Comparison of Phase 0 and Phase 2 Storm Conditions
The two pictures below were provided by Capt Andrew Webster, crew commander at the Ballistic Missile Early Warning System Site (Dec. 1996 - Dec. 1997). The pictures are taken out the same window of the officers' quarters during no storm and a Phase 2 storm.
No Storm ("phase 0") Conditions Compared to Phase 2
Below is after the Phase 2 storm. The reason snow is not stacked up is that there is very little snow fall at Thule. Mostly there are just ice crystals blowing horizontally at high wind velocity and extreme low temperature. Not much ice sticks to anything because it is so very dry and frozen very hard in the very low temperature.
Below is a "Phase 2" storm. And it gets much worse. In a Phase 3, if you were able to stand and if you were able to open your eyes without them freezing shut, you would not be able to see your feet.
Explanation of Wind Chill Factor
When the temperature is low (-20F to -30F) and the wind speed is high (100 mph and more) the wind chill factor can create an extremely low effective temperature on the skin.
The wind chill factor affects how cold people and animals feel under conditions of cold temperature plus wind. Wind chill is based on the rate of heat loss from exposed skin. As the wind speed increases, it draws more heat from the exposed skin and drives down the skin temperature. Therefore, the wind makes it FEEL much colder than the actual air temperature. For example, if the air temperature is 0 degrees Fahrenheit and the wind is blowing at 15 mph, the windchill is -19 degrees Fahrenheit. At this windchill temperature, exposed skin can freeze in 30 minutes. In winter at Thule, this is a frequent outdoors condition. During one storm during the time I was at Thule the wind chill temperature was -110F!
The windchill temperature is calculated using the following formula:
Windchill (ºF) = 35.74 + 0.6215T - 35.75(V^0.16) + 0.4275T(V^0.16)
Where: T = Air Temperature (F)
V = Wind Speed (mph) ^ = raised to a power (exponential)
Windchill Temperature is only defined for temperatures at or below 50 degrees F and wind speeds above 3 mph. Bright sunshine may increase the windchill temperature by 10 to 18 degrees F.
The only effect windchill has on inanimate objects, such as car radiators and water pipes, is to more quickly cool the object to cool to the current air temperature. Inanimate object will NOT cool below the actual air temperature. For example, if the temperature outside is -15 degrees Fahrenheit and the windchill temperature is -41 degrees Fahrenheit, then your car's radiator will not drop lower than -15 degrees F.