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'''Wind chill''' is the apparent temperature felt on exposed skin due to wind. The degree of this phenomenon depends on both air temperature and wind speed. The wind chill temperature (often popularly called the wind chill factor) is always lower than the air temperature. In cases where the apparent temperature is higher than the air temperature, the [[heat index]] is used instead.
'''Wind chill''' is the apparent temperature felt on exposed skin due to wind.
*The degree of this phenomenon depends on both air temperature and wind speed. The greatest wind chill reported in extremes, results from a combination of a low temperature and a high wind speed.
*The wind chill temperature (often popularly called the wind chill factor) is always lower than the air temperature. In cases where the apparent temperature is higher than the air temperature, the [[heat index]] is used instead.


Some weather stations provide a Wind Chill reading and, by default, that reading will be used by Cumulus.
#If within Cumulus you apply corrections (Configuration menu, ''Calibration'' screen) to either temperature or wind speed, then any wind chill output by your station will not be compatible, and you should set Cumulus to ''Calculate Wind Chill''.
#On Configuration menu click '''Station''' and tick the option to ''Calculate Wind Chill''.
*There may be other reasons why you do not want to use the reading provided by your station and tick this option.
*If your weather station does not provide a Wind Chill reading, Cumulus will calculate it (regardless of whether the option is ticked or not).


Wind chill Temperature is only defined for temperatures at or below 10 °C (50 °F) and wind speeds above 4.8 kilometres per hour (3.0 mph).
Wind Chill Temperature is officially defined for temperatures at or below 10 °C (50 °F) and wind speeds above 4.8 kilometres per hour (3.0 mph).
*For lower wind speeds, Cumulus will report a wind chill temperature that will be the same as reported for temperature.
*By default, for higher temperatures, Cumulus will report a wind chill temperature that will be the same as reported for temperature. Cumulus can make a wind chill calculation for temperatures above 10°C, so if you have asked Cumulus to calculate wind chill and don't wish it to comply with the ten degree limit, edit your [[cumulus.ini]] and add to the [[Cumulus.ini_(Cumulus_1)#Section:_Station|''[Station]'']] section the line: <pre>UseWindChillCutoff=0</pre>


More information on Wind Chill [https://en.wikipedia.org/wiki/Wind_chill#North_American_and_United_Kingdom_wind_chill_index here in Wikipedia]. Cumulus uses the 'new North American' formula, as described on that page. For a discussion on the usefullness of wind chill in Canada see [https://www.aweathermoment.com/wind-chill here].


[[Category:Terminology]]
Some weather stations provide a Wind Chill reading and this will be used by Cumulus, however if one is not provided Cumulus can calculate the Wind Chill. Click Configuration, Station and tick the option to Calculate Wind Chill.


By default Cumulus will provide a Windchill reading for temperatures above 10°C, however if you wish wish to comply with the ten degree limit, edit your [[cumulus.ini]] and add the line <pre>UseWindChillCutoff=1</pre>


More information on Wind Chill [http://en.wikipedia.org/wiki/Wind_chill here]

Latest revision as of 16:24, 22 March 2021

Wind chill is the apparent temperature felt on exposed skin due to wind.

  • The degree of this phenomenon depends on both air temperature and wind speed. The greatest wind chill reported in extremes, results from a combination of a low temperature and a high wind speed.
  • The wind chill temperature (often popularly called the wind chill factor) is always lower than the air temperature. In cases where the apparent temperature is higher than the air temperature, the heat index is used instead.

Some weather stations provide a Wind Chill reading and, by default, that reading will be used by Cumulus.

  1. If within Cumulus you apply corrections (Configuration menu, Calibration screen) to either temperature or wind speed, then any wind chill output by your station will not be compatible, and you should set Cumulus to Calculate Wind Chill.
  2. On Configuration menu click Station and tick the option to Calculate Wind Chill.
  • There may be other reasons why you do not want to use the reading provided by your station and tick this option.
  • If your weather station does not provide a Wind Chill reading, Cumulus will calculate it (regardless of whether the option is ticked or not).

Wind Chill Temperature is officially defined for temperatures at or below 10 °C (50 °F) and wind speeds above 4.8 kilometres per hour (3.0 mph).

  • For lower wind speeds, Cumulus will report a wind chill temperature that will be the same as reported for temperature.
  • By default, for higher temperatures, Cumulus will report a wind chill temperature that will be the same as reported for temperature. Cumulus can make a wind chill calculation for temperatures above 10°C, so if you have asked Cumulus to calculate wind chill and don't wish it to comply with the ten degree limit, edit your cumulus.ini and add to the [Station] section the line:
    UseWindChillCutoff=0

More information on Wind Chill here in Wikipedia. Cumulus uses the 'new North American' formula, as described on that page. For a discussion on the usefullness of wind chill in Canada see here.