Weather Radar Failed as Charley Approached

As Hurricane Charley bore down on Florida this month, the principal radar covering the landfall area went down due to mechanical failure — and wasn't restored until 14 hours before the storm smashed into the state, according to documents and officials.

While backup radars still would have tracked the hurricane as it made landfall in the Punta Gorda (search) area Aug. 13, they might not have detected any local tornadoes generated by the storm system, government and private weather experts said.

Residents of Tampa Bay know they had a close call, because the storm was thought to be headed their way. The Associated Press learned of the close call with the radar outage when the news service obtained an internal "Bi-Monthly Activity Report" of the National Weather Service (search).

"We performed yeoman service and got that radar up," said John McNulty, director of the NWS Office of Operational Systems. "There was no loss of life attributable to the radar being down."

Twenty-six U.S. deaths have been attributed to the storm, which suddenly made a sharp right turn into Florida's west coast, about 70 miles south of the originally projected bull's-eye.

"The Radar Operations Center Hotline, along with ROC contract support services staff, provided extensive assistance to the Tampa Bay WFO (Weather Forecast Office) on the evening of 12 August and into the early morning hours of 13 August to restore the radar to operation in advance of Hurricane Charley (search)," the report said.

"The site had radar, transition power source and backup generator problems" and parts had to be flown in immediately, the report said. Weather Service officials said a contractor for the parts manufacturer also was dispatched to Tampa to oversee the repairs.

Floyd Hauth, a former Air Force meteorologist and now a private consultant to the federal government, said the memo demonstrates "time was very critical."

"They would have been in serious trouble without use of the radar. You couldn't track tornadoes," said Hauth, of Osceola Mills, Pa.

McNulty, the top Weather Service official for keeping the equipment operational, said in an interview the problems in Tampa began Aug. 10 during a routine test of the radar's backup power system.

A switch that was supposed to start the backup generator failed. This caused a transition power source (TPS) system — designed to operate for 13 seconds to prevent power surges — to remain on to power the radar. The TPS then failed, going to a safe mode to preserve its battery.

Those problems made the radar inoperable until Aug. 11, two days before the storm made landfall.

On Aug. 12, when it became clear the west coast of Florida was at great risk, another part failed — this time on the radar itself. The equipment, called a signal processor power supply, generates the signal from the radar. Without it, the system is useless.

With the storm getting closer, a frantic effort was under way to repair the system. At 4 p.m., replacement parts were ordered. At 9 p.m. McNulty was called at home and told of the problem. He, in turn, called National Weather Service Director David Johnson, a retired Air Force brigadier general.

The problem was fixed at 2:30 a.m., about 14 hours before Charley hit land. Weather Service officials, not taking any chances, had the radar operating on the backup diesel generator as soon as the part was installed.

Steven Cooper, the deputy regional director of the Weather Service's southern region, said radar sites at Melbourne, Miami and Key West also provide coverage for the west-central part of Florida where the hurricane hit.

"We feel very comfortable because our offices have such backup," he said, adding that overlapping radars work especially well because of the short distances between central Florida's east and west coasts.

Cooper agreed, however, that while the features of a hurricane are easy to detect on all the radars, the closest radar to a storm has the best fine resolution to pick up local tornadoes.

"The tornadoes you get are very small scale and very difficult to detect," Cooper said. "The farther away you are, it's harder to detect very small features."

Cooper said most tornadoes generated by a hurricane system are relatively weak and the damage paths generally are small. They are not the killer tornadoes that most people fear.