20
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08-02-15 | 05:48 PM
#22
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This is a side wind, around 40 seconds in:
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08-02-15 | 06:27 PM
#23
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Yep! That was a side wind, alright.
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