Almost everything else has changed, though, and all for the good. Airborne weather radar is much better than it used to be. Color radar systems have a fourth color, magenta, to better define areas of heavy rainfall. The radar systems are digital for a better picture and include other enhancements. Airborne Doppler weather radar is now available in some aircraft.
Radar is often shown on a multifunction display so the relationship of any weather activity to the planned route is shown clearly. So is the relationship of weather to the destination airport. Stormscope information can also be shown on a multifunction display.
Ground weather radar information is better, too. Nexrad has replaced the weather radar system that was in place twenty years ago, and it offers a far better picture of precipitation. Information from this radar system is now available to air traffic controllers.
Many FBOs have a WSI radar display, which is a national (or regional) composite of all the radar sites. Before takeoff, pilots can look at a weather radar picture and go flying with at least a knowledge of what it looked like before takeoff and how it was moving. Real-time weather information is available on the internet.
Air traffic control takes a much more aggressive role in routing airplanes around thunderstorms today, especially in areas where air traffic is congested. When a regional airline pilot was asked how he dealt with thunderstorms and he said,"It's easy, ATC won't let us fly routes that are affected by thunderstorms!"
Thunderstorm accidents are far fewer now than twenty years ago, and the process and technology behind this improved situtation is explained clearly in this fascinating book.