Alabama has seen fewer tornadoes thus far in 2010 than in the past 16 years — certainly good news for Alabamians but no reason to go unprepared, says the National Weather Service.

From Jan. 1 through Sept. 20 of this year, the state has seen 18 tornadoes. That’s the lowest number recorded up to this point since 1993. Eleven of those struck Central Alabama, with one occurring in the Clanton area on March 25.

The cause? Chiefly, according to meteorologists, the swift transition from a colder-than-normal winter to a hotter-than-normal summer. These more extreme conditions caused the “battle zone” between cold and warm air to shift farther south in the winter and farther north in the summer.

But, as always, Alabama weather is unpredictable. Experts remind residents that Alabama has a secondary severe weather season that peaks in November and early December.

“Things could change. We could have a very active fall season,” said NWS meteorologist Jim Westland. “A light season in the spring does not have any predictive value for what could happen in the fall.”

Westland went on to add that Alabama would be “very lucky” to not have any more tornadoes in 2010. In fact, there have been several years when there were more tornadoes in the fall than during spring months.

As for reaching a record low, tornadoes throughout history are difficult to measure. Only since the early ’90s, with the arrival of Doppler radar, has there been relatively reliable equipment for locating tornadoes. For this reason, statistics from the 1980s tend to be much lower.

“Tornadoes are kind of tricky because we’ve gotten better at tracking them and reporting them more and more,” Westland explained. “It’s difficult to say if this is actually a record low or not.”

The most important message to remember, Westland indicated, is to always stay prepared for severe weather.

“Our phrase is, ‘Don’t let your guard down.’ It could change in a hurry,” he said.