On Sat, 4 Jan 2014 05:58:31 -0800 (PST), "
wrote:

On Friday, January 3, 2014 7:47:37 PM UTC-5, Gordon Shumway wrote:
On Fri, 03 Jan 2014 17:40:35 -0600, philo� wrote:

On 01/03/2014 05:21 PM, Gordon Shumway wrote:

On Fri, 03 Jan 2014 16:11:35 -0500, Stormin Mormon

wrote:

Tonight in NYS supposed to be 0F, and wind
chill -10 or so. Which number is the one
which concerns water pipes freezing?
I know the pipes won't get below the actual
temp, but are they more likely to freeze,
with wind?

Wind chill is the effect the combination of cold air and wind has on
exposed flesh relative to only cold air. "Wind chill" has absolutely
no effect on inanimate objects. The wind on an inanimate object will
cool an inanimate object to the ambient temperature quicker than no
wind. It is impossible to get an inanimate object colder than ambient
temperature by using wind that is also ambient temperature.

Now, don't ever ask that question again or I'll turn this car
around...

That's absolutely correct but trader4 made a valid point.
Air in a wall would be warmed by the house and if no outside air got in
would act to keep the pipe warm. With a strong wind blowing, any warm
air trapped in the wall would be dissipated pretty fast.

What I said is completely true, period.

Actually you contradicted yourself:

" "Wind chill" has absolutely
no effect on inanimate objects. The wind on an inanimate object will
cool an inanimate object to the ambient temperature quicker than no
wind."

No, I didn't contradict myself but you just did. "Wind chill" has no
effect on an inanimate object. Wind chill is just how cold ambient
temperature feels to exposed flesh.

Now can you agree that "how cold it feels to exposed flesh" has no
effect on inanimate objects?

The wind (not wind chill) will have an effect on heat transfer.

Wind chill is a measure of the how wind causes people to feel
colder. It also has a similar effect on cooling inanimate objects
that are warmer than ambient. Therefore it can have an effect on
objects that are warmer than ambient.

Will a pail of water at 75F freeze faster if you put it
outside where it's exposed when it's 20F with a windchill of 17F or
a winchill of 5F?