Prior to 1950 meteorologists knew so little about tornadoes that they were sometimes forbidden from using the term in forecasts. They figured it would've caused needless panic more than actually saving lives. But things have changed. Today, people often know a few days in advance that severe weather is possible, and they almost always have enough warning to take shelter when a tornado strikes. Paying attention to these warnings is a crucial part of tornado survival.
To put modern forecasting in perspective, let's take a look at how far it's come. The first documented, accurate tornado forecast happened in central Oklahoma on March 25, 1948. It was essentially based on the simple observation that weather patterns were similar to those that produced a tornado several days before. But it took a while to see improvements; warnings in the 1950s and '60s often came just seconds before a twister hit [source: Galvin]. By the 1980s, however, radar technology allowed meteorologists to see conditions inside the storms, increasing warning time to five minutes. Additional radar advances in 1993 nearly doubled that lead time, and today warnings can give people 15 minutes or more to prepare [source: Howard]. That may not sound like very long, but it certainly gives you a lot more options than a few seconds would!
Of course, forecasting still isn't perfect, and sometimes meteorologists can be wrong. But choosing to ignore warnings just because they aren't always right is asking for trouble. When it comes to tornado forecasts, don't take them for granted — take shelter!