When the wind comes sweeping down the plain this winter, the “wind chill” readings from the National Weather Service won’t be quite so low. The Weather Service is changing the formula for calculating the wind chill factor. Meteorologist Brad Small works at the National Weather Service office in Johnston, Iowa.Small says the new formula is based on how the wind actually feels to exposed human skin. Measurements taken at 33 feet in the air will be adjusted to how the wind feels at five feet.Small says new computer software will be installed in National Weather Service computers to make the new “wind chill” calculations.Small says “wind chill” advisories and warnings may be adjusted to account for the “warmer” readings. The old charts for computing the wind chill were based the rate at which water froze during research experiments conducted in Antarctica in 1945. Under the old system, if the temperature was five degrees above and the wind was blowing at 20 miles per hour, the wind chill factor was 30 below. Under the new system, the wind chill will be in the 10 to 15 degree range.