Satellites can monitor tropical storms and predict surges in strength to warn when a storm is about to become a hurricane, U.S. researchers say.

Scientists at the University of Illinois say one of the biggest problems facing hurricane forecasters is identifying rapid intensification, when storms suddenly transform into much stronger cyclones or hurricanes.

While there have been recent advances in forecasting technology to track the potential path of tropical storms and hurricanes, meteorologists have had little success in predicting rapid intensification, a university release said Wednesday.

UI researchers scoured data from microwave satellites from 1987 to 2008 to see how hurricanes behaved in the 24 hours before they underwent rapid intensification and found that storm systems consistently formed a symmetrical ring of thunderstorms around the center of the system about 6 hours before intensification began.

As the system strengthened into a hurricane, the thunderstorms deepened and the ring became even more well-defined, they said.

"Now we have an observational tool that uses existing data that can set off a red flag for forecasters, so that when they see this convective ring feature, there's a high probability that a storm may undergo rapid intensification," atmospheric sciences Professor Stephen Nesbitt said.

"This is really the first way that we can do this in real time rather than guessing with models or statistical predictions."

Since microwave satellites orbit every 3 to 6 hours, meteorologists can use them to track tropical storms and watch for the telltale rings to give forecasters about a 30-hour warning before a storm hits its maximum strength, the researchers said.