Police say the 46-year-old last had contact with a family member on June 17 around 7:23 p.m.
Police say Lyde has made concerning statements regarding his life and may be in possession of a firearm.
JBPD says he was last seen at the Hampton Inn, located at 1515 1st Street North. He is driving a 2018 gray Dodge Journey with South Carolina Tag RDY983, police say.
Lyde is described by police as six feet and one inch tall, roughly 210 pounds and has a faded unknown type tattoo on his upper shoulder.
If you see him, please contact the Jacksonville Beach Police Department at 904-270-1661.