Remembering A Pair Of Significant April 19 Outbreaks

April 19, 1996 - 13 tornadoes

Map of Tornado Tracks

April 19, 2011 - 29 tornadoes

Map of Tornado Tracks

Map Of April 19-20 Tornadoes

Updated Information On April 19-20 Tornado Outbreak

First off, you can view the original summary of this event here.

The following changes were made to this outbreak:


-NWS North Webster changed their preliminary ruling of 2 tornadoes in Cass County to microbursts.

-NWS Paducah added a 5 mile long EF1 tornado from Warrick to Gibson counties.

-NWS Indianapolis added 2 tornadoes, a 3 mile long EF0 in Tippecanoe county and an 11 mile long EF1 in
Knox county.

-NWS Indianapolis extended the path of the Vermillion county tornado into Montgomery county for a total path length of 31 miles.  It was also downgraded from EF2 to EF1.

-NWS Indianapolis downgraded the Tippecanoe county EF2 to EF1.

-NWS Louisville added 2 tornadoes, a 2 mile long EF1 and a 3 mile long EF0 in Jefferson county.


There was a net gain of 3 tornadoes, increasing the total from 26 to 29 but still ranking this outbreak as having the second most on record.  Here are some updated stats:


Tornadoes by NWS area:

NWS Louisville:  19
NWS Indianapolis:  5
NWS North Webster:  3
NWS Paducah:  1
NWS Wilmington:  1


Tornadoes by intensity:

11 EF0
16 EF1
2 EF2

26 Tornadoes Confirmed In Tuesday-Wednesday Outbreak, Second Most On Record



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Wow, what an event.  With a total of 26 tornadoes, this is the biggest April outbreak on record and the second biggest in any month (37, 6/2/1990).  I had discussed the chance of tornadoes in a previous post but I was not expecting something like this, especially since the storms had transitioned into a more linear mode by the time they moved in from Illinois.  In a counterintuitive twist, with the instability/shear parameters being very favorable for tornadoes, perhaps the linear nature helped this outbreak be so prolific since it was unfavorable for long-lasting circulations/single tornadoes? 

Where should this outbreak rank among the all-timers?  Most of the tornadoes were relatively brief with no real standout, although total damage is still likely to run into the millions of dollars.  26 is certainly an impressive number, but despite being the second biggest outbreak on record, there were no violent tornadoes and only 4 EF2's.  Part of the problem in trying to compare modern outbreaks to those in past years is that more tornadoes are documented nowadays.  This event had more documented tornadoes than the 1965 Palm Sunday Outbreak and even the Super Outbreak, but I can't possibly claim that this one should rank among those.  Any attempt to rank outbreaks should employ a more complete approach than just looking at raw count, but even then you're at the mercy of imperfect data.  The lack of a violent, long track or high-impact tornado will make this event a little less memorable, but make no mistake, this was an impressive day that deserves to be recognized and remembered for many years to come.

A few notable aspects of this outbreak:

- 18 out of 26 tornadoes occurred in the 75 minute window between 11:15 PM and 12:30 AM

- Dubois county had 5 tornadoes, tied for the most in any Indiana county in one day since records have been kept.

- Anti-photogenic to the extreme - we're going on 4 days and I still haven't seen any pictures/video of a single tornado (Illinois footage doesn't count!).


We now stand at 30 tornadoes for the year, which is already above average.  With an active pattern continuing for the forseeable future, we will probably add to this total in the coming days.  Stay tuned...

21 Tornadoes Now Confirmed In Indiana From Tuesday-Wednesday Outbreak

The National Weather Service in Louisville has confirmed 7 additional tornadoes, bringing the state total to 21.  Here is the breakdown by area and intensity, subject to future modification as surveys are still ongoing.


NWS Louisville:  13
6 EF0, 5 EF1, 2 EF2

NWS North Webster:  5
2 EF0, 3 EF1

NWS Indianapolis:  2
1 EF1, 1 EF2

NWS Wilmington:  1
1 EF1

At Least 15 Tornadoes Confirmed From April 19-20 Severe Storms

National Weather Service personnel from North Webster, Indianapolis, Louisville KY and Wilmington OH have been surveying damage from Tuesday's storms and so far they have found 15 tornadoes.  The breakdown by area is as follows:

7 NWS Louisville
5 NWS North Webster
2 NWS Indianapolis
1 NWS Wilmington


This information is still preliminary and it is possible that additional tornadoes may be found.  Even if nothing else is found, this already goes down as one of the biggest April tornado outbreaks in state history in terms of raw count; it also surpasses a well-known outbreak that occurred exactly 15 years earlier on April 19-20, 1996.  It appears that many of the tornadoes were rain-wrapped and/or brief, and we are fortunate that most of them were of the EF0 or EF1 variety.  Still, this was a rather impressive event.

I will have more on this outbreak in the coming days.