Cloud Altitude Calculator: Understanding Cloud Base Height

What is Cloud Base Height?

Cloud base height, also known as cloud altitude, is the height above the Earth's surface at which clouds begin to form. It's a crucial parameter in meteorology, aviation, and weather forecasting. The cloud base height is where the air temperature cools to its dew point, causing water vapor to condense into visible cloud droplets.

Formula and Variables

The simplified formula for estimating cloud base height is:

\[H = (T - T_d) \times 125\]

Where:

• \(H\) is the cloud base height (in meters)
• \(T\) is the surface air temperature (in °C)
• \(T_d\) is the surface dew point temperature (in °C)
• 125 is a constant representing the approximate meters of altitude per degree Celsius of spread

Calculation Steps

1. Measure the surface air temperature and dew point temperature.
2. Ensure both temperatures are in Celsius.
3. Calculate the difference between air temperature and dew point (spread).
4. Multiply this difference by 125 to get the height in meters.
5. Convert to desired units if necessary (e.g., feet).

Example and Visual Representation

Let's calculate the cloud base height with:

• Air Temperature: 25°C
• Dew Point: 15°C

\[H = (25°C - 15°C) \times 125 = 10 \times 125 = 1,250 \text{ meters}\]

This diagram illustrates the concept of cloud base height. The brown line represents the ground, the blue area is the atmosphere, and the white shape represents the cloud base. The dashed line indicates the altitude where the air temperature has cooled to the dew point, forming the cloud base at 1,250 meters above ground level.