Enter the number of forecast models predicting rain and the total number of forecast models used into the calculator to determine the rain probability. This calculator can also evaluate any of the variables given the others are known.

## Rain Probability Formula

The following formula is used to calculate the rain probability. Variables:

RP = (N / T) * 100

Variables:

- RP is the rain probability (%)
- N is the number of forecast models predicting rain
- T is the total number of forecast models used

To calculate the rain probability, divide the number of forecast models predicting rain by the total number of forecast models used. Multiply the result by 100 to convert the fraction to a percentage. This will give the probability that rain will occur at any given point within the forecast area.

## What is a Rain Probability?

Rain probability, also known as the chance of rain, is a measure used in weather forecasting to describe the likelihood of precipitation. It is usually expressed as a percentage, indicating the probability that a specific location will receive at least some amount of precipitation (rain, snow, etc.) in a given period. For example, a 50% rain probability means there is a 50% chance that rain will occur at any given point within the forecast area.

## How to Calculate Rain Probability?

The following steps outline how to calculate the Rain Probability (RP) using the given formula:

- First, determine the number of forecast models predicting rain (N).
- Next, determine the total number of forecast models used (T).
- Next, use the formula RP = (N / T) * 100 to calculate the Rain Probability.
- Finally, calculate the Rain Probability by inserting the values of N and T into the formula.
- After calculating the result, check your answer with the calculator above.

**Example Problem:**

Use the following variables as an example problem to test your knowledge:

Number of forecast models predicting rain (N) = 5

Total number of forecast models used (T) = 10