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yeah, it's heading over in this direction over the next three days with lots of rain...
which we need... lots of fores fires the last month or so in Florida
Unfortunately, storms are a major cause of forest fires from the lightning.
Any one have a dive report from Venice as to the conditions the storm is kicking up? I'm thinking of going out first thing in the morning if it's not too bad...I'll post on the vis after I get back.
the danger of very dry conditions over weeks can be offset by the passing
of the storm.
the temporary danger of lightning as the storm passes is infinitesimal by comparison
but don't believe me, listen to what the officials in charge of fighting fires
in the east coast of Florida are saying (they're happy):
The prospect of a wet storm without hurricane-force wind was welcomed by firefighters who have been battling wildfires for six weeks on Florida's east coast.
"A good soaking rain would do a lot to help stop the fires in our area," said Pat Kuehn, a spokeswoman for Volusia County Fire Services. "It has been a hard fire season. We've had several fires a week here."
You'd be singing a different tune if it was aimed at your side of the state! Spent the better part of the day tying down things in the yard and putting extra lines on the boat.
the danger of very dry conditions over weeks can be offset by the passing
of the storm.
the temporary danger of lightning as the storm passes is infinitesimal by comparison
but don't believe me, listen to what the officials in charge of fighting fires
in the east coast of Florida are saying (they're happy):
The prospect of a wet storm without hurricane-force wind was welcomed by firefighters who have been battling wildfires for six weeks on Florida's east coast.
"A good soaking rain would do a lot to help stop the fires in our area," said Pat Kuehn, a spokeswoman for Volusia County Fire Services. "It has been a hard fire season. We've had several fires a week here."
That was my argument also, but a paramedic friend pointed out that most fires that started during non stormy times were generally caused by people, either intentionally or otherwise and were noticed quickly and occured near population centers with fire fighting infrastructure. Conversly, fires started by lightning generally occur far from established routes of approach, burn over a wider front and by the time they threaten structures, have already destroyed thousands of acres of forest.
Remember the fires of 1998? It was an exceptionally wet season, but there were so many fires started by lightning that firefighters from all over the U.S. had to be brought in to help fight them. I remember it so well because I was working for Disney, and when the fires were finally brought under control, all the theme parks were comping admissions to the firefighters and their families out of gratitude.
The statistics go both ways, though. This is from the Colorado Division of Emergency Management:Lightning strikes are the single greatest cause of forest fires. Between 1991 and 2000, 59 percent of the wildfires in the United States were caused by lightning strikes and 41 percent were caused by humans. Colorado averages about 2,500 wildfires each year. Already this year Colorado has lost nearly 10,000 acres in more than 280 fires. This is more than three times greater than our 2000 fire season and much earlier in the year.
And then this from a FEMA website:Wildfire is one of the most destructive natural forces on the planet. While sometimes caused by lightning, most wildfires -- nine out of 10 – are caused by people. An average of 106,000 wildfires break out each year in the U.S. These fires consume an average of 4 million acres! But in 2000, 7.5 million acres burned in the U.S. That is an area about the size of Massachusetts, Rhode Island and Delaware combined!
59% vs. 41% and 10% vs. 90%...Well, you know that quote attributed to Sam Clemens..."There are lies, there are damn lies, and then there are statistics"
Anyway, I found an interesting article on cnn.com about self perpetuating lightning caused by fires:
'Dry lightning' sparks Western wildfires
August 21, 2000
Web posted at: 11:07 p.m. EDT (0307 GMT)
ATLANTA (CNN) -- Tinder dry fields and forests in Western states have provided the fuel for dozens of large wildfires. And lightning has provided the spark to ignite the flames in some cases, which can set off a vicious circle in an exceptionally dry year such as this one.
Fires sparked by lightning generate their own weather, spawning more lightning, which can start even more fires.
Here's how it works:
• A big fire sends heat and smoke as high as six miles up into the sky.
• The heat encounters cooler air, producing a cloud.
• The cloud generates little localized rain, as well as plenty of what is called "dry lightning."
"In other words, it may be raining here, and the bolt would shoot out five miles (eight kilometers) from where the rain is and hit the ground where there is no rain. And we see a lot of that this year in the West," said Fire Team Section Chief Ray Johnston.
A bolt of lightning is about as wide as a human finger.
Negatively charged lightning, the most common kind of lightning in thunderstorms, lasts about 41 microseconds or 41-millionths of a second.
But almost every positively charged lightning bolt, the kind most often associated with "dry lightning, lasts up to a full half a second longer -- zapping the ground with a 30,000 degree burst of what scientists call "continuing current."
"So the positives are more effective at starting fires," said Don Latham of the United States Department of Agriculture's Fire Sciences Laboratory. "Not because they're positive, necessarily, but rather because they have a continuing current, which not all negatives do."
By studying pictures from space shuttles, scientists have learned that lightning can occur up to 50 times a minute in a big storm.
Officials began mapping fires and "hot spots" in the 1960s. Currently the USDA Forest Service at the National Interagency Fire Center uses three aircraft: a Sabreliner 80 Jet, a Super King Air 200 and a King Air B-90.
With infrared cameras aboard these huge flying laboratories, it is possible to scan 1 million acres per hour and detect an eight- to 12-inch "hot spot" from 10,000 feet above the ground. The information helps create computer animations that enable firefighters to plot the likely course of fires caused by lightning.
But with a record number of acres going up in wildfires so far this year, scientists still don't have a way to break nature's vicious cycle of fires started by lightning, generating more lightning, which starts more fires.
right now, with or without lightning, Florida is burning. it needs lots of rain. the
tropical storm will bring much needed rain. firefighters happy.
while the storm passes, it may or may not cause lighning fires. it will pass by
quickly anyway, so the threat of lighting fires is minimal. firefighters unconcerned.
the storm will leave in its wake a soaked FLorida, which will help with the on-going
fires. firefighters happy.
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We now have Tropical Storm Alberto!
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Originally Posted by cudachaser
