Scientists continue to advance the process of updating the National Oceanic and Atmospheric Administration's (NOAA) Space Weather Scales, with the next steps expected to be taken as early as this year.

Just like there's a classification system for hurricanes and tornadoes, space weather storms that develop and pose threats to Earth have their own classification system. But these storms are a little more complex than terrestrial weather, and they must be categorized into three different types of events: geomagnetic storms, solar radiation storms and radio blackouts. These three primary areas of focus highlight the types of impacts a solar flare can have on our environment, with the scales also providing information on the likelihood of a certain level occurring and the intensity of each category, which is rated on a scale of 1 to 5.

The scales were designed in 1999 as space weather started becoming a more popular area of research. But with historic events, including the Halloween solar storm in October 2003 and the Gannon event in May 2024, bringing new information to light, leaders at NOAA and the Space Weather Prediction Center (SWPC) determined that the information in the scales had become outdated and confusing for the public.

"This is space weather, and it's something that's challenging to many people. When you start talking about geomagnetic storms, X-rays, protons and energetic particles, people just don't really understand it," Bill Murtagh, program coordinator for the SWPC, told Space.com in an interview here at the American Meteorological Society's (AMS) annual meeting. "We have to find a balance to what's presented in the scales that benefits our primary customers, which are the operators of critical infrastructure — such as power grids, satellites and the airlines — but also for the general public."

In 2024, the SWPC collaborated with the National Weather Service and the IDA Science and Technology Policy Institute (STPI) to ask members of the public and the different types of stakeholders that rely on space weather conditions and forecast data to provide feedback on the current scales. Nearly 500 people from almost 200 different engagements domestically and internationally participated, and the findings were shared at the AMS' annual meeting in January.