heat.index.algorithm {weathermetrics}

Algorithm for heat.index function.

Description

heat.index.algorithm converts a numeric scalar of temperature (in Fahrenheit) and a numeric scalar of relative humidity (in %) to heat index (in Fahrenheit). This function is not meant to be used outside of the heat.index function.

Usage

heat.index.algorithm(t = NA, rh = NA)

Arguments

t

Numeric scalar of air temperature, in Fahrenheit.

rh

Numeric scalar of relative humidity, in %.

Details

If an impossible value of relative humidity is given (below 0% or above 100%), heat index is returned as NA.

Value

A numeric scalar of heat index, in Fahrenheit.

Note

Equations are from the source code for the US National Weather Service's online heat index calculator.

Author(s)

Brooke Anderson [e-mail], Roger Peng [e-mail]

References

Anderson GB, Bell ML, Peng RD. 2013. Methods to calculate the heat index as an exposure Metric in environmental health research. Environmental Health Perspectives 121(10):1111-1119.

National Weather Service Hydrometeorological Prediction Center Web Team. Heat Index Calculator. 30 Jan 2015. http://www.wpc.ncep.noaa.gov/html/heatindex.shtml. Accessed 18 Dec 2015.

Rothfusz L. 1990. The heat index (or, more than you ever wanted to know about heat index) (Technical Attachment SR 90-23). Fort Worth: Scientific Services Division, National Weather Service.

R. Steadman, 1979. The assessment of sultriness. Part I: A temperature-humidity index based on human physiology and clothing science. Journal of Applied Meteorology, 18(7):861–873.

See Also

heat.index