Wet Bulb Dry Bulb Humidity Calculator

Note that continuously air flow around the thermometer is important to evaporate.

Wet bulb dry bulb humidity calculator.

Enter your actual station pressure not the altimeter setting. Enter the two different temperatures. Wet bulb temp c. To calculate relative humidity in percent hereinafter denoted as rh from dry bulb temperature t and wet bulb temperature t w one can use a well known set of forward analytical psychrometric equations bohren and albrecht 1998.

Relative humidity dewpoint temp c. The wet bulb temperature might not be a widely known measure but it has some valuable functions. Snowmaking snow production needs low temperatures and when the humidity decreases the temperature rises. The calculator will show the saturation mixing ratio in grams of water per kilogram of dry air of a given temperature if the dry and wet bulb temperatures are set to the same value.

Dry bulb temperature t db can be measured with a simple thermometer as shown above. If the air is fully saturated 100 relative humidity the water cannot evaporate so both the wet and dry bulb temperatures are the same. Construction different materials react differently to different humidities so this temperature is needed when designing a building in different climates. Calculate dewpoint wet bulb temperature from relative humidity.

Wet bulb temperature t wb can be measured with a standard thermometer with some wet clothing cotton or similar around the bulb. Dry bulb temp c. There is a converter below this calculator if you only know the celsius temperature for the entries required. Enter a temperature relative humidity and actual station pressure.

Dewpoint is the atmospheric temperature below which water droplets begin to condense and become dew. This script will determine the relative humidity from the entered dry and wet bulb temperatures data. Altitude above sea level m. If the air is fully saturated 100 relative humidity the water cannot evaporate so both the wet and dry bulb temperatures are the same.

Enter dry bulb temperature plus either wet bulb temp rh or dewpoint temp. Relative humidity is measured using a device called a sling psychrometer this consists of 2 side by side conventional thermometers one of which the wet bulb thermometer has a wetted wick placed at the bottom the other the dry bulb thermometer has no wetted wick. When the psychrometer is swung around by its attached chain or handle the air causes the water on the wick to evaporate which. A simple online weather calculator to find the dewpoint and the wet bulb temperature by knowing the values of relative humidity temperature and actual station pressure.

If the dry and wet bulb temperatures are set to the same value the calculator will show the saturation mixing ratio the amount of water in saturated air at that temperature. Air humidity can be estimated by measuring. Stull 2011 for any pressure such as standard sea level pressure of 101 325 kpa the resulting calculated values of rh can be listed in psychrometric tables.