feels

feels

Feels allow you to calculate apparent temperature using heat index, approximate wet-bulb globe temperature, humidex, australian apparent temperature and wind chill.

Combinations of this methods also named as Feels like, Real feel etc.

You can also convert temperature, speed and calculate relative humidity, dew point, frost point, water vapour pressure using class or standalone methods.

Usage

$ npm install feels --save

const Feels = require('feels');

const config = {
  temp: 20,
  humidity: 85,
  speed: 20,
  units: {
    temp: 'c',
    speed: 'mps'
  }
};

new Feels(config).like();

Quick navigation

• Class methods
  • .setOptions(options)
  • .like([methods])
  • .addMethod(name, method)
  • .registerMethod(method)
  • .registerMethods(methods)
  • .heatIndex()
  • .AWBGT()
  • .humidex()
  • .AAT()
  • .windChill()
  • .getWVP()
  • .getWVPbyDP()
  • .getARH()
  • .getRH()
  • .getADP()
  • .getDP()
  • .getFP()
• Standalone methods
  • Temperature convert
  • Speed convert
  • Heat index
  • Approximate WBGT
  • Humidex
  • Australian Apparent Temperature
  • Wind chill
  • Water vapour pressure
  • Approximate relative humidity
  • Relative humidity
  • Approximate dew point
  • Dew point
  • Frost point

API

Class methods

Most of the class methods also available as standalone methods.

new Feels(options)

Constructor.

Params:

• options (Object) - Feels options:
  • temp (Float) - Temperature in Celsius, Fahrenheit or Kelvin, depends on units type.
  • humidity (Float) - Relative humidity in percent.
  • speed (Float) - Wind speed in meters per second, miles per hour or kilometers per hour, depends on units type.
  • dewPoint (Float) - Dew point in Celsius, Fahrenheit, Kelvin depends on units type.
  • wvp (Float) - Water vapour pressure in hPa.
  • units (Object) - Units type:
    • temp (String) - c, f, k (by default c).
    • speed (String) - mps, mph, kph (by default mps).

const Feels = require('feels');

new Feels({ temp: 20, humidity: 80.9 }).toF().humidex();

.setOptions(options)

Sets the options.

Params:

• options (Object) - Feels options:
  • temp (Float) - Temperature in Celsius, Fahrenheit or Kelvin, depends on units type.
  • humidity (Float) - Relative humidity in percent.
  • speed (Float) - Wind speed in meters per second, miles per hour or kilometers per hour, depends on units type.
  • dewPoint (Float) - Dew point in Celsius, Fahrenheit, Kelvin depends on units type.
  • wvp (Float) - Water vapour pressure in hPa.
  • units (Object) - Units type:
    • temp (String) - c, f, k (by default c).
    • speed (String) - mps, mph, kph (by default mps).

const Feels = require('feels');
const feels = new Feels();
const config = {
  temp: 20,
  humidity: 85,
  speed: 20,
  units: {
    temp: 'c',
    speed: 'mps'
  }
};

feels.setOptions(config);
feels.AAT();

.like([methods])

Calculates apparent temperature using specified methods.

If methods aren't provided returns an index which is calculated with ['HI', 'HI_CA', 'AAT', 'WCI'].

Params:

• [methods] (String|Array) - String or array with one of the apparent temperature acronyms.

Acronyms

• HI - Heat index (Feels().heatIndex() or heatIndex()).
• AWBGT - Approximate wet-bulb globe temperature (Feels().AWBGT() or AWBGT()).
• HI_CA - Humidex (Feels().humidex() or humidex()).
• AAT - Australian apparent temperature (Feels().AAT() or AAT()).
• WCI - Wind chill (Feels().windChill() or windChill()).

If you want to convert temperature from one to other temperature scale, you can place .toC(), .toF() or .toK() before target method.

new Feels(config).toF().like(['AAT', 'HI_CA']);

.addMethod(name, method)

Adds new method, which can be used by itself or in .like().

Params:

• name (String) - Method name.
• method (Function) - The method itself.

const feels = new Feels();
feels.addMethod('newbie', () => (feels.heatIndex() + feels.humidex()) / 2);
feels.addMethod('newbie2', function () {
  return (this.heatIndex() + this.humidex()) / 2;
});

feels.setOptions({ temp: 20, dewPoint: 18 });
feels.newbie();
feels.like(['AAT', 'newbie2']);

.registerMethod(method)

Params:

• method (String) - Method name.

.registerMethods(methods)

Allows you to create your own methods which can be used in .like(), by inheriting the base class.

Params:

• methods (Array) - Method names.

class NewFeels extends Feels {
  constructor(opts) {
    super(opts);
    this.registerMethods(['newbie', 'newbie2']);
  }
  newbie() {
    return (this.heatIndex() + this.humidex()) / 2;
  }
  newbie2() {
    return (this.heatIndex() + this.humidex()) / 2;
  }
}

const feels = new NewFeels({ temp: 20, dewPoint: 18 });

feels.newbie();
feels.like(['AAT', 'newbie2']);

.heatIndex()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity|dewPoint (Float)

.AWBGT()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity|dewPoint (Float)

.humidex()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity|dewPoint (Float)

.AAT()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • speed (Float)
  • humidity|dewPoint (Float)

.windChill()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • speed (Float)

.getWVP()

Params:

• options (Object) - Constructor options:
  • humidity (Float)
  • temp (Float)

.getWVPbyDP()

Params:

• options (Object) - Constructor options:
  • dewPoint (Float)

.getARH()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • dewPoint (Float)

.getRH()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • wvp|dewPoint (Float)

.getADP()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity (Float)

.getDP()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity (Float)

.getFP()

Params:

• options (Object) - Constructor options:
  • temp (Float)
  • humidity (Float)

Aliases

• toC() - toCelsius()
• toF() - toFahrenheit()
• toK() - toKelvin()
• getWVP() - getWaterVapourPressure()
• getWVPbyDP() - getWaterVapourPressureByDewPoint()
• getARH() - getAproximateRelativeHumidity()
• getRH() - getRelativeHumidity()
• getADP() - getAproximateDewPoint()
• getDP() - getDewPoint()
• getFP() - getFrostPoint()

Standalone methods

All standalone methods use temperature in Celsius, humidity in percent and wind speed in meters per second.

const Feels = require('feels');

Feels.humidex(20, 80.9);

Temperature convert

Feels.tempConvert(temp, from, to)

Params:

• temp (Float) - Temperature.
• from (String) - c - Celsius, f - Fahrenheit, k - Kelvin.
• to (String) - c - Celsius, f - Fahrenheit, k - Kelvin.

const Feels = require('feels');
const humidex = Feels.humidex(20, 80.9);

Feels.tempConvert(humidex, 'c', 'f');

Speed convert

Feels.speedConvert(speed, from, to)

Params:

• speed (Float) - Speed.
• from (String) - mps - Metre per second, mph - Miles per hour, kph - Kilometre per hour.
• to (String) - mps - Metre per second, mph - Miles per hour, kph - Kilometre per hour.

const Feels = require('feels');
const speed = Feels.speedConvert(36, 'kph', 'mps');

Feels.AAT(20, speed, 89);

Heat index

The heat index is an index that combines air temperature and relative humidity in an attempt to determine the human-perceived equivalent temperature. Wiki

Note: The heat index is used for temperatures more than 20 Celsius.

Feels.heatIndex(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Feels.heatIndex(temp, dewPoint, true)

Params:

• temp (Float) - Temperature in Celsius.
• dewPoint (Float) - Dew point in Celsius.
• true (True) - Must be true for dew point usage.

Approximate WBGT

The approximate wet-bulb globe temperature is a composite temperature used to estimate the effect of temperature, humidity, wind speed on humans. Unlike WBGT, AWBGT not take into account radiation effect. Wiki

Note: The AWBGT is used for temperatures more than 15 Celsius.

Feels.AWBGT(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Feels.AWBGT(temp, dewPoint, true)

Params:

• temp (Float) - Temperature in Celsius.
• dewPoint (Float) - Dew point in Celsius.
• true (True) - Must be true for dew point usage.

Humidex

The humidex is an index number used by Canadian meteorologists to describe how hot the weather feels to the average person, by combining the effect of heat and humidity. Wiki

Note: The humidex is used for temperatures more than 0 Celsius.

Feels.humidex(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Feels.humidex(temp, dewPoint, true)

Params:

• temp (Float) - Temperature in Celsius.
• dewPoint (Float) - Dew point in Celsius.
• true (True) - Must be true for dew point usage.

Australian Apparent Temperature

The AAT is an index number used by the Australian Bureau of Meteorology to describe heat balance in the human body. Wiki

Feels.AAT(temp, speed, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• speed (Float) - Speed in meters per second.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Feels.AAT(temp, speed, dewPoint, true)

Params:

• temp (Float) - Temperature in Celsius.
• speed (Float) - Speed in meters per second.
• dewPoint (Float) - Dew point in Celsius.
• true (True) - Must be true for dew point usage.

Wind chill

Wind chill is the perceived decrease in air temperature felt by the body on exposed skin due to the flow of air. Wiki

Note: The humidex is used for temperatures less than 0 Celsius.

Feels.windChill(temp, speed)

Params:

• temp (Float) - Temperature in Celsius.
• speed (Float) - Speed in meters per second.

Water vapour pressure

Feels.getWVP(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Feels.getWVPbyDP(dewPoint)

Params:

• dewPoint (Float) - Dew point in Celsius.

Approximate relative humidity

Feels.getARH(temp, dewPoint)

Params:

• temp (Float) - Temperature in Celsius.
• dewPoint (Float) - Dew point in Celsius.

Relative humidity

Feels.getRH(temp, WVP)

Params:

• temp (Float) - Temperature in Celsius.
• WVP (Float) - Water vapour pressure.

Feels.getRH(temp, dewPoint, true)

Params:

• temp (Float) - Temperature in Celsius.
• dewPoint (Float) - Dew point in Celsius.
• true (True) - Must be true for dew point usage.

Approximate dew point

Feels.getADP(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Dew point

Feels.getDP(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

Frost point

Feels.getFP(temp, humidity)

Params:

• temp (Float) - Temperature in Celsius.
• humidity (Integer) - Humidity in percent (0 > humidity <= 100).

License

The MIT License (MIT)
Copyright (c) 2015-2016 Alexey Bystrov