Do you dress for the current temp. or the "Feels Like" temp?
 

We always get the "FEELS LIKE" temperature in the winter, once the windchill is added. Since we are on bikes, often times that is even worse if we are going against the wind.

Just wondering if its better to dress for the temp (currently -10 in Toronto) or for the Feels Like Temp of (-19)?

Or does it make a difference at all?

I ask because I want to re-start my commute tomorrow and im trying to decide on clothing. Temp will be -9 in the am, with a feels like temp
of -17.

Is the "Feels Like" temperature based on wind chill? I ignore wind chill due to the windproof gear + you're always going against the wind when biking anyways.

As long as you're wearing wind-proof gear (i really hope you are if you're year round cycling) then the wind-chill/"feels like" isn't a good estimate for you... i don't use it because every mm of square skin is covered in something which cuts most of the wind out... the actual temperature is what i usually go by unless the wind is going to be horrible. If the wind is very strong then i might subtract a few degrees from the acutal temp but those feels like measurements are for exposed skin.

I ignore wind chill. I'm going to be adding 10-15mph of wind to it which makes a joke of wind chills based on a breeze.

Then you include the fact that you cover virtually all of your skin (and in the case where wind chill is very bad I'm covering everything) and the wind chill has little meaning.

Check the temp in the morning. Predictions are often off by enough to invalidate my clothing choices.

Yeah, we're always subject to windchill when riding but windproof clothing pretty much eliminates that anyway :D I just look in the morning what my outdoor thermometer says and dress accordingly.

At first you will over-dress and under-dress several times before you get the feel for it.

Adam

I dunno about that, it does have some effect. today going down the hill into the wind, I felt a lot colder, particularly the less covered parts, like bits of my face. When I turned around for the other leg, going up hill, i got quite sweaty. So, if you have significant changes of direction, going into the wind can have an effect. It depends on exactly how your route direction goes with or against the wind, i would say. You're wearing windproof clothing yes, but the wind is still going across the body, taking away more heat. It's not the same as someone standing around, or walking, but it does need to be taken into consideration.

Yes, face, hands and feet will get much colder in the wind but for the torso and the legs it shouldn't be that much different - unless you're wearing side or back ventilated jacket then the cold wind will force itself inside. Also, since you lose something like 60% (or more?) of body heat through your head and neck I find wearing a balaclava plus a warm skull cap makes me feel warmer overall.

Adam

I joke with a coworker that "Wind chill is for wimps," for the reasons cited. I have a Temperature-Dress chart in 10 degree F intervals that I use for the current temp. However, last week at 30 degrees, I did not wear a face mask, as according to my chart, but with an unusually strong cross wind of about 30 mph, I did need it. I fortunately brought it along and put it on about a half mile into my ride.

I did admit to my co-worker that I "wimped out." :lol: :o

The wind will definitely have a cooling convective effect since it will blow the layer of slightly warmer air away from the exterior of your wind resistant shell, but it isn't appropriate to use those wind-chill/feels-like calculations when you're mostly protected and insulated from the wind.

For example it was -24C windchill sat morning but only -12C temperature and having been oustide at -24C on a bike before i can tell you it felt nowhere near as cold as the windchill calculation told me it should feel.

You're losing heat off your body and that heat loss accelerates with the wind speed. Having all exposed skin covered really reduces the wind's bite but doesn't eliminate the chilling effect completely. So while I don't actually dress for the "feels like" temp, high winds can influence what I wear. For example, I typically don't put the ski goggles on until it gets below 0 F. But if it's 7 and really windy, I'll probably be sporting the goggles.

Wind also increases the airflow around my torso and the drafts sneaking up the gaps in my layers at the waist. So I make sure I have my amfib bibs on when it's windy.

fyi, - "Scientists debunk the myth that you lose most heat through your head"
http://www.guardian.co.uk/science/20...humanbehaviour

Also, I think I may not have explained myself very about about windchill. It's not that the wind can't affect you, it's that I find it nearly impossible to figure out how it will affect you. It's somewhat easier to calculate windchill if you're standing still, though it still depends on if you're exposed to the wind or have stuff blocking it, etc.

But on the bike - I've just found it impossible to determine. If there's a decent wind, but you're traveling with the wind, you can actually be warmer than if there was no wind. If you're going into the wind, it's definitely colder. And which way it is can change dramatically as you bike - one minute you're biking with a sidewind, the next minute you take a turn and you're going into the wind. Later you're shielded from the wind...

I'm not trying to say the wind won't affect you, but I've found it's nearly impossible to determine exactly how it's going to affect me unless I happen to be on some sort of east-west route that's exposed to the wind with no turns. Which is...nearly impossible.

It my case it's pretty easy to know how it's going to affect me. Work is N-NW of where I live so most of my commute I'm either traveling North, West, or both. On about 1/2 of my commute I'm fairly exposed to the wind. Winter winds around here, especially on extra cold days, are often out of the North and/or West so that means a headwind going into work. That's also the time of the day when temps are typically at their lowest.

My basic winter garb is good from about 0 to 25 F though I'll often start making some changes as it gets down into the low single digits. A windy day means I might start reaching for the more extreme gear at 8 degrees instead of 2. A real windy day means I might have my most extreme winter gear on at -5 instead of -15.

There's nothing hard and fast but I do know that if I ignore the wind when considering my clothing choices, I can end up being awfully miserable.

Once I get downtown the wind direction can change depending on what street I'm on, but that's a short part of my journey.

A simple IR image of unclothed human body will debunk the above debunking:D The head is the hottest part of the body at any given time.

"If as much as 45 percent of body heat were lost through your head, going out without a hat would feel like going out without trousers". That's not the point, that sentence is silly, it's not about how one "feels" but how much total energy is lost from the body. You feel colder without trousers because larger area of your skin is exposed (more nerve endings are screaming "cold!"), but that doesn't mean you're losing more heat this way. And you're more likely to get frost bite on exposed limbs, because they're colder than your head. Your brain is the most power hungry organ, it alone consumes something like 20%-25% of your total body energy.

Adam

Temperature, wind speed, and wind DIRECTION (as a function of which way I'm headed).

I've had some serious overheats dressing for a windchill and getting a tailwind.

Well, we could go back and forth, but I'm sure it would just turn into one of those pseudo-technical back and forth's where no one can really "prove" anything. I mean, it's not like I'm going to "simply" pull out my IR imager, then follow it up with a double blind study of my own, lol.

Nonetheless, I feel compelled to link to this, which when you consider the small size of the head compared to the 40% figure, seems entirely possible when there's no wind for someone who's acclimated to the cold, lol -
http://wow-really.blogspot.com/2006/...ough-your.html

http://bikeforums.net/attachment.php...hmentid=131242

If you dress properly for the actual temperature and conditions, the 'feels like' temp feels like the worthless, media hype that it is. ;)

LOL, see? He keeps warm because he has a hat on!!!!

I saw a guy on a cruiser bike wearing shorts and a leather vest only last Thursday on my way home. It was mid 20s.

Adam

I was thinking about this today on my ride in at 23 F degrees . The wind was almost a dead calm at 3 mph and I was thinking how much more uncomfortable it might be with strong winds across my face and body. when I dress, I do look at the predicted wind speed, but not to the point where I plan on the wind-chill being the temperature to dress for. riding in 15-20 mph wind (regardless of direction) would have changed the experience. I was a little over-dressed today but my eyes were comfortable uncovered. if it were a windy day I would have probably missed the eyewear.

Lol, my point was that you don't see that kind of thing happen - a guy outside shoveling with no shirt (well, a tshirt more likely) and a warm, big-ass hat on like you would if you lost 40-60% of your body heat through your head. I mean, if I could really stay warm by just insulating my head more, you would *definitely* see me out on the slopes in a tshirt at 25 degrees with a giant hat on. :-)

I think it was a month ago that I had on all my waterproof, windproof gear on and was thinking about how cold it was when I passed a guy wearing shorts. Shorts! And my friends call *me* hardcore, lol. Was the guy with the vest wearing a giant hat? :-)

I wonder how much of the heat that you lose through your head is coming out of your nose and mouth. ;)

Seriously, it's got to be a good chunk of it. Dogs get rid of a lot of heat that way. Of course most of them have bigger mouths.

Nope. Not even a helmet :rolleyes: I wonder if perhaps something kept him warm "internally"? Or perhaps he was one of those guys who swim in the ocean in Winter?

Yup. Therefore the fogging problem :D

A.

Split the difference.

Pay attention if there's a significant delta between actual temperature and "Real Feel" (i.e., 10° or more), otherwise figure that whatever extra coldification is due to the wind (either self-generated or otherwise) will be offset by the heatification you create via physical exertion.

I check the hourly forecast in the evening, but my ultimate decision on how to dress is based on sticking my head out the window in the morning.

The problem with the temp only approach is that it does not take into account other factors which have an effect on your heat loss. Things such as is the ground frozen, very bright and sunny, wind chill, length of ride, risk. Light rain, etc.

It's generally better to use the "feels like" appproach. Both for comfort and for safety. However, it should be your own personal "feels like" from experience. Not the one you hear on the news because everyone has different metabolism and insulation needs.

I think that has more to do with going up and downhill than it does the wind. My ride home is more downhill than uphill and I warm up quickly when I encounter the climbs.