According to the rumours, an auction of the business is at an early stage and a deal might not go through. Should there be one, private equity is most likely the buyer in a deal that could be valued at more than $1 billion, the people said.

IBM agreed to buy the business in 2015, purchasing The Weather Company's business-to-business, mobile and cloud-based businesses, including Weather.com, which provides weather forecasts around the globe. The deal price was thought to be more than $2 billion.

The Weather Channel agreed to license weather-forecast data and analytics from IBM. At the time, IBM wanted to use its cloud infrastructure to provide accurate weather forecasts and help companies control costs. The business issues more than 25 billion forecasts a day, according to the company's website.

A sale of the weather unit would be a part of a broader push by IBM to streamline its operations as the once-dominant company's shares languish near levels they traded at more than 20 years ago.