Here in Madison, Wisconsin. Everyone is staying in, so I see a danger of keeping too warm, losing one's acclimatization to the cold, so that when it warms up enough for some nice winter days outdoors — back to, say, 18 above — that will feel chilly. Perhaps we'll take a walk around the block at some point in the interest of preserving winter acclimatization. There's also the interest in being able to say that you remember when it was 18 below and you don't just remember it from reading what the temperature was from inside the house: You remember how it felt.
UPDATE: Meade reports that he stood outside, without a coat, but with his hands in his pockets, for about a minute. He says it was "painful." So I step outside, without a coat, with sleeves pulled down over my hands. It's surprisingly pleasant. Predawn, 7:15. Quiet. For many years, I'd believed that what's distinctive about temperature lower than 5 below is that when you breathe you feel the moisture in the air icing up inside your nose. You need to wrap a scarf around your face to create an antechamber for the air to make it breathable. But I had no scarf, and the breathing was fine. It felt good. But the door was at my back, and I knew I could withdraw into the warmth at any second. How much that changes the perception of cold!
The weathermen can tell you how much the element of wind affects the perception of cold, but they cannot calculate the effect of the mental element, which, even if it could be measured, varies from person to person and even within one person constantly changes. Our powers of mind enable us to get out and experience nature in winter, to the point where we might actually damage our bodies. The mentally strong have their stories of frostbitten hands and feet. It is possible to get hurt and even to die. The powers of mind must also be expended to take proper precautions, the best of which is access to an indoor refuge.
By the way, speaking of factors the weatherman doesn't report when they tell you what the wind makes the temperature feel like, how about the effect of wearing a woolly hat, a scarf around your face, insulated mittens and boots, and a very warm, long coat? They tell you the wind chill factor, but never the coat-warmth factor. The wind-chill factor is based on the feeling of blowing cold air over naked skin. To really know how it feels, I need to redo my front-stoop test naked. But dawn has now struck, and my test results would be crazily skewed by the public-nakedness-embarrassment factor.
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You get used to any temperature.
After a couple of weeks below 0F, anything above 0F feels balmy.
Wind chill is a bogus number to gather viewers.
The wind is completely variable depending on where you are and what you're doing. No number makes sense.
Except temperature.
You've got it dead wrong, Professor: I'll predict that as soon as it hits the 20s, the college kids will be running around in t-shirts , shorts and flip flops. Gotta remember that everything is relative...
We didn't get plows in our neighborhood until almost midnight last night. Very unusual to see our streets as smooth and deep as the yards around them.
Something is what two bodies in contact come to the same of.
Imagine that the bodies know to stop changing when total something is maximized, call it S for something.
That means that the bodies exchange energy until the guy (call it) has energy U1 and something S1, and the gal has energy U2 and something S2.
That means that S = S1 + S2 doesn't change when energy exchange happens. Otherwise S wouldn't be maximum.
So the change of S1 with respect to U1 has to equal the change of S2 with respect to U2. Otherwise you could change the sum by swapping energy, and in particular raise it.
The change of S with respect to U is temperature. Bodies stop exchanging energy when their temperature is equal.
S is called entropy.
All this is interesting because a really simple nonmathematical argument comes upon the precise definition of temperature.
Which has nothing to do with molecular motion, the science class definition.
Wind chill doesn't enter in.
I think I'll spend enough time outside to clear my driveway.
Wind chill is noticeable, with a certain amount of wind. Unless you've managed to get a good windbreaker-layer above your insulating-layer.
@rhhardin,
wind chill is an attempt to measure the rate of heat-loss-by-convection, as modified by wind.
It should be stated as "the average person will feel a loss of heat energy with wind speed X as if they were in still air at temperature Y".
As you say, it is one way to make cold-plus-wind seem scarier.
Rhhardin. I am with you on the wind chill nonsense. How about the "wind chill" if I rode naked and wet on a motorcycle at 80 mph?
Yeah, the wind chill number is, "what it would feel like if you ran around naked." When I lived in Madison, I found that once I hit a temp that required maximal skin coverage and insulation it was all pretty much the same. I think the coldest we hit was -22, so I guess this theory could be put to a stronger test. I have a friend who is going up around the Arctic circle to see the northern lights. He's a good guitar player, I hope he comes back with all the important fingers.
Rhhardin. I am with you on the wind chill nonsense. How about the "wind chill" if I rode naked and wet on a motorcycle at 80 mph?
If you're a bike rider, it's always wind. In fact to first order the wind is always the same, since relative wind is what limits the speed of the bicycle.
Beards cut down the skin-level wind, which is why bike riders don't shave in really cold weather.
If you want really really cold hands, spill gasoline on them while refueling your airplane.
Wind chill doesn't enter in.
It's relative, of course, and I understand how the weather biz folks have to hype it, what with all those Doppler color radars and stuff on TV and all.
What always gets me is the guy who puts cardboard behind the grill in his car - in front of the radiator - at sunset, as if that's going to help.
Pesky global warming/climate change!
It's -5 With a wind chill of -25 in the northwest corner of Arkansas. I'm definitely going outside.
Doesn't the wind chill number offer some guidance on how warmly to dress?
The wind certainly affects the feeling (and the dangerousness) of the cold, it's just the translating that into an alternate, scarier-sounding temperature is sensationalistic. It's a number that should help you understand, because we are familiar with the temperature numbers, but what's being understood is an exaggeration.
You're in Madison. You, outside au naturelle in sub zero weather wouldn't even register.
Wind chill? Hah. Back in the day, we walked to school in this weather - uphill both ways. Kicked the snow off the power lines while we were at it. We were tough back then. *cough*
I went outside this morning with just a light coat on. It's 55 here in NJ. Gonna be 13 tomorrow.
Weather. I blame Algore.
PS There is no comparison between 13 above and 18 below. Those are two different universes.
You can estimate the temperature from the sound the snow makes when you walk on it.
I do not miss cold Michigan winters at all -
Incidentally, 18 below is NEWS and worth talking about.
The way they talk about a 6" snowstorm here in the NY area is bizarre. You'd think this doesn't happen EVERY YEAR. I think a lot of people have actually tuned out the news version of weather as it relates to snow.
Two inches of snow on the way !!!
Close the schools, open the shelters, buy a months worth of food, check your batteries, buy a generator, blah, blah, blah.
There is a cryotherapy place here. You go into a small, fancy, very cold box for a couple minutes. Wikipedia on cryotherapy:
"The chamber is cooled, typically with liquid nitrogen, usually to a temperature of −120 °C (−184 °F)—although temperatures of −140 °C (−220 °F) or even −160 °C (−256 °F) have been used."
Hm. No thanks.
It was -18 here a couple days ago, but now the temp is an oppressive 40. No seriously, once it got to about 18 degrees, it felt warm again.
As for wind chill, while I sympathize with disdain for it, the difference between ice fishing when it is ten and windstill an ten and windy is night and day.
The measures, of course, were for the military to calculate minutes to death likely occuring. "Wind chill" was a part of the process. As far as being a part of a peacetime civilian weather forecast, I don't know. Maybe we should just give an estimate of the safe amount of time you can be out in the wind and cold--like we do with sun exposure now.
Funny how they never mention the breezes in summer that make hot temps feel cooler.
Instead they switch to artificially jacking the temp up via "humidity."
The wind certainly affects the feeling (and the dangerousness) of the cold, it's just the translating that into an alternate, scarier-sounding temperature is sensationalistic
This is it. An early morning with extreme cold and no hint of breeze is 'surprisingly pleasant' as Ann notes, yet a warmer morning with a comparable wind chill temperature might be unbearable. Wind chill seems a poor metric, and we're on the lookout for better measures. We've experimented with the 'golf-o-meter' a 0-10 numeric scale quantifying temperature, wind, sun and precipitation, by type and severity. We've also set a pleasantness index dividing line according to whether or not the dog shoots you a 'you've got to be kidding me' look when you open the door.
One of the reasons, of many, that Florida increases their congressional delegation every ten years.
My mom has -28 air temp in Rhinelander this morning. That's cold.
and my test results would be crazily skewed by the public-nakedness-embarrassment factor.
And, believe me, the "crazily" part of the public-nakedness-embarrassment is very subjectively skewed. Heck, it's making my nipples erect just typing this.
rhhardin said "Wind chill is a bogus number to gather viewers."
Indeed. There should be a countervailing thing for, say, Florida: "heat mop", calculated as what 95F feels like when humidity is 80%.
I grew up in Arizona, and it sometimes got up over 115F. They say "it's a dry heat!" Yeah, well, get out into 115F and enjoy the dryness. Or, as the Professor suggests, strip naked and get out into cold temps and try calculating the cold.
Our neighborhood is lousy with joggers most mornings...including this morning when it's -7 outside.
Isn't there something about jogging below a certain temp because of what the cold does to your lungs?
On these really cold days I get a feeling of cold, warm, cold when I go for a run: It takes a mile or two to warm up, then I am nice and warm for a few miles, finally fatigue sets in and my pace declines--the built-up moisture and decrease in tempo leads to a bone chilling final couple of miles.
I walked in to work. It wasn't horrible. Quiet.
I was kinda bundled, of course.
All of you science-denying Republican conservatard wind chill haters are missing the simple fact that you DO lose more energy with the wind blowing. You can consider the wind chill to be a scare factor, but if meteorologists (or "weathermen," as the patriarchy shill Althouse refers to them) start using things like heat transfer coefficients then the public won't be suitably alarmed and the gravy train for Big Garment comes to a halt. Follow the money.
Did a nice little stroll at 7:00 a.m. when we bottomed out here at -23. It has been a few years since we hit -20, so I thought I'd experience it. It was 1996 when it got to -30 where I was living. I'm not sure I can tell the difference between -20 and - 30 though.
Walking into the wind was the hard part. Otherwise, I wasn't out long enough to get really cold.
'There should be a countervailing thing for, say, Florida: "heat mop", calculated as what 95F feels like when humidity is 80%.'
There is. It's called heat index, and it's used frequently in locations which experience both high temperature and humidity. Sadly, is hasn't caught on as easily as wind chill. Big Garment strikes again. Follow the mnoney.
In the movie "Saving Mr. Banks," Walt Disney recalls when he and his brother delivered papers in the winter in Missouri...through snow drifts...before and after school...his father, who had the routes totaling 1,000 customers, whipping him with the buckle-end of his belt.
Result?
Young Walt was too wet and tired to study. All he had the energy to do was doodle.
Fairly rough scene for a movie made by Disney featuring the man himself.
Today it's child abuse. Yesterday it built character.
Actual -45F temperatures are a different world. Plastic items get brittle and break when dropped, cars need to be plugged in to heat the engine block when parked, and adequate clothing and boots are essential. A few unprotected seconds won't kill you, but a few minutes can start you on the way.
There should be a countervailing thing for, say, Florida: "heat mop", calculated as what 95F feels like when humidity is 80%
Such atmospheric conditions don't occur. To have a relative humidity of 80% with a 95F temperature requires a dewpoint of 88. Not going to happen, ever, in Florida.
I believe that wind machines are used in the flash-freezing process in food production. Right?
You're a lot slower working out in the cold, but it doesn't take extreme cold.
You heat all the air you breathe in to body temperature. That takes a lot of energy, which takes up a lot of your aerobic capacity.
You go slower to compensate, whether you want to or not.
A heat exchanger solves the problem, except nobody makes one that doesn't use the same path for incoming and outgoing air, which means you breathe first the CO2 that you just exhaled.
A proper heat exchanges has two paths thermally adjacent, so the outgoing hot air heats the incoming cold air, but the incoming air is fresh not exhaled.
Whether the sun is out seems to me to make the biggest difference.
MadisonMan, but percentage humidity is relative to heat. They used to speak of humidity as a linear thing, unrelated to temperature, but I don't think they do that anymore. 90% and 90F seem quite possible to me, but I don't know Florida well.
Crimso, I've heard of the "heat index". Small Garment is trying to move it, but most people just look bad in thongs.
Wind doesn't matter much if you're covered with wind proof clothing.
Humidity makes high or low temperatures much worse.
Sometimes you do need a weatherman to know how cold it is.
If you want really really cold hands, spill gasoline on them while refueling your airplane.
If you want really warm hands, light them.
Margarent Thatcher Naked on a Cold Day!
Margarent Thatcher Naked on a Cold Day!
90% and 90F seem quite possible to me, but I don't know Florida well.
It's not possible.
You can have high relative humidity in the morning, but then it drops as the temperature increases.
A good rule of thumb: If the temperature/dewpoint spread is 20 F, then the relative humidity is somewhere around 50%.
95 with a 75 dewpoint, while only 52% relative humidity, feels horrible. But you get used to it.
There's another opportunity to do the naked test tomorrow morning.
I find all this hysteria about the cold quite interesting. I grew up in Madison and back in the fifties it was quite normal to have two or three stretches of 20 to 25 below every winter. It was straight temp, wind chill didn't exist at the time. I don't recall coming off the rink or the ski hill for any of it. Seems today any weather which is in the least anomalous is "biblically catastrophic". Speaks a lot more about us than it does about the weather IMHO?
. When evaluating cold weather, I find it is not the severity butthe duration that is the key factor. The very first days of cold weather are bearable and sometimes even exhilirating. But they get old fast. Generally by February, travel to warmer climes does not seem like sch a waste of time and money, and wearing a short sleeved shirt seems like the most profound sensual pleasure available on this earth.......The thing that saps your resolve is nt the cold or the wind chill, but the slush. I can stand many things about winter, but a shoe full of slush is beyond all human endurance........Inertia is one of the guiding principles of my life. It takes a lot to get me out of bed, much less take a trip to Florida, but too much winter will do it.
And another amen to Alan's comment.
I' m so tired of all the talk about the weather, especially in our narcissistic society. It's all about the cold, the heat, the rain, the snow, the dire lack of rain, the torrential rain, the blizzards burying us, the killing frosts, the stifling humidity, and on and on. We talk as if we were the first humans to ever experience weather and its extremes. We're always having the worst of the worst. The storm of the century! Ice age cold! Hellish heat!
Oh my lord! I just looked outside! It's snowing in Tennessee! Snowing I tell you! Nature, thy name is death!
Oh. It stopped.
It's sunny and cold.
Kind of loses its effect when you put it that way doesn't it?
Thank God for Global Warming, without which Wis. would be 45 below, wind chill -145.
Here I am in Miami where it's 78 degrees now. To think tonight I will lower my a/c to a temperature you guys warm your homes to.
Any men in shorts out?
BTW, as a sojourner in milder climes, I always thought cold was cold, and that once past a certain point it doesn't matter.
Guess i was wrong.
Reminds me of that great Jack London story - To build a fire.
But all this—the mysterious, far-reaching hair-line trail, the absence of sun from the sky, the tremendous cold, and the strangeness and weirdness of it all—made no impression on the man. It was not because he was long used to it. He was a newcomer in the land, a chechaquo, and this was his first winter. The trouble with him was that he was without imagination. He was quick and alert in the things of life, but only in the things, and not in the significances. Fifty degrees below zero meant eighty-odd degrees of frost. Such fact impressed him as being cold and uncomfortable, and that was all. It did not lead him to meditate upon his frailty as a creature of temperature, and upon man's frailty in general, able only to live within certain narrow limits of heat and cold; and from there on it did not lead him to the conjectural field of immortality and man's place in the universe.
Thanksgiving morning in Hanover NH 1994-26 below zero. I returned to California the next summer. and stayed.
"Rhhardin. I am with you on the wind chill nonsense. How about the "wind chill" if I rode naked and wet on a motorcycle at 80 mph?"
A hilarious Tom Bodet routine is about four people who have to ski naked back to the road after their clothes burn up in a warming hut next to a hot tub. It's 5 below zero in Homer Alaska. One of his funniest routines.
Shorts are for all year.
You add sweat pants over them, to get the right cooling profile on a bicycle.
One pair of sweat pants for 30-42 degrees.
Two pairs for 20-30 degrees.
Three pairs below 20.
A face mask under 15.
I grew up in Madison and back in the fifties it was quite normal to have two or three stretches of 20 to 25 below every winter.
You are demonstrating how human memory tricks you.
There were 8 days with lows below -20 in the 50s, one in 1950, 5 in 1951 and 2 in 1959.
It's seven degrees here in Nashville, which is the coldest I've ever been. Somehow it doesn't feel terrible, which I think is because the sun is out.
The Meals on Wheels program is closed in our area of Wisconsin today and possibly for tomorrow. I hope these people have another way to get nutritious food.
"But the door was at my back, and I knew I could withdraw into the warmth at any second. How much that changes the perception of cold!"
Exactly. Waiting for a bus that you pray is on time or finding one that drops you off closer than a 1/2 mile from home, puts you in a different mindset.
The news people have to drive eyeballs to the tv or newspapers somehow I guess.
Here in California (should be a high of 60 in the Bay Area today)all the talk is of lack of rain this year. That, and endless Spare the Air days which means the Fireplace police can ticket you for burning wood. But the minute a rainstorm hits, the news shows all do the "STORM TRACKER" logos and have idiots standing in the rain reporting on, well, the rain and a few car accidents due to the rain. And maybe a tree fell due to the rain.
I find cold very painful, not just uncomfortable. I continue living where it can get cold only because of my kids.
Dry heat: Many years ago, I moved from Arkansas to Arizona on labor day weekend. One night I was packing a trailer in Arkansas, two nights later I was unpacking it in Gilbert (outside of Phoenix.) It was almost 20 degrees hotter in Arizona, but pure bliss compared to Arkansas.
I lived in Alaska back in the 80's, and have been commuting to Alaska from California for 12 years now to work in telecommunications. Sometimes my work takes me up a communications tower in the Arctic winter.
I will take a day at 40 below over a 20 below day with winds, and anyone who has worked in those conditions will say the same. The wind is brutal in those temps.
I was working in Barrow about 8 years ago on a winter day when the temperature shot up to about 15 below. All of the local children seemed to be outside playing. My buddy and I imagined the conversation in the homes:
"It's a beautiful day outside, you kids go out and get some fresh air".
Anywhere else it's called child abuse.
This global warming is a bitch, isn't it. We are even getting it down here in PR.
It is about 78 degrees outside but with the windchill, it feels like 77.
So chilly I had to change my shorts for a pair of jeans. That will gladden Ann's heart.
And a happy Three Kings Day to everyone as well. If you don't know what Three Kings Day is, they probably didn't visit your house last night to leave presents. Them Kings don't play.
John Henry
Turn the thermostat down to 65, and lower at night, if possible. Works for me, YMMV ...
@John Henry: it's also my daughter's birthday (and Norman Reedus's birthday). The day after she was born 26 years ago there was a big snow storm down here in the South. Today it's much colder (in the single digits tonight) but no precipitation.
We keep the thermostat at 62 during the day and 50 at night.
Meade reports that he stood outside, without a coat, but with his hands in his pockets, for about a minute. He says it was "painful." So I step outside, without a coat, with sleeves pulled down over my hands. It's surprisingly pleasant.
The first thing that popped into my mind when I read those four sentences: A tongue-in-cheek Althouse-Meade version of "Anything You Can Do" (I Can Do Better). :)
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