By Renata Geraldo,

Seattle weather was in the sunny 70s in mid-July when weather forecasters saw the heat wave that has driven 90-degree highs last week was on its way.

That’s a change from decades past, when heat could hit or miss by surprise. Advances in technology and technique have turned weather into a booming piece of the tech sector with satellites, radars and developments in artificial intelligence.

Forecasters today can tell what the weather will be with more accuracy and longer lead times thanks to a much improved system of weather satellites and increasingly complex algorithms. The opportunity for artificial intelligence-driven advances and the growing intensity in catastrophic weather events due to climate change have drawn more innovators and entrepreneurs into weather forecasting, claiming they have access to more information than ever before.

The heat wave that hit the Pacific Northwest was predicted early through data from the satellites that measure the atmosphere over parts of the Pacific Ocean, said University of Washington state climatologist Nick Bond. The satellites gathered data on humidity, temperature and wind, and computers analyzed those conditions through complex equations that predicted that the heat would soon hit the region.

“It’s really pretty remarkable what we can do in that way, from satellites that are way above the air looking down,” Bond said.

The models are not easy to build. According to journalist Andrew Blum in his book “The Weather Machine,” “Landing a spacecraft on Mars requires dealing with hundreds of mathematical variables. Making a global atmospheric model requires hundreds of thousands.”

Bond said weather-prediction technology was able to accurately forecast the 2021 Pacific Northwest heat wave that lasted from the end of June to the beginning of July. The heat wave resulted in at least 100 heat-related deaths, according to the Washington State Department of Health.

Forecasting has always had a level of uncertainty. For example, it is difficult to predict rain because it can be spotty and hit different parts of the geographical grid forecasters analyze to tell the weather. And as extreme events such as thunderstorms and tornadoes become more intense because of climate change, forecasting becomes even more challenging, Bond said.