Weather Imagery

Even though the Earth does pass closer to the sun during part of its orbit, this is not what’s responsible for our hot summers or cold winter months. If this were the case, then the northern and southern hemispheres would both have their summers and winters at the same time. However as you’ll see below, exactly the opposite is true. When it’s summer in the northern hemisphere, it’s winter in the southern hemisphere.

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Lightning is one of those things that captures everyone’s attention because there’s just the right mix of fear and curiosity which draws everyone to the show. To go along with lightning’s beauty, there are a lot of interesting facts some people might not have known. Here’s a list of some interesting facts about lightning:

Lightning Odds

• The odds of getting struck by lightning in the U.S. in any single year is 1 in 700,000.
• The odds of being struck in your lifetime is 1 in 5,000.

Lightning Science

• A single lightning bolt is about 50,000°F or 5 times hotter than the surface of the sun.
• A lightning bolt is anywhere from 1,000,000 to 1,000,000,000 volts and between 10,000 and 200,000 amps. Or about 215 kWh (kilowatt hours).
• There are two types of lightning; negative strikes and positive strikes. Positive strikes are 5 times more powerful than negative strikes and positive charge flows instead of negative charge.
• The average lightning bolt could light a 100 watt light bulb for about 3 months.
• The average lightning bolt is 6 miles long, although Cape Canaveral Kennedy Space Center has indicated some as long as 75 miles.
• The thickness of a lightning bolt is about the size of a silver dollar. It only looks bigger because it is so bright.
• A lightning bolt is made of a series of strokes from about 3 to 20, with an average of about four. The duration of each lightning bolt can vary, but typically average about 30 microseconds.

Lightning Statistics

• In this order Florida, Texas and North Carolina are the top 3 states for lightning induced deaths.
• Florida has the highest lightning strike density of anywhere in the U.S. (about 12 strikes for every square mile per year).
• In this order Florida, Michigan and Pennsylvania are the top 3 states for lightning injuries.
• About 20% of those unfortunate enough to be struck by lightning die. From 1959 to 2003 a total of 3,696 people have been killed by lightning.
• Around the world there are about 8 million lightning strikes each day.
• Each year, an average 22 million cloud to ground lightning flashes hit the United States and surrounding coastal waters.
• An estimated 307,000 lightning insurance claims are filed each year in the United States. That’s about 1 claim for every 57 Cloud to Ground lightning strikes. It is also estimated lightning causes about $400,000,000 in damages each year in the United States.
• There are about 10,000 forest fires started by lightning each year.
• Lightning kills more people that tornadoes and hurricanes combined. It is the single most dangerous thing produced by a thunderstorm.
• Approximately 494,000 cloud to ground lightning strikes occur in Colorado each year. Colorado ranks 26th in the nation.

Lightning Oddities

• Many survivors of lightning strikes report that right before being struck by lightning their hair was standing on end and they had a metallic taste in their mouth.
• Lightning causes objects to explode because it instantly turns any water to steam. This includes concrete, trees, asphalt and clothes. It’s been known to blow the clothes off people due to the sweat/water instantly vaporizing creating a steam explosion.
• About 1% of all lightning deaths in the U.S. are a result of people talking on a corded phone during a thunderstorm.
• The U.S. Agricultural Department estimates 80% of accidental livestock deaths are a result of lightning strikes.
• Park ranger Roy Sullivan was struck by lightning seven times between 1942 and 1977
• The irrational fear of lightning is known as keraunophobia. The fear of thunder is termed brontophobia.

The last time a commercial plane crashed in the United States due to a lightning strike was about 40 years ago. On December 8, 1962 lighting hit a Pan American Boeing 707 in a holding pattern over Elkton, Md. The lightning created a spark that ignited jet fuel vapor in a holding tank, triggering an explosion that killed all 81 aboard. Ironically, the FAA estimates that each commercial airliner will be hit by lightning once a year (some will get hit more than once, some won’t get hit at all). And in some cases, the airplane itself actually triggers the lightning! So why doesn’t lightning cause commercial airliners to crash? There are three main reasons: highly conductive outer shell, surge/shielding/grounding protectors on electronic equipment, and jet fuel which produces much less explosive vapor.

The first line of defense is the outer skin of a commercial jet which is made of aluminum or a composite with interwoven conductive fibers which provides a path for the electric current. When lightning strikes the skin of an airplane, it travels along the outside of the aircraft and discharges back into the air. Passengers on board might not even know the aircraft was struck unless they happen to see the flash or hear the thunder through the roar of the engines. Pilots may notice a short flickering of lights or jumps in their instrumentation, but it should never cause a failure. We can thank NASA for this.

NASA conducted several tests in the 1980′s in which pilots deliberately flew an F106B jet into thunderstorms to gather data and see what affects lightning would have on the aircraft. Despite being struck over 700 times on 1400 missions the aircraft never sustained any damage. However, it was concluded based on the data collected that on board instrumentation could be affected by small electrical charges caused by the lightning.

Even though the electric current remained on the outer skin of the aircraft, small electrical transients could be induced on wiring inside the aircraft. As a result, regulations were put in place such that all electronic equipment, fuel tanks and fuel lines have their own built-in surge protection, shielding and special grounding systems. Even if the system experiences flickering, it will return to normal in less than a second.

As a last line of defense, jet fuel (Jet-A) now has additives that reduce the amount of vapor produced. Although the vapors are still explosive, the fuel tanks are insulated and grounded which makes it very difficult (dare I say impossible?) for an electrical ignition source to enter the tanks and ignite the fuel.

As a strange side note, if pilots avoid the large thunderstorms, why are aircraft still being struck by lightning? Well, that’s because smaller clouds can also produce lightning and the airplane itself may actually trigger it.

Other Lightning Myths

• Is Ball Lightning Real?
• Do Lightning Rods Attract Lightning?
• Can Lightning Be Used As a Source of Power?
• Can Lightning Strike the Same Place Twice?
• Do Car Tires Protect Me From Lightning?
• Can Lightning Strike Me Inside My House?

Wind chill is a measure of how cold people and animals feel based on heat loss due to wind. In cold and windy weather conditions, the skin loses heat through evaporation much more quickly than if the wind were not blowing. Therefore, it feels much cooler when it’s cold outside and the wind is blowing. The faster the wind blows, the greater the chilling affect. This is called wind chill, “real feel”, or apparent temperature.

There are a couple misconceptions about wind chill. The first is humidity does not noticeably affect a wind chill reading. In fact, in the newest formula used by the National Weather Service, the humidity reading was left out. The second myth is inanimate objects such as metal, wood and plastics experience wind chill just like we humans do. This isn’t true. The only affect a cold wind has on these objects is that they cool off faster than had there been no wind, but they will not cool below the actual outside temperature. So as an example, if it’s -5°F outside with a -25°F wind chill, the metal on your car will only cool to -5°F. It will not get any colder no matter how fast the wind blows.

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Ball lightning is as mysterious as Big Foot and as controversial as UFO’s. No scientist has ever been able to conclusively prove its existence while at the same time no scientist has been able to prove it doesn’t exist either. All we have are a lot of sketches and eyewitness accounts which hold no weight in the scientific community, or with me. Especially when the event only lasts a few seconds, the whiteness was not prepared for what they were about to see and the subject is usually startled at the perceived event. So where does that leave us? Is ball lightning real or is it just a myth?

That may be a difficult question to answer because we have absolutely no scientific evidence to prove it exists. We do have a lot of theories that claim it could exist, but none have been able to recreate the elusive phenomenon in a scientifically controlled environment. As I said before, there are lots of sketches and eyewitness testimony, but that doesn’t hold any weight in the scientific community. So what do people think ball lightning is? Is it really lightning? Is it some subterranean energy that is created by enormous stresses in rocks? Is it a super heated plasma? Is it an after image or a sort of optical illusion? Yes. It is all of these things and more.

Some mistake welding slag, Saint Elmo’s Fire, arcing electricity and rapid oxidation as ball lightning. It’s tough for me to say what ball lightning isn’t when I don’t know what it is. But, if these things are ball lighting then they have been witnessed for years and it wouldn’t be that phenomenal to observe such an event. That being said, those who claim to have seen ball lighting describe it as having some extraordinary capabilities. It hovers or floats slowly in mid air and either rapidly disappears or sometimes explodes with a loud bang. Some even claim it has passed through solid objects only to reappear on the other side. This hardly sounds like a case of mistaken identity. However, if ball lightning does exist it could very well redefine some of the fundamental properties of electricity and magnetism.

However, until I read a scientific paper on the production of ball lightning which has been verified by other independent scientists, I will continue to hold a sort of agnostic opinion on the subject. You could chose to believe it exists, but it would be a leap of faith as I think you will have a hard time (if not impossible) finding scientific evidence to support your belief.

Other Lightning Myths

• Can Lightning Crash an Airplane?
• Do Lightning Rods Attract Lightning?
• Can Lightning Be Used As a Source of Power?
• Can Lightning Strike the Same Place Twice?
• Do Car Tires Protect Me From Lightning?
• Can Lightning Strike Me Inside My House?