Wind Chill Table
How to use this table
I created this table to help you understand the dangers of hypothermia and frostbite when riding a motorcycle. I was disappointed that most windchill charts start at a temperature not much above freezing. Since we've all noticed that there is an appreciable windchill at temperatures many would consider normal I thought that starting at a warmer temperature would be worthwhile.
I used the official formula that everyone else was using to create their windchill charts. That formula, if you are interested is listed below the chart. I also have the chart in an Excel 97 spreadsheet. If you need a copy of it I could be persuaded to email it to you.
One of the things I noticed is that at 100 degrees F the wind offers no relief at all. Some Iron Butt Association members lead me to believe that this is accurate. When crossing desert portions of the country it is cooler, they tell me, to keep your skin covered by a jacket. Apparently the insulating qualities work to keep the excess heat out much the same way it keeps heat in during colder temperatures. Or maybe it was just keeping the sun off that helped. I don't begin to claim I know the exact cause why. I only present it as anecdotal evidence.
Another interesting characteristic that this chart points out is that it is true that above 40 mph the temperatures seem to stabilize. Then they actually increase a bit with the rise in wind speed. Is that accurate? Again, I don't know. Maybe it is. Looking at the formula, it is rather complex. Someone stayed up late figuring that one out. My belief is that it really doesn't matter because the difference is not very great. Even at the coldest extremes there's only an eight degree difference. And when you're feeling -95F can you really tell the difference between that and -103F. I probably couldn't.
I hope you find this useful.
JP Honeywell
| Wind speed (in mph) |
still air temperature (degrees F) |
| 100 |
90 |
80 |
70 |
60 |
50 |
40 |
30 |
20 |
10 |
0 |
-10 |
-20 |
-30 |
| wind chill temperature |
| 0 |
100 |
90 |
80 |
70 |
60 |
50 |
40 |
30 |
20 |
10 |
0 |
-10 |
-20 |
-30 |
| 5 |
100 |
90 |
79 |
69 |
58 |
48 |
37 |
27 |
16 |
6 |
-5 |
-15 |
-26 |
-36 |
| 10 |
102 |
90 |
77 |
65 |
53 |
41 |
28 |
16 |
4 |
-9 |
-21 |
-33 |
-46 |
-58 |
| 15 |
103 |
90 |
76 |
63 |
49 |
36 |
22 |
9 |
-4 |
-18 |
-31 |
-45 |
-58 |
-72 |
| 20 |
104 |
89 |
75 |
61 |
47 |
33 |
18 |
4 |
-10 |
-24 |
-39 |
-53 |
-67 |
-81 |
| 25 |
104 |
89 |
75 |
60 |
45 |
30 |
15 |
1 |
-14 |
-29 |
-44 |
-59 |
-73 |
-88 |
| 30 |
104 |
89 |
74 |
59 |
44 |
28 |
13 |
-2 |
-17 |
-32 |
-48 |
-63 |
-78 |
-93 |
| 35 |
105 |
89 |
74 |
58 |
43 |
27 |
12 |
-4 |
-19 |
-35 |
-51 |
-66 |
-82 |
-97 |
| 40 |
105 |
89 |
73 |
58 |
42 |
26 |
10 |
-5 |
-21 |
-37 |
-53 |
-68 |
-84 |
-100 |
| 45 |
105 |
89 |
73 |
57 |
42 |
26 |
10 |
-6 |
-22 |
-38 |
-54 |
-70 |
-86 |
-101 |
| 50 |
105 |
89 |
73 |
57 |
41 |
25 |
9 |
-7 |
-23 |
-39 |
-55 |
-71 |
-86 |
-102 |
| 55 |
105 |
89 |
73 |
57 |
41 |
25 |
9 |
-7 |
-23 |
-39 |
-55 |
-71 |
-87 |
-103 |
| 60 |
105 |
89 |
73 |
57 |
41 |
25 |
9 |
-7 |
-23 |
-39 |
-55 |
-71 |
-87 |
-102 |
| 65 |
105 |
89 |
73 |
57 |
41 |
26 |
10 |
-6 |
-22 |
-38 |
-54 |
-70 |
-86 |
-102 |
| 70 |
105 |
89 |
73 |
58 |
42 |
26 |
10 |
-6 |
-21 |
-37 |
-53 |
-69 |
-85 |
-101 |
| 75 |
105 |
89 |
74 |
58 |
42 |
26 |
11 |
-5 |
-21 |
-36 |
-52 |
-68 |
-83 |
-99 |
| 80 |
105 |
89 |
74 |
58 |
43 |
27 |
12 |
-4 |
-19 |
-35 |
-50 |
-66 |
-81 |
-97 |
| 85 |
105 |
89 |
74 |
59 |
43 |
28 |
13 |
-3 |
-18 |
-33 |
-49 |
-64 |
-79 |
-95 |
| |
| Note: Wind speeds greater than 40mph add little to the effect |
| |
|
|
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| No protection required |
Little danger if properly clothed |
Increasing Danger of freezing exposed skin |
Great Danger of freezing exposed skin |
| Formula used to calculate Wind chill
Wind chill = 91.4 - (0.474677 - 0.020425 * W + 0.303107 * SQRT(W)) * (91.4 - T)
where W = wind speed (mph)
and
T = temperature (° F)
|
- Frostbite: Is the crystallization of tissue fluid cased by exposure to cold below freezing. Most common areas of frostbite are the face, nose, ears, hands and feet. The symptoms include redness and pain in the early stages, followed by a waxy white appearance, numbness and the skin may feel stiff and even brittle.
- PREVENTION OF COLD INJURY
- To Stay Warm Remember The Word C-O-L-D
- C - Cleanliness and Care: Feet, Socks, and clothing are warmer when clean. Constant foot care is imperative.
- O - Overheating: Prevent overheating by adjusting your clothing to the job being performed.
- L - Loose and Layered: Loose-fitting clothing insures good circulation and insulation. Clothing in layers assures air spaces which hold body heat. Again, allows the person to adjust the number of layers to the temperature and activity being performed.
- D - Dampness: Any wet garment is a cold garment, just as tight-fitting garments are cold producing garments. Keep clothing dry.
- * Use the Buddy system, this is the best way to prevent cold injury. If you start feeling cold do some exercises until you start feeling warm again.
FIRST AID FOR COLD INJURIES
- Get individual off their feet.
- Get individual into warm dry clothing.
- Get individual warm fluids to drink (NO ALCOHOLIC BEVERAGES)
- Do not smoke.
- Keep the effected area clean, warm and dry. Do not allow to REFREEZE. If you cannot keep area warm, leave it frozen.
- Do not rub effected area.
- Evacuate through medical channels ASAP.
- HYPOTHERMIA
- The condition of low internal body heat dropping steadily from a healthy 98.6, and if not reversed, can bring fatal consequences. Hypothermia can develop without much warning. Dress for the weather and avoid getting wet or damp.
- Generally characterized by uncontrolable shivering, mild hypothermia can be treated by drinking warm liquids, and by taking a hot shower. A more serious condition requires medical attention.
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