Tornado Stats Reference Sheet

[vortex95]

I put this tornado stats sheet together recently.  Always good to know the

absolute extremes and what nature is capable of.  I carefully checked things

and cross-referencing for accuracy, but let me know if anyone see something

that doesn't appear correct.

Still awaiting full NWS survey for the long tracked tornado in MS/TN on 12/23.  Initial

report is 145 miles, but from chaser accounts it seems this was more than one tornado.

Still this could be a 100+ mile single tornado segment within that track.

 

You may notice the 3/18/1925 event (Tri-State Tornado) listed here is "only" 151 miles

when many books and on-line articles state 219 miles or more.  From a detailed study a

few years ago, the longest track segment that has the strongest evidence of no gaps is

151 miles.  You can read all about it here (small PDF link at the bottom).

http://ejssm.org/ojs/index.php/ejssm/article/viewArticle/109

 

Either way, 151 miles is still the longest track on record, and falls within the limits of what

has been observed in recent decades.

 

And I looked back through Grazulis' "Significant Tornadoes 1880-1991" (aka the Big

Green Book).  He pointed out that many long tracked tornadoes over 100 miles in

NCDC database were actually likely two or more tornadoes from the same supercell,

and he made it a point to parse out these carefully as well as he could, so I have not

included any 100+ mile tornado he listed as a "family".   Incomplete tornado surveys for

long track events were an occasional issue right through the early 1990s, latest being a

160 mile track "single" tornado in ern NC on 11/23/1992. Around this time, the NWS

Modernization was well underway and completed in the next couple of years.  Since this

time, tornado surveys have become much more detailed and complete.

 

A note on widest tornadoes...prior to about 1982, *average* tornado path width was entered

in the NCDC database by some NWS offices.  Since then, the only the widest path of

any tornado has been entered, so there is bias to more recent decades as to the

widest ones.  Also, the highest number that can be entered for a path width of a tornado

for the NCDC database is 9990 (feet) (both from Grazulis' book "The Tornado: Nature's

Ultimate Windstorm").  So you will not see a tornado listed any wider than 1.9 miles there,

even though there has been several 2 mile wide or more events.  Not sure if this has

been corrected in recent years with very wide tornadoes, but going back and correcting

earlier data sets in the official NCDC database is not always as 1-2-3 as it would seem.

 

EDIT: update file for two missing 100+ mi tornadoes

tornadoquickstats.txt

[Hoosier]

Seems to be some tornadoes missing from the 100+ mile list.  I can think of a couple from here in Indiana -- the 4/3/1974 Monticello tornado (F4) that traveled 108.7 miles and more recently, the 9/20/2002 F3 tornado that was on the ground for 112 miles and passed through Indianapolis.

[vortex95]

Seems to be some tornadoes missing from the 100+ mile list.  I can think of a couple from here in Indiana -- the 4/3/1974 Monticello tornado (F4) that traveled 108.7 miles and more recently, the 9/20/2002 F3 tornado that was on the ground for 112 miles and passed through Indianapolis.

Ok, thanks for the input.  I figured the 100+ mile tornado track list was going to be the one that has the errors or missing events!

[vortex95]

Seems to be some tornadoes missing from the 100+ mile list.  I can think of a couple from here in Indiana -- the 4/3/1974 Monticello tornado (F4) that traveled 108.7 miles and more recently, the 9/20/2002 F3 tornado that was on the ground for 112 miles and passed through Indianapolis.

The 2002 tornado I missed, so I added than in.  The 1974 one I did see in "Significant Tornadoes" and it is listed as a family or

probably 3 tornadoes with a 121 mile track,  However NWS IWX shows two tornadoes, with the start of the path cut short

by a violent RFD taking the tornado out.  Then a second one formed near Brookston and goes the 108.7 as one tornado.  I'll go

with that length in the file.

[andyhb]

Clarksdale to Selmer, TN track has been confirmed to be two tornadoes. Looks like we won't have a replacement for the longest (confirmed) tracked cold season tornado.

[Quincy]

Ok, thanks for the input.  I figured the 100+ mile tornado track list was going to be the one that has the errors or missing events!

Ian put this graphic together of 100+ mile trackers since 1950: