(Note-Originally posted 11/29/07, but with fog in the forecast, it bears repeating)
This morning was very foggy across much of the area. I live in a community where many people take a morning constitutional on a regular basis. (By that I mean walk) On the way home from work very early Thursday, I was surprised by a man, who I’ll call Buddy for now, although I might have been tempted to call him something else this morning.
Well, “Buddy” was walking in the street instead of on the sidewalk, and I didn’t see him until I was about 200 feet away. I managed to stop in plenty of time, but it reminded me of a website that explains stopping distances when you are driving your vehicle. I’ll include it here.
December weather is almost nearly perfect in Southwest Florida, but the dry season is often always our fog season. Over the past few years we’ve had some very bad accidents that were due almost completely to fog; the most significant was a multi-car pile-up on Alligator Alley about 5 years ago.
Some interesting facts to keep in mind. When you are traveling 60 mph, you are traveling a mile a minute. That’s 5280 feet a minute, or 88 feet per second. (Those stats are on the above website)
In weather reports we usually mention visibility reports in miles; because that was the official reporting weather stations give us. If visibility is 1/8 of a mile, it means you can see 660 feet, approximately 2 football fields. I will tell you this, on I-75 this morning, my visibility was definitely less than 2 footballs fields in places, even probably less than 1.
For sake of argument, let’s say I could see one football field, or 300 feet. If I had to stop my car to avoid something in front of me, at 60 mph, my stopping distance would be 251 feet, if my reflexes were quick. Logic would then tell you to slow down if you can’t see more than a football field in front of you.
But what about the guy behind you? If you are going slower, will he be able to see you? This was the scenario in Charlotte County a few years ago, when a truck was rear ended by another causing a big fire, and shutting down a part of the Interstate for almost a day.
A good reason to avoid the Interstate if possible on a very foggy morning.