Skiers and snowboarders searching for snow have a number of free tools available to them via the internet. The trick is learning enough about each piece of data to know when it can help you find snow and when to ignore it. This article will talk about the infrared satellite image and how you can use it to find snow.
Infrared satellite images detect clouds based on temperatures. In this image, blue areas show colder clouds, which means they are higher in the sky. Red colors show warmer areas, which often means the satellite is sensing the warmer ground with no clouds overhead. Credit: OnTheSnow
Satellite weather data comes from a piece of equipment that sits about 22,500 miles above the earth. Most of these satellites are stationary above a particular point on earth, so they always show the same view of the earth, 24 hours a day, 365 days a year.
Each satellite has numerous sensors that view the earth in slightly different ways. The infrared sensor peers down at the earth and measures the temperature of the clouds above the ground, or if there are no clouds, then it shows the temperature of the ground itself. Since the atmosphere (usually) becomes colder further up into the sky, clouds that are higher in the sky are colder. On the satellite image, these colder clouds show up as different colors than lower, warmer clouds or even the ground itself.