Florida Prescribed Fire Had Unexpected Drop In RH

According to TampaBay.com, the prescribed fire in Florida that escaped and may have added smoke to existing fog, contributing to Wednesday’s 50+ vehicle pileup, experienced an unexpected 30% drop in relative humidity. A spokesman said the minimum RH was forecasted to be 60%, but it dropped to 30% in the morning an hour after they started the Rx burn.

 

“A weather forecast from the forestry staff showed that the humidity would not drop below 60 percent all day, a crucial factor in determining whether to proceed with a burn. If humidity dropped to 30 percent or below, the Division of Forestry would have denied the permit.

A form that Burger filled out to document the controlled burn showed that the humidity measured 63 percent at 10 a.m. on Tuesday, so he and a crew of five other employees started the burn at 10:15 a.m. They expected to be finished by noon.

“They do a lot of prescribed burning, and they do a good job at it,” said Department of Agriculture spokesman Terry McElroy. “But something apparently went awry.”

To the crew’s dismay, within an hour after they started the fire, the humidity abruptly dropped to 30 percent, Morse said. That wasn’t part of the forecast, he said.”

 

Interstate 4 Pileup; Dozer Burned

There are conflicting reports about the role smoke from a prescribed fire may have played in the massive vehicle crashes on Interstate 4 in Florida yesterday. Some law enforcement officials are saying that smoke and fog combined to cause low visibility. Others are saying smoke was not a problem, that it was only dense fog. Describing the current activities on the fire, the Division of Forestry said:

“Smoke is going to continue to be our number one concern until this is over.”

The prescribed fire was conducted by the Florida Fish and Wildlife Conservation Commission who started it at 9 a.m. on Tuesday in an area called the Green Swamp. Within three hours it was out of control. Now it is 500 acres and 90% contained.

The Leger has more information about the escaped prescribed fire:

“As the flames picked up, Division of Forestry firefighter John Wurster arrived to help Fish and Wildlife workers. The workers were equipped with a bulldozer that was cutting a fireline in an attempt to stop the flames from spreading.

Conditions suddenly worsened. The wind changed, humidity dropped, and flames increased, Wurster said.

Ten minutes later, Wurster’s fellow firefighter had been burned on his hand and face, the Division of Forestry had lost a $150,000 bulldozer, and firefighters were running from flames.

By late evening, nine Division of Forestry workers helped contain 90 percent of the fire. Smoke continued to billow from the swamp into the morning.”

More Information About the 50-car Pile Up

The death toll has now risen to four. It’s probably going to be long time before the investigation reports (and the civil suits) are complete. Smoke from the escaped prescribed fire may or may not have contributed to the visibility problem. It seems clear that there was some smoke, and some fog, but in what combinations? Here is what the Orlando Sentinel is saying this afternoon:

“But news of a possible problem had been brewing since the night before.

The Division of Forestry notified the FHP at 7:03 p.m. Tuesday night of potential smoke problems from the controlled burn, as part of a formalized interagency agreement. FHP said they would monitor I-4 and close it if needed. FHP also notified the state Department of Transportation, which put out signs with flashing lights that warned of the smoke.

The National Weather Service in Melbourne this morning issued a special weather report warning commuters that visibility in the Polk County area would be down to zero because of smoke from brush fires and fog.

Throughout the day, officials disagreed about the role the smoke and fog played in the crash.

FHP Sgt. Jorge Delahoz said the smoke from the fire may have had some impact, but at the time of the crash it was the fog that reduced visibility in the area. He said people were probably driving at 50 or 70 miles per hour or faster.

A forestry official said he would not say conclusively what caused the pileup until his investigators issued a final report, possibly in the coming week. But the official cautioned that his team could be on scene of the burn for weeks, even months.”

Smoke From Escaped Rx Fire and/or Fog Contribute to 3 Deaths & 50-Car Pileup


According to reports, smoke from an escaped prescribed fire combined with fog contributed to a 50-car pileup and three deaths on Interstate 4 in Florida between Orlando and Tampa. ABC Action News reported yesterday, January 8:

“POLK COUNTY– Crews are working to put out an oversized brush fire in Polk County.

Officials with the Division of Forestry say they issued a 50 acre prescribed burn today in the area of Old Grade Road and I-4.

They believe the wind may have led the fire to grow by an extra 200 acres.

They say no homes are being threatened at this time.

There are concerns that if the fire burns overnight, drivers may face smoky conditions by Wednesday morning.”

Then today ABC Action News further reports in a story about the incident:

“A mixture of fog and smoke from a controlled burn near Old Grade Road created extremely hazardous conditions early this morning.

The burn was supposed to cover only 50 acres, but got out of hand late yesterday and grew to more than 300 acres.

More information from MyFox Tampa Bay:

“POLK CITY – Smoke and fog are causing a surreal scene in Polk County that’s forced the closure of a stretch of Interstate 4, and contributed to a massive pile-up.

All lanes of I-4 are closed between the Polk Parkway and U.S. 27. That’s roughly from Polk City to the Osceola County line.

The lingering smoke combined with the morning fog has brought visibility down to near zero, and deputies say at least 50 vehicles are involved in the massive wreck, and 20 of those are semi-trucks. Several vehicles caught fire, though most of the blazes seemed to be out by 8:30 a.m., judging by the diminishing amount of black smoke rising from the scene.

At least three people are dead, and several more motorists are trapped and waiting for emergency crews.

Those who are unhurt are being asked to stay in their cars for their own safely and the safety of rescue workers.

Yesterday’s brush fire began as a controlled burn, but it jumped a firebreak and eventually grew to 250 acres before being contained.”


According to TheLedger.com a Division of Forestry dozer was burned in the fire yesterday.