Inconceivable Tornado Season

[StephenHenry]

I've had fun recently playing around with the SPC's full tornado database (you can find the 6MB csv file near the bottom of this page). I really like the "tornado trends" graph that they put out, and I started wondering what the worst conceivable tornado season might look like. Starting with 1990 (I'll call this more-or-less the "modern" era or tornado counts), I strung together the worst months into a single trend. I figured monthly mins provided in nice synoptic average (versus, say, taking the DAILY min).

Can you even imagine what this forum would be like after a 400 count tornado season?!?! We'd all go insane. Here are years that contributed to each month's minimum count:
Jan: 2003 - 0 Tors
Feb: 2010 - 1 Tor
Mar: 2013 - 18 Tors
Apr: 1992 - 53 Tors
May: 2012 - 121 Tors
Jun: 2002 - 97 Tors
Jul: 2012 - 37 Tors
Aug: 2012 - 38 Tors
Sep: 2009 - 8 Tors
Oct: 1999 - 17 Tors
Nov: 2009 - 3 Tors
Dec: 2003 - 1 Tor

 

[Paul Lemery]

I've had fun recently playing around with the SPC's full tornado database (you can find the 6MB csv file near the bottom of this page). I really like the "tornado trends" graph that they put out, and I started wondering what the worst conceivable tornado season might look like. Starting with 1990 (I'll call this more-or-less the "modern" era or tornado counts), I strung together the worst months into a single trend. I figured monthly mins provided in nice synoptic average (versus, say, taking the DAILY min).

Can you even imagine what this forum would be like after a 400 count tornado season?!?! We'd all go insane. Here are years that contributed to each month's minimum count:
Jan: 2003 - 0 Tors
Feb: 2010 - 1 Tor
Mar: 2013 - 18 Tors
Apr: 1992 - 53 Tors
May: 2012 - 121 Tors
Jun: 2002 - 97 Tors
Jul: 2012 - 37 Tors
Aug: 2012 - 38 Tors
Sep: 2009 - 8 Tors
Oct: 1999 - 17 Tors
Nov: 2009 - 3 Tors
Dec: 2003 - 1 Tor

 

[Paul Lemery]

2015 is looking pretty close to the all time historical lows so far.

 

[StephenHenry]

The SPC updated their tornado database yesterday with 2014 data!! Surely everyone else was as excited to see this as I was right? RIGHT??

Interestingly, while 2014 was a slow year, it didn't provide any new monthly minimum tornado counts (though it was very close in February and May), and hence the chart from my first post is still accurate. EDIT: Oops I screwed up a SQL query, turns out Aug 2014 WAS the quietest since 1990 (33 Tors vs 38 in Aug 2012). All other mins were unchanged, though.

@Paul Lemery, we are indeed tracking close to historical lows. The 2015 graph will cross below the inconceivable graph in just a few weeks. SURELY that won't happen.

 

[Adam Lucio]

Over the past couple weeks I found myself wondering how low a count would be if you took all the record low months and added them up together. Thanks for putting this together, as depressing as it is. When it comes to the weather, never say never!

 

[StephenHenry]

Well, we've finally gotten our first taste of spring. Honestly, in a weird way I was kinda hoping to see a tornado-less March, just so I could brag about it in 30 years. Wednesday was a good start, but we need to keep producing or 2015 could still cross below the inconceivable season. Thankfully it looks like we have some additional setups on tap next week!

 

[StephenHenry]

Another natural question to ask is what would happen if we stacked the most active months together into a single year. Here's what you'd get.

Jan: 1999 - 212 Tors
Feb: 2008 - 147 Tors
Mar: 2007 - 170 Tors
Apr: 2011 - 758 Tors
May: 2003 - 542 Tors
Jun: 1992 - 399 Tors
Jul: 1993 - 242 Tors
Aug: 2004 - 179 Tors
Sep: 2004 - 295 Tors
Oct: 2001 - 117 Tors
Nov: 2004 - 150 Tors
Dec: 2002 - 97 Tor

Can you imagine 3300 tornadoes in a year??

Interestingly, four years contributed to both the min and max inconceivable seasons:
1992: Min April, Max June (how fast things can change!)
1999: Max January, Min October
2002: Min June, Max December
2003: Min January, Max May