The test will take place at 10 a.m. Wednesday, February 20 and sirens will sound for about three minutes.
If there's a severe weather watch or warning in effect at the time of the scheduled test, then the sound tests will not be conducted.
Other than these previously announced tests, all sirens should be considered to be an actual tornado warning.
Hall County's Warning System is tested silently every morning at 9 a.m.
http://accesswdun.com/article/2013/2/258433