How to Calculate the Weather Forecast Using Naive Forecasting

Naive forecasting predicts no change in the weather.

Most TV weather programs make forecasts using Numerical Weather Prediction, which uses computers to generate probable scenarios based on variables such as temperature, pressure and wind. A much simpler, and often equally accurate method for forecasting the weather is naive forecasting, also known as persistence forecasting. Naive forecasts assume that the weather conditions at the time of the forecast will not change --- if it's 80 degrees and sunny today, it will be 80 degrees and sunny at the same time in the same place tomorrow.

Difficulty:

Moderately Easy

Instructions

1. Take notes on the weather conditions periodically every hour, including but not limited to temperature, humidity, wind, precipitation and air pressure. The more data you collect, the more accurately you can forecast later weather conditions.

2. Calculate data. At the end of the day, calculate the high and low temperature, inches and duration of rainfall, and wind patterns.

3. Forecast the weather for tomorrow and later days with the same measurements of high and low temperature, rainfall and wind that you have observed. This prediction is based on the assumption that there is very little change in weather from day to day in normal climate patterns. The safest forecast is therefore that the weather tomorrow will be the same as it was today.

Tips & Warnings

• The naive forecast is a useful predictor of weather in regions and during seasons with stable weather patterns. In areas where the weather varies significantly from day to day, a naive forecast has a lower probability of being correct.

References

• Weather World 2010: Persistence Method
• What's Up with That?: Forecasting Guru Announces "No Scientific Basis for Forecasting Climate"