If you hear sirens this morning, it's only a test.

At 10 a.m., Hall County's 911/Central Communications Center will conduct its quarterly test of the tornado sirens located around the county.

The sirens, which can be heard from about a mile away, are meant to alert people that a tornado has been spotted.

"It will last approximately three minutes," said Hall County Public Safety Director Marty Nix. "They're not meant for indoor warning systems. They're meant for people who are outside."

Nix said the siren system is tested silently every Wednesday.

"We just make sure it sends a signal back to us," Nix said. "We get a confirmation of that here at the 911 center."

But he said the county makes sure everything is working properly by giving the sirens a dress rehearsal once every three months.

"The reason that we do these audible tests is that even though we can do quiet tests, we do it about once a quarter so we can have people at these sites and ensure they're working properly and document anything that goes wrong," Nix said.

There are 14 tornado sirens stationed at various sites around the county, from the Hall County Fire Station in Clermont to Spout Springs Elementary School in
Flowery Branch.

"They came about shortly after the tornadoes in 1998," Nix said. "Hall County received a grant for these sirens, and we implemented them throughout the county."

In 1998, a powerful tornado ripped through North Hall. It left 12 people dead, around 100 families without homes and caused some $15 million in losses, including damage to two schools in its path.

Gainesville has a history of deadly tornadoes. In 1903, a twister hit the New Holland area and killed more than 100. In 1936, a tornado struck the downtown square, leveling buildings and trapping victims beneath them, killing 203.

In August of 2008, three tornadoes hit South Hall.
One of the tornadoes struck the roof of Lyman Hall Elementary School on Memorial Park Drive while about 65 children were still in the school attending an after-school program.

There were no injuries reported in the storms, but 107 properties across the county received about $3.36 million in damages.

Nix said the tornado sirens are sounded any time the National Weather Service issues a tornado warning or there is a confirmed sighting of a funnel cloud by law enforcement personnel.

During the 2008 storms, the county was able to sound the tornado sirens ahead of an alert from the weather service.

"An Oakwood police officer spotted the tornado and notified the 911 center," Nix said.