# humidity.to.dewpoint: Calculate dew point temperature. In weathermetrics: Functions to Convert Between Weather Metrics

## Description

`humidity.to.dewpoint` creates a numeric vector of dew point temperature from numeric vectors of air temperature and relative humidity.

## Usage

 `1` ```humidity.to.dewpoint(rh = NA, t = NA, temperature.metric = "fahrenheit") ```

## Arguments

 `rh` Numeric vector of relative humidity (in %). `t` Numeric vector of air temperatures. `temperature.metric` Character string indicating the temperature metric of air temperature. Possible values are `fahrenheit` or `celsius`.

## Details

Dew point temperature will be calculated in the same metric as the temperature vector (as specified by the `temperature.metric` option). If you'd like dew point temperature in a different metric, use the function `celsius.to.fahrenheit` or `fahrenheit.to.celsius` on the output from this function.

## Value

A numeric vector of dew point temperature, in the same metric as the temperature vector (as specified by the `temperature.metric` option).

## Note

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

## Author(s)

Brooke Anderson [email protected], Roger Peng [email protected]

## References

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.

```dewpoint.to.humidity, fahrenheit.to.celsius, celsius.to.fahrenheit```
 ```1 2 3 4 5 6 7 8``` ```# Calculate dew point temperature from relative humidity and # air temperature. data(newhaven) newhaven\$DP <- humidity.to.dewpoint(t = newhaven\$TemperatureF, rh = newhaven\$Relative.Humidity, temperature.metric = 'fahrenheit') newhaven ```