Paul Gross answers common questions about hurricanes
Meteorologist: There's so much to know about these complex storms
DETROIT – Our new weather data system here at Local 4 allows us to show you weather phenomena such as hurricanes like never before, and that has prompted a number of questions, which I'm happy to answer for you!
Do hurricanes form only over the ocean?
Yes, hurricanes only form over the ocean, and not just any ol' ocean water: the surface temperature of that water has to be at least 82 degrees. These warm ocean waters serve as the storm's initial fuel source, so once the hurricane moves off the water and over land, it's intensity quickly begins to diminish.
Why do some hurricanes develop into intense monsters, while others remain weaker?
As mentioned above, one of the ingredients for hurricane formation and development is warm ocean temperatures. Another important factor is wind aloft. Strong wind aloft is very detrimental to a hurricane's development, and we meteorologists watch that upper level wind field very closely. I've seen weak hurricanes suddenly strengthen as they moved over warmer waters and into an area of weaker wind aloft, and very well-developed strong hurricanes weaken quickly after moving into hostile conditions. The next time you see a satellite image of a hurricane, take a look at the solid area of very bright-looking clouds that surround the eye (we meteorologists call that the Central Dense Overcast, or CDO). If the CDO is nearly circular and centered right around the eye, then there is very little upper level wind shear and the hurricane is doing well. However, if the CDO is not symmetrical and looks "pushed" to one side relative to the eye, then the hurricane is experiencing wind shear and is in a more hostile environment.
What is it like to be in the eye of a hurricane?
I've never been in the eye of a hurricane, but I know people who have. Amazingly, the eye of a hurricane is calm and pleasant. In fact, the sun can be out! However, to get into the eye of the storm, you first must get through the most intense storms and strongest wind, all of which ring the eye. Generations ago when we knew much less about hurricanes, people in the eye of the storm thought that the storm was over, and started heading outside only to have the wind come roaring back from the opposite direction after the eye passed by.
I heard you guys mention something about tornadoes in hurricanes. What's that all about?
Hurricanes create an environment very favorable for tornadoes. The thunderstorms ahead of and to the right of the hurricane's path are especially prone to generate tornadoes, so the Storm Prediction Center almost always issues a tornado watch for many hours for those in the favored areas. It's bad enough to experience a hurricane, but imagine getting a tornado during the hurricane. Now THAT would be a bad day.
Since hurricanes are so destructive, why can't we just drop a bomb into them and disrupt their circulations so they weaken?
Don't laugh...I get this question every year. Hurricanes are so massive and release so much energy that there is no bomb on Earth that could do that. Remember that massive amounts of water vapor evaporate off those warm ocean temperatures and is incorporated into the storm. When water vapor condenses into rain drops, energy is released. Now think about all of that intense rain associated with a hurricane: that's a LOT of energy, and no bomb is strong enough to overcome that.
Has a hurricane ever hit Detroit?
As I mentioned above, hurricanes weaken once they hit land, so no hurricane has ever hit Detroit. HOWEVER, the rainstorms associated with former Hurricane Ike and a former Pacific Ocean tropical storm crossed our area on back-to-back days in September 2008 and dropped 3-to-6 inches of rain. Going back even further is the amazing event of September 25th, 1941, when a hurricane that hit the Texas coast raced 1000 miles in only twenty-four hours, interacted with a cold front, and actually generated 75 mph wind gusts (that's officially hurricane force wind) in downtown Detroit. It wasn't a hurricane that hit us that day, but it once was!
Feel free to email me if you have any other questions!
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