By Paul Homewood
A bit of perspective from Accuweather, with the help of SPC’s Greg Carbin and Harold Brooks of NSSL.
In the wake of the deadly Midwest tornado outbreak on Sunday, many people are wondering how rare tornadoes are during November.
The short answer is that tornadoes can occur in the Midwest during any month of the year. However, the number of tornadoes diminishes substantially during the cold-weather months.
There is a secondary severe weather season that occurs during October and November, which favors the Deep South.
While rare, tornadoes reaching as far north as the Midwest and mid-Atlantic are not unheard of during November. Occasionally, a small number of the tornadoes can be rather strong.
According to Harold Brooks, senior research scientist at the National Severe Storms Laboratory in Norman, Okla., “The peak of the secondary season for the United States as a whole is rather diffuse, but is centered over the middle of November.”
The uptick in severe thunderstorms during October and November can be simply explained by the routine strengthening of storm systems during the autumn that are able to pull lingering warm and humid air northward from the Gulf of Mexico.
Brooks stated that this particular event had very strong winds aloft, which not only greatly increased the forward speed of the severe weather, but also added fuel to the individual storms.
According to Greg Carbin, warning coordination meteorologist with the National Weather Service’s Storm Prediction Center, “Winds aloft over the region strengthened rapidly from 70 mph to 140 mph on Sunday.”
A chain of events happened at just the right time over a concentrated area. Winds near the surface rapidly brought in moisture. During the midday Sunday, the sun came out and warmed the air near the ground as the strong winds aloft brought in dry, cooler air. The result was an extremely unstable atmosphere and a significant number of strong tornadoes.
Every decade as far back as the 1980s has brought multiple tornado outbreaks during November with a number of fatalities.
“During November there is a tornado outbreak about once every seven to eight years,” Carbin stated.
“The most comparable event is probably Nov. 22, 1992, which had a large number of tornadoes in Indiana and Kentucky,” Brooks said.
According to the Indianapolis National Weather Service office, the 1992 outbreak produced the largest number of November tornadoes [15] on a single day in Indiana on record.
Other significant November outbreaks have occurred during the last 12 years. The last decade brought eight tornado outbreaks. The most significant of these for the Midwest occurred in 2001 and 2002.
During the Veterans Day Outbreak of Nov. 9 to 11, 2002, there were close to 80 tornadoes that took the lives of 36 people and injured more than 300 others.
In 2001, spanning Nov. 23 to 24, there were approximately five dozen tornadoes that killed 13 people and injured more than 200 others.
November tornadoes were very rare during the 1960s and 1970s.
The preliminary count of tornadoes through Nov. 17, 2013 is 886, which is well below the most recent eight-year annual average of 1,424 through mid-November.
As bad as the event was on Sunday, it could have been worse.
“If the storm system would have tracked over the lower Mississippi Valley, closer to the source of warm and humid air, instead of the Great Lakes, we would have likely had an even greater number of severe thunderstorms and tornadoes,” Carbin said.
Moving forward through the end of the month, there will likely be a few more potent storm systems developing. However, the chance that all of the necessary ingredients will come together to produce a tornado outbreak for each and every system is quite low.
For people in the Midwest, the secondary tornado season is winding down through the latter half of November.
Odds are against a similar setup as far north as the last over the Midwest. However, as climatology suggests, the chances are higher for severe thunderstorms over the South.
http://www.accuweather.com/en/weather-news/how-rare-was-midwest-tornado-outbreak/20074227
We have had two in Sydney this year. Prior to this year I can’t recall any in my lifetime although in the early 1990’s there was a peculiar storm that had revolving winds like a horizontal tornado that caused some damage on the North Shore of Sydney
So, in other words, we should not consider a November tornado out break at all unusual or unprecedented. In fact, it appears to be the 2nd most active time for tornadoes in the US.
Looking at the map, I grew up just above the numeral 7. I know tornadoes the way some people know snowfall. I apologize for describing a tornado system as ordinary when others are yelling that the system is Armageddon Plus. At the next appropriate opportunity, I will tell again about the time(s) Tupelo was blown away.
I meant to ask this the other day, before the November storms struck. What would happen to a skyscraper if it tangled with an F4 or even an F5 tornado? Or would say, the St Louis Arch survive an F5 tornado? So far, it seems to me that tornadoes are attracted to mobile homes (trailer parks) and avoid skyscrapers. I asked several meteorologists this years ago but never received an answer. (I think it was posed to the Weather Channel). Have there been any “high” buildings knocked down by a tornado?
I don’t recall collapses, but there was a tornado through downtown Fort Worth abouta decade ago.
Downtown Ft Worth, the Tandy Center Building (among a number of others) tangled with a Tornado on March 28, 2000. It was designated an F2 at the time.
Article and pictures:
http://www.fortwortharchitecture.com/tornado.htm
Damage Survey and Assessment of Fort Worth Tornado, 28 March 2000 (pdf file)
http://www.depts.ttu.edu/nwi/Pubs/reports/D3-28-00%20Tor%20FtWorth.pdf
Video of the aftermath downtown:
.
“However, the number of tornadoes diminishes substantially during the cold-weather months.”
It looks also like its a bit quieter during the hottest months.
It appears that the “changing seasons” are when the tornados are most prevalent. Which makes sense, because they seem to be are driven by north-south differences.
J. Philip Peterson says November 19, 2013 at 6:50 pm
I meant to ask this the other day, before the November storms struck. What would happen to a skyscraper if it tangled with an F4 or even an F5 tornado?
The main structure of these buildings is usually engineered to withstand far greater wind loads, than they are ever likely to have to sustain…..that’s what engineering is all about. Margins of safety.
Pretty hard to make the skin withstand that sort of treatment though.. as Jim’s video shows.
What is so special about Va. and W. Va.?
Seriously, as a lifetime resident of one of the states that gets the most fall tornadoes per square mile than Texas, I find it no surprise to see fall twisters. Another fall in the boot.
sadly, it is also no surprise to find the shysters and hucksters milking the climate change turnip.
Arkansas, Louisiana, Alabama, and Mississippi together have an area roughly equal to that of Texas. Yet, they total 24 to the 9 of Texas.. I will also add that most of the fall twisters in Texas occur in the eastern third of the state.
Peterson: “What would happen to a skyscraper if it tangled with an F4 or even an F5 tornado?”
__Jim gave one example, only other I know of is this one.
http://en.wikipedia.org/wiki/1970_Lubbock_tornado
This was the subject of a Weatherbell.com post on SATURDAY, the day before this outbreak. I also tweeted the second season idea several times last week , even before that post. It is a well known phenom, as explained here. However the average climatic ambulance chaser does not know that ( among almost everything they shoot their mouths off about) and so jump on things like this with glee. A true example of ignorance leading to bliss, so they can push their point, even as it causes misery to people. A heartless bunch, to say the least
Gee, Joe, why don’t you tell us what you really think? Please, don’t hold back! Heh. Yeah, the fools show their ignorance every time they yell about “global warming causes _______ (fill in the blank).
Brent Walker. The Australian Bureau of Meteorology has this page on tornadoes in NSW, stating there have been 364 tornadoes recorded across NSW from 1795 to June 2003, although most don’t exceed F2 in strength http://www.bom.gov.au/nsw/sevwx/tornadofact.shtml . Out of the 6 listed from 1998 to 2002, 3 are in November. Doesn’t seem that uncommon here, or at this time of year.
tteclod, was that March 28, 2000 by any chance?
Great article. I go to school at Illinois State University, about 30 minutes from Washington, IL. I woke up at 11:30 (it was a Sunday) to some light rain and then 10 minutes later it was the strongest storm I’ve ever seen. We couldn’t see ANYTHING out any of the windows due to the swirling rain and the window panes looked like they were about to give so we ran into the stairwell. Trees were uprooted and thrown across the street, and roofs of some apartments blew off across the street, leaving the residents and their belongings completely exposed to the storm. My roommates and I found baseball-sized hail after the storm as well.
I know this pales in comparison with an area like Washington, IL but just goes to show that it’s not just the tornado stricken areas who get hit hard. Thoughts and prayers for those affected.
I have a good friend who was a lawyer working in that building in Fort Worth the day it got hit. He was on the 20th floor, I believe, and he said they stood at their windows watching the storm develop and move closer – and suddenly they all realized that the black center of the storm was headed straight for them, and was going to be there in about 5 minutes. (Nobody believed it would really go downtown until the last minute) No time to get out of the building, so they all raced for the internal, enclosed stairwell, where they linked arms with each other, and with the metal stair railing. The lights went out, and he said waiting there in the darkness with the sounds of glass smashing and metal ripping all around them was almost impossible to describe – he said it was too overwhelming to even be scared, all you could do was hang on and hope that somehow you would still be alive when it was over.
They all were, amazingly – afaik, no fatalities in that building, although most of the exterior skin was stripped off. He also told me that one of the (almost) funny parts in the days following was that, at the time, this building housed many legal offices. (in the reconstruction, it was converted to high-end condos) The effect of the tornado was to suck every file, and every piece of paper out of the building and up into the tornado. For a week afterwards, you could see all kinds of college students and anyone else who wanted a quick job going up and down the Trinity River bottom (where the tornado finally petered out) scooping up loads of paper to try and sell them back to all of the lawyers who were desperately trying to put their client’s files back together. (the world hadn’t gone paperless yet!)
A building that didn’t do so well was Waco, 1953 – a 6 story brick building got hit and collapsed in downtown Waco, killing 30 people in that one building alone – 114 people killed overall by that tornado, 597 injured, still one of the worst alltime.
Ah yes, Tandy… where all our daily reports when I worked at Radio Shack as a teen were sent.
The take-home message from that video is… in a tornado, stay away from the windows! If they get broken or sucked right out, you’d find yourself standing hundreds of feet off the ground.
2008, Atlanta, Westin Peachtree Plaza Hotel, 73 stories, hit by an F-2 (130 mph winds). Blew out about 500 windows.
Interesting story: the SEC conference basketball championship was being played a few blocks away in the Georgia Dome. A desperation 3-point basket was made at the final buzzer, sending the game into overtime. There was no tornado warning. It hit the dome during the overtime, damaging the building, but injuring no one. Had the game not gone into overtime, thousands would have been outside walking to their cars. Many would have been walking back to the Westin, and be in the path of thousands of shards of glass raining down. Amazingly, there was but one fatality from the storm.
It sounds as if there is some really cold weather headed for the Midwest and even Deep South by the weekend.
http://www.accuweather.com/en/weather-news/arctic-cold-blast-takes-aim-at/20110789
“January like temperatures” are forecast, up to 20 degrees below normal.
http://www.accuweather.com/en/weather-news/freezing-temperatures-to-arriv/20117012
Apparently the UK has most tornadoes relative to land area!
http://www.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html
But that’s probably because we have an army of bowler hatted civil servants to go round counting them!
To those who think this outbreak was not unusual. Look at this news story: http://usnews.nbcnews.com/_news/2013/11/19/21530485-damage-from-worst-in-a-century-midwest-storm-system-could-cost-1-billion?lite
Strongest tornado EVER recorded in Illinois in the month of November with winds estimated at 190 mph ( a high end EF4 and there were at least 2 EF4s that day). Isn’t it just plain luck they didn’t strike the center of a larger town? If the Weather Channel is to be believed (not always the case), you have to go back over 100 years to find a tornado outbreak this big this far north in November. And yes, since it happened back then it certainly can’t be blamed on CAGW today.
I believe all but one of the tornadoes occurred in the high or moderate risk outlook areas issued by SPC. That is an excellent forecast. It turns out there were actually 4 touchdowns in Michigan with 2 fatalities. There have only been 6 tornadoes previously recorded in Michigan in November since 1950.
I am absolutely NOT a fan of all the hype you see about severe weather in the media these days but nearly everyone who was affected by this severe weather outbreak credits the great forecasts for saving lives.
So no, you should not consider a tornado outbreak in November in the United States unusual, and this one certainly isn’t as bad as some of the outbreaks in southern states, BUT this was very unusual for the number and strength of the tornadoes so far north in mid November.
cjames
We have just passed the centenary of the “White Hurricane of November 1913”, described as
one of the deadliest maritime weather disasters in North American history.”
which hit the Great Lakes.
Nicknamed the “White Hurricane” and the ‘Freshwater Fury” the 1913 storm remains the most devastating natural disaster to ever strike the Great Lakes.
http://www.regions.noaa.gov/great-lakes/centennial_anniversary_storm_of_1913/
The same ingredients were there:
November, being the prime month for such monsters to start materializing, has had more than its share of super storms.
As Polar outbreaks become more regular and intense, surging south
into the area, they meet up with the warmer, moisture laden air from the Gulf of Mexico. Add to this a roaring jet stream with lots of energy and you have the ingredients for dynamic storm development.
While this occurs with some regularity during fall and winter months in the Great Lakes, there are probably a dozen or so
mammoth storms which are noted in history for their severity, creating extensive losses in life and property, particularly to
the shipping industry.
http://www.crh.noaa.gov/dtx/stm_1913.php
Most storm systems, fortunately, don’t spawn tornadoes, but some do. At the end of the day it’s pot luck.
Huntsville, Alabama, where I once worked, had one of its most deadly tornado events on Nov 15, 1989. It was an F4 that killed 21 people. Alabama for sure has a second tornado season in the fall.
http://en.wikipedia.org/wiki/November_1989_tornado_outbreak
The Nov outbreaks occur where the Jet Stream kinks. The path of the Jet Stream is determined by the blocking high over the Atlantic Ocean and where it develops. Latitude north or south does not matter. I’ll repeat; how far north a tornado outbreak occurs in November does not matter in the slightest. It is just a chaos signal in a chaotic system. THAT they occur in November is a sign of the encroaching cold systems beginning to swing south for winter, just like in the spring the cold systems are still swinging south for a limited time before the Jet Stream moves north for the summer.
To Eric Eikenberry.
“how far north a tornado outbreak occurs in November does not matter in the slightest”. Wow! I think you just flunked Meteorology 101. I wonder how many tornadoes have occurred north of the Canadian Border in November?
Eric – yes, cold air must be present in order for severe systems that spawn tornados to develop. That’s why peak season is April/May and then in Oct/Nov arctic air masses are reasserting themselves against lingering warm fall air masses. In the summer there is less of a contrast in general compared to those times. Therefore, for the AGW idiots to try and make something out of this as a result of climate change they then have to acknowledge the presence of the cold air that is 50% responsible for these clashes.
Paul Homewood says:
“Apparently the UK has most tornadoes relative to land area!
http://www.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html
But that’s probably because we have an army of bowler hatted civil servants to go round counting them!”
And a tornado is a wind that can actually blow that bowler hat off their head..
No measurement needed. 🙂
re: Paul Homewood
Anyone with an interest in Great Lakes shipwrecks and storms should check out: ,i>Great Lakes Shipwrecks and Survivals by William Ratigan (at Amazon.com) or, if you can find it in an old book bookstore, Walter Havighurst’s The Long Ships Passing
Is it just me, or are there others in this world that feel thankful that God, or Mother Nature, or whatever you choose to label severe weather seems to almost never choose heavily populated areas to set a toronado down. I may be speaking out of turn, but it seems like grace for humans as a whole, but hell for a an unfortunate few. I know there have been instances of populous areas that have been hit by twisters, but usually it is a small town or towns. Why???
Shawn, I would say probably that throughout history, small towns and villages that didn’t get flattened by a tornado stood a much better chance of growing into big cities than ones that did tend to get hit. People take residence in places where they feel safer. So big cities naturally grow up in places that are less hazardous.
This is all very interesting, I can add the Nov 11, 1911 tornado outbreak and blizzards.
http://www.crh.noaa.gov/lmk/?n=nov_11_1911_cold_front
http://www.crh.noaa.gov/eax/?n=nov_11_1911
This was a bit over 5 months after the large eruption of Taal volcano. There was a lot of volcanic activity around this time. Novarupta in 1912, the biggest bang of the 20th century, probably made 1913 worse.
If the solar cycles of the future remain small like this one, resembles cycle 14. If volcanic activity increases to early 1900’s level, then these strong cold fronts should happen again. That would be a test of AGW, I suppose.