Jefferson and Grant counties are getting a $2.3 million upgrade to their warning siren systems that sound for tornadoes. They also sound if there is an emergency at the Pine Bluff Arsenal. The improvements are being paid for by the Federal Emergency Management Agency. The new system is being installed in Grant County. Jefferson County`s equipment upgrades will begin later this month. When the sirens are used, the public hears specific tones which signify the type of warning being issued. ------ The tones are: --Whoop tone -- denotes a chemical accident or incident. --Beep tone -- signals to a chemical accident exercise. --Steady tone -- warns of a tornado. --High-Low tone -- hazardous material spill or accident. --Chime tone -- all-clear notice or test of the warning system.