New radar will have St. Mary covered

A private company is installing a Doppler radar atop the Parish Courthouse in Franklin, with the potential to give emergency officials important tornado and hurricane information they can’t get now.

The installation will provide coverage to St. Mary, which is effectively out of range for some radar applications by the closest National Weather Service Doppler radars in Lake Charles and Hammond.

And, said Homeland Security Director Jimmy Broussard, “you can repeat that there will be no cost to St. Mary Parish government.”

The radar dome was hoisted atop the courthouse Saturday. The radar is being installed by Climavision, a private company based in Louisville, Kentucky. Climavision’s website says the company is expanding the number of Doppler radars outside the metro areas where National Weather Service and TV weather stations tend to be.

“We think it would help as far as predicting the strength of wind, rain and water,” Broussard said.

Doppler radar works on the same principle that makes a train sound higher in pitch as it approaches and lower in pitch as it moves away. The microwave beams emitted by radars act the same way.

The radar measures the shift in frequencies to determine speed and distance.

Those beams travel only in line of sight. So areas like St. Mary that are far from radars may be covered high above land while radar targets close to the ground are shielded by the earth’s curvature.

Additional radars help by “plugging the gap,” Broussard said.

Having coverage close to the ground can be especially effective in locations where conditions are favorable for tornadoes, for example.

“A ‘hook echo’ describes a pattern in radar reflectivity images that looks like a hook extending from the radar echo, usually in the right-rear part of the storm (relative to the motion of the storm),” according to the National Severe Storm Laboratory website.

“A hook is often associated with a mesocyclone and indicates favorable conditions for tornado formation.”

The radar on the courthouse will not be operated by or affiliated with the National Weather Service.

But “in general, yeah, the more radars we have access to, the better,” said Chief Meteorologist Roger Erickson at the NWS in Lake Charles.

The radar on top of the St. Mary Courthouse could be in operation by the end of July, Broussard said.