November 17, 2013 Tornadoes --- A Fall Outbreak For The Ages

[Hoosier]

I've spent quite a bit of time digging into the numbers and quite honestly, what happened last weekend is pretty unbelievable.

 

First off, here's where things stand right now.  Remember that these numbers are preliminary and may change.

 

EF0:  13

EF1:  29

EF2:  23

EF3:  7

EF4:  2

Total:  74

 

The main purpose of this thread is to focus on this subforum as that's where almost all of the tornadoes occurred.  In fact, 71 out of 74 tornadoes occurred from Missouri-Kentucky northward (3 EF0/EF1 occurred in TN).  The November 10, 2002 tornado outbreak gets brought up quite a bit since it was a significant outbreak, but from a regional perspective, this outbreak has demolished that one.

 

 

 

If we broaden out for a moment, we see that the preliminary total from 11/17/2013 has surpassed the total from 11/10/2002, and that outbreak had a much broader geographic reach.

 

 

 

If we're really generous and include the tornadoes that occurred late on the 9th and into the early 10th (which technically shouldn't be part of the outbreak as many hours went by until the next tornado), the total does surpass what occurred last weekend, but again, over a much bigger area.

 

 

 

Back to focusing on this subforum.  I'm going to take some time to focus on the two states that bore the brunt of this outbreak, Illinois and Indiana.

 

The preliminary total of 24 tornadoes in Illinois would tie for 5th place.  Here are the most active tornado days on record in Illinois:

 

4/19/1996:  39
4/2/2006:  36
4/7/1998:  26
8/10/1974:  25
5/10/2003:  24
11/17/2013:  24

 

I wanted to broaden things out beyond November outbreaks so I looked at other fall months.  Here are the single day September/October/November tornado records (or what were the November records) for Illinois:

 

9/26/1959:  12 … F2 or greater:  9/26/1959:  6
10/24/2001 and 10/26/2010:  5 … F2 or greater: 10/10/1969 and 10/18/2004:  2  
11/12/1965:  6 … F2 or greater:  11/12/1965:  5

 

Those November numbers are not typos.  The previous high for tornadoes in a single day was 6 while the previous high for F2 or greater tornadoes was 5.  The preliminary numbers for 11/17 are 24 tornadoes with 14 of them EF2+.  Pretty astonishing.

 

 

Doing the same thing for Indiana, starting with most active tornado days on record...

 

6/2/1990:  37

4/19/2011:  29

11/17/2013:  28

5/30/2004:  24

5/25/2011:  22

 

(4 out of the top 5 days are from the past 10 years...better detection anyone?)

 

 

Now, here are the single day September/October/November tornado records (or what were the November records) for Indiana:

 

9/20/2002:  6 … F2 or greater:  9/20/2002:  4
10/26/2010:  13 … F2 or greater:  10/24/1967:  6
11/22/1992:  15 … F2 or greater:  11/22/1992:  10

 

The current preliminary numbers for 11/17 (28 tornadoes/13 EF2+) beat the numbers from the 1992 outbreak.

 

 

Here's a bunch of factoids regarding this outbreak:

 

-11/17 is the first November tornado outbreak to produce multiple violent tornadoes in the region let alone the same state

 

-There had never been an F/EF4 tornado in Illinois in November from 1950-2012 and there were 2 on 11/17.   Grazulis indicates no F4s in Illinois going back to 1880.

 

-There had only been 20 F/EF2 or greater tornadoes in Illinois in November from 1950-2012 and there were 14 on 11/17.

-There had only been 27 F/EF2 or greater tornadoes in Indiana in November from 1950-2012 and there were 13 on 11/17.

 

 

Finally, to get a sense of how significant this outbreak was, I wanted to look at other notable tornado days in the subforum.  I define this subforum to be approximately the area in red:

 

 

 

 

Using Tornado History Project, I was able to put together a list of days that had the most F/EF2 or greater tornadoes in the subforum.  Per the map above, this includes all of Wisconsin, Michigan, Illinois, Indiana, Ohio, Kentucky, and small parts of Minnesota, Iowa and Missouri. 

 

Here are the days with the most F/EF2 or greater tornadoes:

 

4/3/1974:  58
11/17/2013:  32
4/11/1965:  31
6/2/1990:  29
12/18/1957:  22
4/21/1967:  19
4/3/1956:  16
5/18/1995:  16
10/18/2007:  16
4/19-20/1996:  15 (includes IN/KY tornadoes after midnight)

 

 

There's all kinds of caveats with rating/assessing damage and one of them is that some long track tornadoes from the past may have really been multiple tornadoes.  That being said, that is some pretty fine company.  FWIW, the previous single day November record for the subforum was 11 (11/22/1992).

 

In summary, this was a very impressive event and I believe it's the new benchmark for Fall severe weather outbreaks, especially for the Lakes/Ohio Valley Region on the whole. 
 

[andyhb]

Good compilation Hoosier, this will definitely be one to remember (and compare future Fall outbreaks to, not only in the GL/OV, but also countrywide).

 

Someone correct me if I'm wrong, but I believe this is now the biggest single day tornado outbreak in terms of number of tornadoes on record in the Fall in the US.

[The_Doctor]

It shows how far we've come in terms of advanced warning when you look at the fatality count for this event. Still not perfect, but much better than even 15 or 20 years ago.

[Stebo]

It shows how far we've come in terms of advanced warning when you look at the fatality count for this event. Still not perfect, but much better than even 15 or 20 years ago.

I am thoroughly convinced that if this event happened any other day of the week that it would have been more deadly, imagine this event happening on a school day for example. Sundays most people are at home vs being out and about or working.

[Hoosier]

Good compilation Hoosier, this will definitely be one to remember (and compare future Fall outbreaks to, not only in the GL/OV, but also countrywide).

 

Someone correct me if I'm wrong, but I believe this is now the biggest single day tornado outbreak in terms of number of tornadoes on record in the Fall in the US.

 

Yes it is.

 

I've been thinking about it and I wonder if this is near the ceiling in terms of what we can get in this region in the Fall.  It's hard to imagine something much more impressive. 

[andyhb]

Yes it is.

 

I've been thinking about it and I wonder if this is near the ceiling in terms of what we can get in this region in the Fall.  It's hard to imagine something much more impressive. 

 

One of the things I can think of is if the temperatures/dewpoints in IN and MI had reached some of the guidance progs <48 hrs out. That rain mass in the morning likely limited some of the moisture return/subsequent heating that areas further north received.

[Hoosier]

One of the things I can think of is if the temperatures/dewpoints in IN and MI had reached some of the guidance progs <48 hrs out. That rain mass in the morning likely limited some of the moisture return/subsequent heating that areas further north received.

 

Good point.  I guess I forgot about that.  Temps never made it past the mid 60s here while much of the guidance was indicating highs AOA 70, yet we still had 5 tornadoes in my county.  Does make you wonder about it would've been like with no airmass contamination. 

 

As significant as this outbreak was, we know we can get something worse.  Events like 3/28/20, 4/11/65, 4/3/74, etc come to mind.  We haven't really seen a Spring outbreak along those lines in quite some time (in this region)

[andyhb]

As significant as this outbreak was, we know we can get something worse.  Events like 3/28/20, 4/11/65, 4/3/74, etc come to mind.  We haven't really seen a Spring outbreak along those lines in quite some time (in this region)

 

As far as GL outbreaks go, Palm Sunday II is the grand daddy of them all, even 4/3/74 and 3/28/20 don't come close to the amount of violent tornadoes that event produced in GL region (4/3/74, despite the Monticello tornado among others, was more focused on the OV and then south into the TN Valley).

[Hoosier]

As far as GL outbreaks go, Palm Sunday II is the grand daddy of them all, even 4/3/74 and 3/28/20 don't come close to the amount of violent tornadoes that event produced in GL region (4/3/74, despite the Monticello tornado among others, was more focused on the OV and then south into the TN Valley).

 

4/11/65 and 4/3/74 are responsible for about a quarter of the F4/F5 tornadoes that have occurred in the subforum.  It's even more drastic when you narrow it down to IN and KY.  Those two dates are responsible for about half of the F4/F5 tornadoes in those states (KY's all coming on 4/3/74). 

[Ensō]

4/11/65 and 4/3/74 are responsible for about a quarter of the F4/F5 tornadoes that have occurred in the subforum.  It's even more drastic when you narrow it down to IN and KY.  Those two dates are responsible for about half of the F4/F5 tornadoes in those states (KY's all coming on 4/3/74). 

 

I think 4/11/65 in the northern half of Indiana is comparable to 4/27/11 in the northern half of Alabama, with extremely violent tornado outbreaks occurring over a relatively small spatial/temporal scale. April 27 obviously produced more extremely long-track tornadoes, and produced tornadoes over a wider area overall, but the events are quite similar in those particular areas.

 

April 27 also skews the tornado statistics for Alabama, though to a much lesser extent than Palm Sunday in Indiana since Alabama is more tornado-prone.

[Hoosier]

I think 4/11/65 in the northern half of Indiana is comparable to 4/27/11 in the northern half of Alabama, with extremely violent tornado outbreaks occurring over a relatively small spatial/temporal scale. April 27 obviously produced more extremely long-track tornadoes, and produced tornadoes over a wider area overall, but the events are quite similar in those particular areas.

 

April 27 also skews the tornado statistics for Alabama, though to a much lesser extent than Palm Sunday in Indiana since Alabama is more tornado-prone.

 

Not sure I agree with the last part.  4/27/11 produced about a quarter of the violent tornadoes on record in Alabama while Palm Sunday is also responsible for about a quarter of the violent tornadoes on record in Indiana.  When you adjust for size (AL is quite a bit bigger than IN...like 1.4 times larger in terms of square miles), everything from total number of tornadoes to significant tornadoes to violent tornadoes from 1950-2012 is pretty similar to Indiana.  Perhaps going back prior to 1950 would reveal something different but I'm not sure. 

[andyhb]

Not sure I agree with the last part.  4/27/11 produced about a quarter of the violent tornadoes on record in Alabama while Palm Sunday is also responsible for about a quarter of the violent tornadoes on record in Indiana.  When you adjust for size (AL is quite a bit bigger than IN...like 1.4 times larger in terms of square miles), everything from total number of tornadoes to significant tornadoes to violent tornadoes from 1950-2012 is pretty similar to Indiana.  Perhaps going back prior to 1950 would reveal something different but I'm not sure. 

 

I believe it would, since events like 3/21/32 and 4/20/20 would elevate AL beyond IN.

[Hoosier]

I believe it would, since events like 3/21/32 and 4/20/20 would elevate AL beyond IN.

 

I'll have to look into those more.  I mean I've heard of them but don't remember how bad they were.   

 

Of course there are so many ways to analyze/compare statistics and trying to do it with a database that has flaws... ehh. 

[Ensō]

Honestly, after doing the math the difference isn't as big as I'd expected. There were nine violent tornadoes on 4/27/11 in Alabama out of 41 total (21.9%), and eight out of 28 (28.6%) in Indiana on 4/11/65. I suppose I probably overestimated the total number of violent tornadoes in Alabama. In any event, the point is that I think they're very comparable events for their respective areas.

 

And yeah, 3/21/32, 4/20/20 and others were extremely intense outbreaks. And the Enigma Outbreak too, for that matter. Alabama is certainly no stranger to violent, widespread outbreaks.

[Hoosier]

Honestly, after doing the math the difference isn't as big as I'd expected. There were nine violent tornadoes on 4/27/11 in Alabama out of 41 total (21.9%), and eight out of 28 (28.6%) in Indiana on 4/11/65. I suppose I probably overestimated the total number of violent tornadoes in Alabama. In any event, the point is that I think they're very comparable events for their respective areas.

 

And yeah, 3/21/32, 4/20/20 and others were extremely intense outbreaks. And the Enigma Outbreak too, for that matter. Alabama is certainly no stranger to violent, widespread outbreaks.

 

My totals are a bit different than those.  I used Tornadohistoryproject which accounts for tornadoes that cross in from other states and I have 11 out of 44 for Alabama and 8 out of 33 for Indiana.

[andyhb]

I'll have to look into those more.  I mean I've heard of them but don't remember how bad they were.   

 

Of course there are so many ways to analyze/compare statistics and trying to do it with a database that has flaws... ehh. 

 

3/21/32 was the deadliest AL outbreak of all time, with at least 268 fatalities in-state. Actually, multiple areas that got hit on 4/27 were struck in that outbreak as well (Cullman and Tuscaloosa metros, for example).

 

4/20/20 was an outbreak with at least 6 violent, long-track tornadoes between MS and AL, which all caused 20 or more fatalities each.

[Hoosier]

3/21/32 was the deadliest AL outbreak of all time, with at least 268 fatalities in-state. Actually, multiple areas that got hit on 4/27 were struck in that outbreak as well (Cullman and Tuscaloosa metros, for example).

 

4/20/20 was an outbreak with at least 6 violent, long-track tornadoes between MS and AL, which all caused 20 or more fatalities each.

 

I won't argue about folks down South being more vulnerable to dying but that gets into various non-meteorological reasons.  One of the differences between Indiana and the states down south is that forest coverage isn't really much of an issue in much of Indiana other than the southern part of the state.

[Ensō]

 

 

3/21/32 was the deadliest AL outbreak of all time, with at least 268 fatalities in-state. Actually, multiple areas that got hit on 4/27 were struck in that outbreak as well (Cullman and Tuscaloosa metros, for example).

 

4/20/20 was an outbreak with at least 6 violent, long-track tornadoes between MS and AL, which all caused 20 or more fatalities each.

 

 

Including an extremely long-track (130 miles) tornado that was likely an F5 and affected virtually the same areas as the Hackleburg and Tanner tornadoes. The '32 outbreak was pretty similar to April 27 in intensity, at least in Alabama, which is obviously saying something.

 

Anyhow, we're getting way off-track. I'd like to add up Thompson's Destruction Potential Index for last Sunday's outbreak when I have time. It isn't a particularly useful metric, but it's interesting nonetheless.

[Gilbertfly]

[Hoosier]

For s&g I pulled out the big green book last night (Significant Tornadoes by Tom Grazulis in case anyone didn't know) and counted the numbers from 1880-1949 for Alabama and Indiana.

 

Alabama:

 

F2+:  362 tornadoes on 173 days

F4+:  29 tornadoes on 18 days

 

Day with most F4+:  3/21/1932 - 8

Day with most F2+:  3/21/1932 - 15

 

 

Indiana:

 

F2+:  185 tornadoes on 115 days

F4+:  32 tornadoes on 22 days

 

Day with most F4+:  5/26/1917 and 3/28/1920 - 4

Day with most F2+:  3/23/1917 and 3/28/1920 - 7

 

 

The most surprising thing to me is that Indiana beats Alabama in total violent tornadoes/days even without adjusting for size differences.  However, Alabama beats Indiana in F2+ tornadoes/days when adjusting for size.  Sorta interesting, probably shouldn't read a ton into this but at least the ratings from this time period should be consistent given that they came from the same person. 

[Ensō]

For s&g I pulled out the big green book last night (Significant Tornadoes by Tom Grazulis in case anyone didn't know) and counted the numbers from 1880-1949 for Alabama and Indiana.

 

Alabama:

 

F2+:  362 tornadoes on 173 days

F4+:  29 tornadoes on 18 days

 

Day with most F4+:  3/21/1932 - 8

Day with most F2+:  3/21/1932 - 15

 

 

Indiana:

 

F2+:  185 tornadoes on 115 days

F4+:  32 tornadoes on 22 days

 

Day with most F4+:  5/26/1917 and 3/28/1920 - 4

Day with most F2+:  3/23/1917 and 3/28/1920 - 7

 

 

The most surprising thing to me is that Indiana beats Alabama in total violent tornadoes/days even without adjusting for size differences.  However, Alabama beats Indiana in F2+ tornadoes/days when adjusting for size.  Sorta interesting, probably shouldn't read a ton into this but at least the ratings from this time period should be consistent given that they came from the same person. 

 

Thanks, I've been meaning to do the same sorta thing but never got around to it. As you said, it's difficult to draw many conclusions given how questionable and error/bias-prone the historical record is, but that's pretty interesting. It seems, at least subjectively, that Indiana and Alabama are among the most active states when it comes to the "super outbreak"-type events, so maybe it shouldn't be that surprising to see Indiana being on par with Alabama.

 

Incidentally, I've been (very slowly) working on some climatology-related stuff for my blog and some of the maps have produced pretty similar results. These aren't final and I haven't thoroughly reviewed the data yet, but it should be close to accurate. All maps are for 1950-2012 and damages are in 2011 USD. Click for larger versions.

 

Tornadoes per 10,000 sq. miles:

 

 

Damage per capita, adjusted by population, income and housing:

 

 

Damage per square mile:

 

 

Damage per tornado:

 

[hm8]

^Nice maps. Don't think I've seen it laid out in a damage per area/tornado/population way before

[RobertSul]

Interesting maps for sure! Massachusetts sticks out like a sore thumb on a couple of them.

[Ensō]

Thanks. Yeah, that'd be almost entirely because of the 1953 Worcester tornado and, to a lesser extent, the 2011 Springfield tornado. Massachusetts is somewhat more tornado-prone than other states in the Northeast though, especially Central Massachusetts.

[Hoosier]

 

Thanks, I've been meaning to do the same sorta thing but never got around to it. As you said, it's difficult to draw many conclusions given how questionable and error/bias-prone the historical record is, but that's pretty interesting. It seems, at least subjectively, that Indiana and Alabama are among the most active states when it comes to the "super outbreak"-type events, so maybe it shouldn't be that surprising to see Indiana being on par with Alabama.

 

Incidentally, I've been (very slowly) working on some climatology-related stuff for my blog and some of the maps have produced pretty similar results. These aren't final and I haven't thoroughly reviewed the data yet, but it should be close to accurate. All maps are for 1950-2012 and damages are in 2011 USD. Click for larger versions.

 

 

Cool maps

 

It is interesting how IN/AL have been involved in some of the worst outbreaks.  For Indiana I am obviously talking about 4/11/65 and 4/3/74.  Our neighbor to the west, arguably more prone to tornadoes overall, had some in those outbreaks but missed out on the worst of it in both instances.  It's probably more dumb luck than anything as a minor shift to slower timing would've put the heart of those outbreaks farther west.  

[Hoosier]

BTW, with respect to the Indiana posters, this outbreak did something kinda interesting.  Although the Lafayette tornado mostly impacted non-residential areas, it technically passed within the city limits and with the tornadoes in Kokomo and Lebanon, it is the first time that all 3 cities have been hit in the same day...or at least the first time that it's been documented.  Here's a list I put together...done to the best of my ability given some issues with data.  Asterisks mark those that I'm not confident about.

 

 

Lafayette:

 

6/13/1953 - F1

3/19/1971 - F2*

4/1/1974 - F2

4/10/1978 - F2*

4/23/1978 - F1

6/25/1978 - F3*

7/2/1978 - F1

6/7/1980 - F2

6/24/1981 - F1

6/8/1993 - F1

6/11/2003 - F0

7/21/2003 - F0

11/17/2013 - EF3

 

 

Kokomo:

7/9/1951 - F2
3/6/1961 - F3
4/11/1965 - F4
6/15/1976 - F0
7/7/1977 - F?*
4/20/2004 - F1
11/17/2013 - EF2
11/17/2013 - EF2
 

 

Lebanon:

2/25/1956 - F2*
8/25/1965 - F2
5/27/1973 - F2
7/4/2003 - F0
11/17/2013 - EF2
 

[KokomoWX]

A friend of mine went up and took aerial photos of Kokomo.  I posted them on Facebook - https://www.facebook.com/media/set/?set=a.575628402509261.1073741827.143290179076421&type=1&l=be15556fe7 

[tornadotony]

With LOT's addition of an EF0 satellite to the Washington-Dana-Long Point tornado near Dana, that's 75 tornadoes for the outbreak.

[Hoosier]

Final numbers are in. 

 

There were 2 late additions for Indiana, 1 by IWX (EF2 in White county) and 1 by IND (EF1 in Tippecanoe county).  The EF1 in Tippecanoe county brings the outbreak total for the county to 6 tornadoes, which is the most tornadoes on record in any county in Indiana in a single day.  The Indiana total for the outbreak is up to 30, which makes it the 2nd largest outbreak on record behind June 2, 1990.  Out of the 30 tornadoes, 14 were EF2 or greater (I'm including one tornado that's listed as EF0 but writeup says was EF2) which makes it the 5th outbreak on record with a double digit F/EF2+ tornado count...the others being 4/11/1965, 4/3/1974, 6/2/1990, and 11/22/1992.

 

For Illinois it appears the final count is 25.

 

For Ohio, there was 1 new tornado to bring the total to 6.

 

For Michigan, it appears that the skipping EF0 in the GRR cwa is being counted as 1 tornado.  Also, a preliminary tornado in Ingham county seems to have been removed. 

 

Numbers in the other states affected don't appear to have changed.

[Hoosier]

Amazingly, all 30 of the Indiana tornadoes occurred in about 1 hour and 40 minutes (when accounting for time zone differences in the state).  Bigger outbreaks have typically occurred over several hours or even most of a day.