# Tornados spawned by hurricanes? **URL:** \ **Category:** Factual Questions\ **Created:** [August 28, 2005, 2:12pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972 "2005-08-28T14:12:50Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![TommyTutone](https://avatars.discourse-cdn.com/v4/letter/t/c4cdca/32.png) [@TommyTutone](https://boards.straightdope.com/u/TommyTutone)\ **Post date:** [August 28, 2005, 2:12pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/1 "2005-08-28T14:12:50Z")
I love my wife very much. She is reasonably well educated and very successful in her job, but once in awhile, she gets an insane notion in her head and I need to prove her otherwise. Today’s case in point is that she told me that a lot of damage done by hurricanes are not by the hurricanes themselves, but by the tornados that form on the fringe edges of said hurricanes. In an attempt to keep harmony in the home, I said nothing, but she could tell by the look on my face I thought her mad since tornados are generally created on land (although waterspouts are the rare exception) through wind conditions that have nothing to do with hurricanes which are created over water. Can someone set the straight dope for us so that one of us can be committed once and for all? ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [August 28, 2005, 2:19pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/2 "2005-08-28T14:19:45Z")
I hope you have a nice asylum picked out for yourself, **Tommy**. > [@](#): > > Some frequently asked questions about tornadoes spawned by hurricanes and tropical storms. > > Q: What percentage of hurricanes and tropical storms spawn tornadoes? > > A: Almost all such storms making landfall in the United States spawn at least one tornado, provided enough of the storm’s circulation moves over land. This means that Gulf Coast landfalling storms are more likely to produce tornadoes than Atlantic Coast hurricanes that “sideswipe” the coastline. > > Q: What parts of a hurricane or tropical storm are most favored for tornado formation? > > A: The right-front quadrant (relative to the hurricane’s motion) is strongly favored for tornadoes. Most of the tornadoes form in outer rain bands about 50 to 200 miles from the storm’s center, but some have been documented to occur in the inner core or even in the eyewall. Considering the predicted path of Hurricane Charley on Saturday, this would make the eastern part of North Carolina most vulnerable to tornadoes. > > Q: How long after landfall are tropical storm tornadoes a threat? > > A: A tropical storm may spawn tornadoes from a day or two prior to landfall to up to three days after landfall. Statistics show that most of the tornadoes occur on the day of landfall or the next day. > > The most likely time for tropical storm tornadoes is during daylight hours, although they can occur during the night, too. > > Although statistically the largest number of tropical tornadoes occur on the day of a storm’s landfall, some of the biggest and most damaging outbreaks have taken place one or two days after landfall, as with Beulah in 1967, Danny in 1985 and Beryl in 1994. > > Q: Why are tropical tornadoes especially difficult to deal with? > > A: Tropical tornadoes often are spawned by unusually small storm cells that may not appear particularly dangerous on weather radars, especially if the cells are more than about 60 miles from the radar. > > In addition, these small storms often tend to produce little or no lightning or thunder and might not look very threatening visually to the average person. > > Furthermore, the tornadoes often are obscured by rain, and the storm cells spawning them might move rapidly, leaving little time to take evasive action once the threat has been perceived. > > THE ATLANTIC OCEANOGRAPHIC AND METEOROLOGICAL LABORATORY IN MIAMI. [http://www.newsobserver.com/news/story/1527584p-7702761c.html](http://www.newsobserver.com/news/story/1527584p-7702761c.html) ---
**Author:** ![Scruloose](https://avatars.discourse-cdn.com/v4/letter/s/e68b1a/32.png) [@Scruloose](https://boards.straightdope.com/u/Scruloose)\ **Post date:** [August 28, 2005, 2:26pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/3 "2005-08-28T14:26:34Z")
Also, waterspouts aren’t all that uncommon. I’ve seen plenty of them - even one on Lake Michigan. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [August 28, 2005, 2:31pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/4 "2005-08-28T14:31:59Z")
> [@Scruloose](#): > > Also, waterspouts aren’t all that uncommon. I’ve seen plenty of them - even one on Lake Michigan. Me too, regarding the Lake Michigan thing. Now that was exciting, since we were sitting on the deck outside our house, and watching the thing form about 100 yards from us. ---
**Author:** ![Viscera](https://avatars.discourse-cdn.com/v4/letter/v/258eb7/32.png) [@Viscera](https://boards.straightdope.com/u/Viscera)\ **Post date:** [August 28, 2005, 5:37pm UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/5 "2005-08-28T17:37:32Z")
Most hurricanes produce tornadoes, but are they the main source of wind damage? No way. Most hurricanes produce maybe a handful of tornadoes, but even in those that are prolific tornado producers (say maybe 100+), there is no way that the land area affected by tornadoes is anywhere near the order of magnitude of the land area affected by the hurricane. Furthermore, tropical tornadoes are typically weak (F0 and F1s), and do not last much longer than a couple minutes. This would be from tornadoes on the day or so of landfall. The outbreaks mentioned above occuring a day or two after landfall occur when the amount of wind shear is still relatively high, but with added surface heating (more breaks between rain bands) the next day or two, those tornadoes are more closely related to their Plains cousins, and can be stronger. But bottom line, tornadoes are not the main cause of damage. I’d argue that tornado damage is well below 1% of the overall damage on most storms (no cites, but I could probably find some if needed), when you consider storm surge, inland flooding (arguably the biggest damage producer), and strong winds near the coast. ---
**Author:** ![Rysdad](https://avatars.discourse-cdn.com/v4/letter/r/7cd45c/32.png) [@Rysdad](https://boards.straightdope.com/u/Rysdad)\ **Post date:** [August 29, 2005, 12:48am UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/6 "2005-08-29T00:48:34Z")
Right now, the Hurricane Katrina is a Cat 5 with with winds over 156 as listed on the following Saffir-Simpson Scale: [http://en.wikipedia.org/wiki/Saffir-Simpson\_Hurricane\_Scale](http://en.wikipedia.org/wiki/Saffir-Simpson_Hurricane_Scale) (The Beaufort Scale is listed on the same page.) It will, in all liklihood, spawn numerous tornados, the speeds of which are rated on the Fujita scale: [http://en.wikipedia.org/wiki/Fujita\_scale](http://en.wikipedia.org/wiki/Fujita_scale) I don’t suppose it makes much difference that a Cat 5 hurricane only has a wind speed rating of an F2 tornado when you consider that Katrina’s hurricane winds themselves span an area _over 200 miles wide_. You know a storm is serious when tornados are only a _symptom_. ---
**Author:** ![casdave](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@casdave](https://boards.straightdope.com/u/casdave)\ **Post date:** [August 29, 2005, 6:58am UTC](https://boards.straightdope.com/t/tornados-spawned-by-hurricanes/318972/7 "2005-08-29T06:58:29Z")
I saw some programme about tornados, where they interviewed Dr Fujita (AKA Dr Tornado) During hurricane Andrew not only were tornados spawned, but also they adapted a pattern where five or six of them were rotating around a central point, sort of a tornado of tornados. The pattern of detstruction was also characteristic of tornados, even given that you might have thought that the hurricane would mask it, things such as small areas suffering intense destruction(and certain types of impact damage) whilst areas adjacent underwent relatively mild damage. In terms of wind blown damage, these tornados were very much more destructive than even the peak winds of Andrew, and over far wider areas that you would want to know.