Where did the strong tornadoes go?

[Paul Lemery]

It sure seemed like a dud of a May for me as most of the activity was out of reach in the far western plains. Most of the time even if there was a tornado it was most likely only a brief landspout or F0. Accuweather just came out with an article that shows this was the first May since 1950 to not have a tornado that was F3 or stronger. May also had the 8th fewest overall tornadoes with 25, which was still well ahead of crappy 2020 when there were only 10. Add to it that we are currently in the midst of the longest period in recorded US history without an F5 (8 years) and you have to start to wonder if and when it will ever get back to the good old days. I would probably have more luck winning Powerball than seeing a discrete plains supercell with a long tracked F4 in tow. Link below to article.

May Snaps Long-Standing US Streak for EF3 Tornadoes | AccuWeather

 

[Andy Wehrle]

I mean...tornado ratings are partially a function of what they hit. I strongly suspect at least one tornado from that NE cell which I missed (sob) on May 26 was capable of at least EF3 damage. The Selden one from a couple days earlier might have briefly been, as well, at some point outside of the town.

That said, there's no question this May and spring as a whole have been well below average for tornado activity.

 

[Warren Faidley]

I would not pay too much attention to anything Accu-Wx says. Their experts called for an above average season, and we know where that went. This year, the RH was not interrupted so it pooled / backed-up to the mountains of New Mexico and Colorado, where orographic lifting and psuedo-drylines made up for the lack of major lifting mechanisms. Weak shear, outflows and high capes did the rest, mostly short-lived, rain-infested tornadoes, with a lot of LP structures. We were lucky even those events occurred.

 

[JamesCaruso]

Accu-Wx may not be too credible in the long-term forecasting department, but there’s no reason to doubt the historical statistics in the article. In fact, according to a post by @Bobby Little in the State of the Season thread, SPC posted on Twitter the same stat about lack of EF3s.

Interesting to consider whether Selden and/or Nebraska might have been EF3s if there were damage indicators at the time. I can’t comment on Nebraska because I missed it, but I was at Selden. It’s possible the tornado may have initially been stronger before it entered the town (probably not after it exited) but damage was rated a maximum of only EF1 in town so I doubt it was ever two ratings higher. Still, the lack of EF3s in May 2021 is an interesting measure of the lack of activity - fewer strong tornados, lower probability of interacting with damage indicators.

In any case, the lack of EF5s for 8 years is notable, since a period of time that long would allow the averaging out of strong tornados that both did and did not interact with structures.

 

[Mike Smith]

Here is a Capital Weather Gang article on the same topic: https://www.washingtonpost.com/weather/2021/06/12/no-severe-tornadoes-may/

There is a significant downward trend in violent tornadoes, likely due to the warmer climate. Classic global warming theory says the poles warm more rapidly than the tropics. That would mean less energy for violent supercell tornadoes.

 

[Paul Lemery]

Here is a Capital Weather Gang article on the same topic: https://www.washingtonpost.com/weather/2021/06/12/no-severe-tornadoes-may/

There is a significant downward trend in violent tornadoes, likely due to the warmer climate. Classic global warming theory says the poles warm more rapidly than the tropics. That would mean less energy for violent supercell tornadoes. View attachment 21845

Didn’t well respected global warming scientist and the IPCC say we would have more and stronger tornadoes because of global warming? Hurricanes too? I just wish they would have had their story correct before I blew a load on another upgraded chase vehicle. As it is it seems like we are left with another central
plains year bust like 2020. It’s June and already thinking about next year.

 

[JamesCaruso]

It’s June and already thinking about next year.

Don’t spend too much time thinking about it. That’s the whole problem with this hobby, we get so emotionally invested all year long, anticipating a short window of opportunity that disappoints more often than not.

 

[Warren Faidley]

For those who can, I might suggest broadening your chase ranges or types of storms -- at least until (if ever) the pattern is more active. If I only had supercells to chase / photograph over the course of 34 years, I would have gone nuts. (Legal disclaimer that I already am). If you think this is hard, just remember those who chased in the pre-mobile radar / limited wx data years. Even if you lived in / close to Tornado Alley, you wasted a wealth of time waiting and driving, for months on end.

There is great lightning and other foul things to pursue during the monsoon in AZ and New Mexico. Even a hurricane is fun to chase, and you can always pick and choose according to your Cat-level comfort.

 

[JamesCaruso]

Growing up in Queens NY (one of the five boroughs of NYC but geographically on western Long Island), hurricanes were actually my first weather fascination when I was a kid, and then in particular when Gloria hit in 1985. I liked thunderstorms as early as I can remember, and of course they were pretty much just garden variety in that region. My tornado fascination started with a vague notion that it would be cool to see one someday, just as a one-time bucket list thing, but after dabbling in it on one of the original chase tours in 1996, here I am 25 years later and still at it.

All of which is to say, I do enjoy other storms, including nor’easters, snowstorms, hurricanes, and regular thunderstorms (although I’m not all that interested in driving hundreds of miles just to see an ordinary one on the Plains, or to watch one for 3+ hours). Even a plain old rainy day Is pleasurable to me; I would hate to live somewhere like Southern California where the weather is sunny every day (no offense to anyone that lives there, I would just be bored with the weather).

I would love to chase a hurricane eye landfall, but I continue to be perplexed by the logistics, i.e. finding a place to stay and being able to drive into an area that has been evacuated. In any case it’s impractical right now, I can’t just take off from work for what may need to be 5+ days with little or no notice. But maybe someday when I retire. Until then, I’ll try to enjoy the ones that brush by the NJ coast or tropical systems that track inland, like Isiaias (sp?) in 2020.

 

[Jeff Duda]

Didn’t well respected global warming scientist and the IPCC say we would have more and stronger tornadoes because of global warming? Hurricanes too?

If you can provide a link to this statement, I would definitely be interested in reading specifically what was said. My understanding of the impacts of climate change on severe weather is that environments should become thermodynamically more favorable on average owing to the warming atmosphere and the implications from the Clauseus-Clapeyron equation. But dynamically, with higher latitudes warming faster than lower latitudes, thus weakening zonal temperature gradients, jet streams should become overall weaker but more wavy, which could go either way as far as support for severe weather environments.

Beyond that, legitimate discussion on the impacts of climate change on severe weather is only relevant on the synoptic scale and larger. Forecasting supercells and tornadoes will always remain difficult regardless of background climate, and I can't, at this time, recall any published articles claiming tornado counts per se, are statistically significantly likely to increase. If you heard someone say that, they may very well have been being hyperbolic or alarmist in trying to draw attention.

In any case, the lack of EF5s for 8 years is notable, since a period of time that long would allow the averaging out of strong tornados that both did and did not interact with structures.

There was also a 8 year gap in (E)F5s from 1999 to 2007 (Bridge Creek/Moore to Greensburg), so such a gap is not unprecedented.

It's difficult to get EF5 tornadoes. That's not necessarily because it is difficult for the environment to produce such strong winds (I suspect there are quite a few more tornadoes, perhaps 100% more per year, that contain EF5 winds in them at some point), but because there are so few DI-DoD pairs in the EF scale capable of "resolving" EF5 damage, and so such damage is observed infrequently.

 

[James K]

Interesting articles. Its something I had not noticed personally, I guess I was looking more at the fact tornadoes were occuring, & not the strength of them..

There is great lightning and other foul things to pursue during the monsoon in AZ and New Mexico. Even a hurricane is fun to chase,

I personally love a good lightning show (truly one of my favorite parts of summer) -- for the few we get here -- and nature seems to be providing less of those these days too than it used to?
But that said, lightning shows to me is more something I see as to sit at home & watch than something I'd 'go after'.
It also seems 'monsoon season' here in CO isn't what it used to be years ago? Could simply be my imagination/poor-memory but it seems like we used to get more out of it? (though maybe something like this is more a discussion for a monsoon thread...)
And I would love to see/experiance a high end hurricane - particuraly the eyewall & inside the eye (thing is you'd need some sorta hurricane-proof bunker, plus a way to 'get out' & head home as soon as the storm was done)

Didn’t well respected global warming scientist and the IPCC say we would have more and stronger tornadoes because of global warming? Hurricanes too?

Something like that (stronger/more violent storms as a general thing) is what I seem to remember hearing about with global warming as well.

 

[Drew Terril]

To add to Jeff's point, the more stringent and consistent means by which storms are rated, even compared to 20 years ago, likely make a significant difference, as far as the amount of time since the last EF5. There is far more consistency in ratings from one nws office to the next as far as how they rate storms, and for every storm that could be argued in that span since 2013, there was always an extenuating factor that left the rating lower. And I'm fine with that. It should be difficult to rate damage as EF5 damage. And as someone who spent a fair amount of time working in construction and understands that side of things (as opposed to seeing things from a met perspective), I'm glad to see the consistency across the board.

 

[Jeff Duda]

Speaking of publications on the impacts of severe weather due to climate change:

https://twitter.com/x/status/1404885725070323716