Chase Season 2021 In Review

Jan 7, 2006
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It would be interesting to go back and evaluate long-range model accuracy for this odd season. Glancing through the posts in this thread, several of the long range predictions were in error. I'm still waiting for the "amazing" season Accu-wx predicted. Maybe they were talking about the monsoon? lol
Without looking at objective verification stats, I'd argue the worst subjective flaw in medium-to-S2S range modeling this year was the month-long stretch from early April to early May when there was always a classic Plains severe weather pattern in the offing at days 10-20. Of course, it never materialized in any form or fashion. (Yes, there was a stretch of chase opportunities from about May 15-25, but they came admist a pattern that was far from textbook and bore little resemblance to aggressive medium range predictions earlier in the season). Since the second week of May or so, NWP depictions of the big picture for the 1-2 week range have seemed to settle down and have performed reasonably well. In fact, nightly GEFS runs even nailed the nauseating, detestable June that's now all but locked in.

From my post 30 days ago:

The 00z GEFS now integrates out to 840 hours (35 days, for those keeping count at home), and essentially every run asymptotes toward an upper high over Chihuahua and trough over Quebec as the primary NA features at 500 mb throughout weeks 3-5.
Bear any resemblance to the 500 mb analysis the past week, or the 500 mb forecast for any snapshot from any ensemble run you can pick over the next two?

The fact that seasonal modeling from 6+ months out, along with the GEFS 4-5 weeks out, had such strong signals for this kind of outcome is something I can't get off my mind. With the usual disclaimer that I have no formal background in climate or even S2S modeling, it stands to reason there's something in the boundary conditions (meaning SSTs, land/soil state, polar sea ice, etc.) that made this predictable, even as certain teleconnections at times argued for classically active periods this spring. The burning question for all of us, of course, is how persistent the cause(s) may or may not be as we move years into the future.
 
Jan 7, 2006
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Here's an example:


I seem to recall 2005 was regarded as a pretty bad year for chasing, and yet this happened in June. In good years during that stretch, a day like this would be relegated to the "honorable mentions" section of someone's year-end highlight reel.

Had something like this happened in 2021 (May 26th was close, but not the same), you'd have people with this facial expression the entire time they were typing their REPORTS thread post:
View attachment 21836
🤣

I really do think the obvious lowering of standards, both for forecast events and post-events, is a good, holistic marker of how things have changed over the past 10-15 years. There are plenty of non-meteorological factors that may contribute, but still.

A few times over the past week, I've loaded the latest ensembles and quickly found myself an ill advised click away from a social media tirade that wouldn't be worth the blowback... so I've decided to redirect that saltiness toward pushing along some ERA5-based season scoring efforts I dabbled in last summer. Here's a tease illustrating just how far the month of June has fallen:

env_timeseries.scplainsbox.2012-2020.png

In short, this suggests that between 2012-2020, the entire month of June underperformed 1950-2020 climo as a whole by a large margin WRT coverage of reasonably favorable Plains environments. For early-mid June, 2012-2020 mean coverage is frequently under the 5th percentile for what you'd expect of random 10-year draws from the full 60-year distribution. Also plainly evident is the mid-late May spike in favorable environments, corresponding to what many of us have called the "compressed seasons" of recent years. Basically, it's been a good period to chasecation within the traditional May 15-30 window, but middling to awful outside of that. In fairness, early-mid April have also offered favorable environments significantly more often than the 60-year climo as a whole, although the absolute payoff to chasers so early in the year is fairly limited.

Now consider that when I'm able to add 2021 in a few weeks, the 10-year running coverage for June will very likely -- astoundingly -- fall even further. For all the talk of the sky falling and climate change wiping out all convection that can at times have an irrational, knee-jerk component, June is the segment of the core Plains season I'm really worried about going forward. This run the past 10 years is appalling from just about any perspective. When you combine the empirical data on environments over the past decade with fairly uncontroversial impacts from AGW, including warming Gulf SSTs (e.g., the NHC talking about moving the official start of Atlantic hurricane season to mid-May), there's a lot to unpack.
 
Apr 13, 2009
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I'm always out more or less the last 2 weeks of May. This year I had some success in eastern CO and also caught Selden. Of course, I made some mistakes. Leaving the storm near Kim in particular stings. But there is always more to learn.

It wasn't by best year, but it was so much better than 2017-2019, so I'll take it!
 
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Oct 10, 2004
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Nice, if depressing, work there @Brett Roberts . This suggests an objective decline in recent chase season quality, at least for June, independent of an individual chasers' luck/skill in timing their vacation/scoring on localized/"mesoscale accident" setups.

In 2015-16 I timed my vacation for the first week of June because it historically has been a good period for the C/N Plains and upper Midwest. Obviously this was not a good period of time to do that.

Your note about warming Gulf SSTs is interesting because I had hopes that would help ameliorate early season moisture issues. However it doesn't seem to be the case, or else other negative factors are overwhelming it, because we have seen three of the past four springs (2018, '20 and '21) plagued by moisture quality/depth issues even deep into May.
 
Mar 6, 2019
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Mesa, Arizona
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I have a somewhat rosier look on this season than others, but my bar has always been pretty low. I started chasing in 2012, and with the exception of 2020, I've chased every year since. I don't believe I've ever been on the storm or tornado "of the year/season" due to not living in the Plains and being restricted by work or, for several years, school. Given how frustrating 2019 was and that 2020 was non-existent for me, my bar may have been set a little lower this year, but I feel that my view of this season comes from a more probabilistic mindset when it comes to forecasting and chasing. Additionally, I've gotten more into photography, so I'm happy just seeing a well-composed, beautiful scene and don't need the "THE MOST [ADJECTIVE] [ADJECTIVE] [ADJECTIVE] STORM/TORNADO EVER" to consider a chase a success. I saw a couple of tornadoes, a couple of good storms, new places, and in general experienced new things, so I'm content with my spring 2021.

Through my 11 day period (May 18 - May28) out in the Plains, it seems like the most of the storms of the day were low-probability, high-reward targets that even in hindsight, I'm not sure if I would have gone after. And I'd argue that the "high-reward" mostly comes from seeing something almost completely by yourself while nearly everyone else is on the main target a couple hundred miles away. I've chased plenty of setups like that before and ended up with a blue sky or complete crap of a storm while the main target verifies nicely. While I understand they're low-probability so they're not going to verify often, it's just not worth it to me to go after anymore.

I'm fairly happy with the targets I picked, with the exception being May 26. The environment was definitely conducive in SW/W Kansas where I sat most of the day, but from what I recall, the CAMs were more consistent with convection in the TX Panhandle and along the KS/NE border in the days leading up, and then central KS the morning of...all locations that experienced supercells and tornadoes that day. I was able to salvage the day by heading north and catching some structure as the sun set, but it was a frustrating day that I started dreading when I woke up. The bigger the hype, the harder the fall.

While not living in the Plains greatly limits chasing potential, and putting all your eggs in one basket by picking a week or two each year can be risky, I do like the idea of making the trip and basically being "forced" to chase. I'm not going to drive 12 hours from home to chase a marginal setup in CO, but if I'm already out in the Plains, then why not. I've gotten some great storms on marginal setups. With that logic and that this year was a bit of a redemption after the last couple crappy years, I'll give 2022 a spin.
This is almost exactly where I am coming from. A bad day chasing is better than a good day working!
 
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Mar 30, 2008
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Had something like this happened in 2021 (May 26th was close, but not the same), you'd have people with this facial expression the entire time they were typing their REPORTS thread post:
View attachment 21836
I think that is how I looked on Monday while sitting in my car outside of my hotel in Longmont enjoying some Colorado items when I looked over and saw a tornado.
 
May 28, 2011
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Omaha, NE
🤣

View attachment 21837

Now consider that when I'm able to add 2021 in a few weeks, the 10-year running coverage for June will very likely -- astoundingly -- fall even further. For all the talk of the sky falling and climate change wiping out all convection that can at times have an irrational, knee-jerk component, June is the segment of the core Plains season I'm really worried about going forward. This run the past 10 years is appalling from just about any perspective. When you combine the empirical data on environments over the past decade with fairly uncontroversial impacts from AGW, including warming Gulf SSTs (e.g., the NHC talking about moving the official start of Atlantic hurricane season to mid-May), there's a lot to unpack.
Extremely interesting stuff, Brett. Pretty much confirms our anecdotal speculation that the season is growing shorter and June chasing is all but a distant memory. Outrageously depressing for those of us north of I-70 that depend on the month of June for most of our setups. The best chasing of the year used to happen about this time, when crowds and storm speeds are taken into account.
 
Feb 20, 2019
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Brett, I'm curious, can you do the same analysis on Dixie alley? Like western MS over to central GA between Tennessee and a Hattiesburg-Dothan-Valdosta line? It seems to me that Dixie has been ramping up a bit more, tornadoes used to be a bit rarer in Georgia it seems, but I was also paying much less attention until recently.
 
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Jeff House

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Jun 1, 2008
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I moved from the Plains to the South to enjoy the new regime favorable to Dixie Alley. Just kidding!

First half of my time in the South I had better luck being a Plains snob and just chasing on vacation in May. That has not worked out well in more recent years, except 2019. Perhaps I should evaluate chasing the South more early season. It's messy, but it's close.

May climo is that perfect blend of still synoptic influence and the beginning of mesoscale enhancements. May features just right temps aloft (vs nuke cap) and high dewpoints below. However that delicate May balance may be subject to climate change.

June I believe still happens, but location is TBD. We've seen Wyoming and Montana magic, even when the Dakotas and Nebraska are quiet. This year seems to be Iowa into Hoosier Alley. June moisture will be there. Dynamics will not. It's always been about the mesoscale. Just have to find it.

I'm toying with the idea of the South early and June late, skipping May crowds. Honestly with school aged kids, end of school May does not work well anyway.

This year we did go out late season. June 24 from Marysville, KS we saw about what @Todd Lemery saw (State of Chase Season thread). Note neither of us bothered to post in Target Area, lol!

I liked the lack of crowds in June, esp north of I-70. June 25 a Friday we saw more local chasers in eastern Kansas. Iowa to Hoosier Alley is not too crowded either. Oh yeah, it's closer to me too. I could do more June-ing.
 

Drew Terril

Staff member
My season never got off the ground. Only one setup within a 6 hour drive lined up with a day off work, and I had worked all night and wasn't willing to try for the TX panhandle on limited sleep. Everything else on my off day was too far for me to make it back in time for work. Par for the course with my job though, and once I start classes again, it'll likely be an even tighter crunch on my flexibility to chase. But I generally have success during the fall (moreso than spring many years), so I haven't given up on seeing something in 2021.
 
Jan 7, 2006
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SPRING 2021 TAKEAWAYS:

- Yet another down year in terms of classically favorable patterns and environments on the Plains.

- Relative to the pattern, though, I'd say this spring was impressively productive in terms of the tornado-day count (and even quality-tornado-day count).

- With nearly incessant eastern Canada troughing, most of the action was shunted SW into the southern High Plains; W TX in particular had its most productive season in quite some time.

- Another repeat theme from recent seasons was the sharp mid-late May peak, which offered the only sustained stretch of chase opportunities. Still, both April and June at least had a small handful of solid, overperforming setups.

- The month of June as a prospect for sustained, quality chasing and traditional Plains setups continued its death spiral. More on that at the bottom of the post.

- Overall, I think hardcore chasers will remember 2021 somewhat fondly as a season that made lots of lemonade out of lemons; more selective folks will remember it as yet another in a string of seasons that never got off the ground and busted virtually every time there was potential for even a borderline obvious tornado setup (5/23, 5/26, 6/24).

MY PERSONAL SEASON:

- Easily my best spring since 2016, which isn't saying a ton. Four tornado days that were all solid in quality, along with a few good to great structure days.

- I had at least one quality tornado day in each of April, May, and June. After 16 years, the only other spring seasons I can say that for are 2010 and 2015.

- In light of the background pattern and setups, I most definitely view luck as having been on my side this year. I easily could have sat out or otherwise botched any of my tornado days had a butterfly in Madagascar flapped the wrong way that morning.

- My success rate was still low, as it's tended to be lately. Like many addicts, my standards have sunk quite a bit during this era of scarcity since the mid-2010s, and I somehow find myself 4-8 hours from home at times for nothing more than hope-and-pray setups. This year, I felt like that approach actually paid off nicely with ~30% of those setups going off, as opposed to the pure punishment it delivered in 2018 and 2020.

- In keeping with the prevailing synoptic pattern, I saw tornadoes in areas I haven't before, most notably my first in NM and farthest west (105 W). The Vernon (4/23) and Sudan (5/16) storms were also in areas where I've had minimal success over the years, having come to associate the NW TX/South Plains region with inevitable HP grunge until now.

- With all that said, I'm still left pining for something halfway near a typical active season from the 90s-00s. Maybe it's just me, but half the enjoyment derived from legendary chase days is the anticipation, and it's been *years* since we've had something to drool over for several days in advance that actually delivered the goods.

OBJECTIVE SUMMARY BASED ON ERA5 REANALYSIS:

I'm still tweaking and honing a technique for tracking "chase-favorable environments" in the ERA5 reanalysis dataset, which now covers 1950-present. Details aside, what I've got right now identifies grid points where CAPE, bulk shear, and LCLs are at least reasonably supportive of tornadic supercells, and CIN is not prohibitive. This is vaguely like SCP, but also quite different: low-level shear isn't considered, LCL is considered, and each ingredient's contribution is capped once it reaches a reasonably favorable threshold (e.g., >1250 J/kg CAPE or <800 m LCL). Qualitatively, I'm trying to get at "how favorable was the pattern this year, and how did the pattern evolve through the course of the season?" without allowing more sensitive ingredients like SRH to introduce noise. Also, I'm currently evaluating the environment at both 21z and 00z each day, taking the more favorable of the two at each grid point.

So here's what I've got for March-June 2021 over the Plains. Note that these time series are smoothed over an 8-day window, so you can interpret values as something like: "how active was the week centered on this date?" This year's values are the bold green curve; the 72-year median is black; and all 71 of the other years since 1950 are shown as thin gray curves in the background.

env_timeseries.plainsbox.2021.png

Relative to 1950-2021 climatology, we were doing alright until the end of May: the coverage of favorable Plains environments oscillated around the 72-year median without any huge anomalies. In other words, there were no classically active periods, but any dead periods were also short lived. That's for damn sure more than you could say in 2018 and 2020.

Then, right on cue, the bottom fell out in June. Supportive environments in early-mid June over the past decade have been quite anomalously scarce, and the falloff is especially jarring given the tendency for May 15-25 to be more active than normal over the same period. I may do a longer post with more results from this environment-coverage metric later this summer -- there are likely broader takeaways about our perceptions of Plains spring climo derived from chasing a limited set of years vs. what 70 years of reanalysis can tell us.
 
Aug 9, 2012
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Galesburg, IL
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I can agree with Brett on almost all accounts. While it wasn't my best year from a tornado standpoint, lot of bird farts and stat count padders but I did see a handful of photogenic tornadoes during my season which for me is enough, on a few days. The only day I missed that I regret is the Lockett, TX day, but its a 13 hour drive for me and wasn't feasible to drive from IL for a one day setup alone in April.

Also it was mating season here for birds so I was working on my other hobby which is bird photography/videos which is another thing that I do where the window is short and I have to be here if I want to see it, although the Southern Plains offers up some ops for it, I'd rather not lug around my 600mm lens with the TC on it in my car.

I barely missed Selden, KS which kinda sucked, but there was a lot of great photographic ops and probably easily my best year for photos in several years and the year is only half over. I include winter stuff in there as well, winter is my favorite time for photography, this last winter fire here for photos, every day was like a dream.

Overall I'm quite pleased given how poor the pattern was constantly, I even had a borderline strong tornado (110 mph) touch down a few miles from my home and observe it above good structure, making it the latest in any day I've observed a tornado (11:57pm) and it also crossed over into the next day which was again a first for me.

There have been a lot of decent local setups that were very low end and overperformed as well in most of June and the first 2 weeks of July. I'm hoping the trend continues. I didn't chase a ton this spring as I planned on mostly doing chasecations in May and saving funds, so my success rate was rather high when looking at pure numbers. I had 4 total plains trips though which is 1 more than I usually do, but with friends and car pooling, costs were low. I spent less than $1000 total on gas, rentals, hotels, tolls, and food this season so far (probably more in the range of around $700), so not bad.

I'd say overall as of July 12th, I'm pretty satisfied, I know its not up to the level of stuff we'd see in a year like 2004, 2008, or 2010.....but I'm learning to be happy with what I get, especially when it only costs me 15 or 20 bucks in fuel lol.

I will say though, I am needing a good shot of a closer range high contrast tornado. The Forgan/Sterling City sequence was great, but state park terrain kept me from getting too close. But beggers can't be choosers and I'm sure the fall will offer up some shots (I almost always try to keep a positive outlook when it comes to what might happen). But then again, every chaser on here probably is after that kind of shot, so I can't complain at all again. We are all doing the best we can with the hand of cards we are dealt out! For what the year is, I'll give it a C+ so far. Not ideal, but you chase, and you do your best and sometimes you are rewarded with things like the 5/16 TX event or 6/12 in NM :)
 

Jeff House

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Thank you @Brett Roberts for another solid analysis. Everyone, look at the bottom of the chart. As Mike Smith has stated here and elsewhere, the Plains had some very quiet years, including the late 1970s and parts of the 1980s. Apparently we're in another one of those stretches.

Dr. Fujita proposed the activity rotates around the sub-allies (Plains, Hoosier, South, etc). Do I embrace the local and medium-range (<5 hours) chases of Dixie Alley? I'm just tired of nailing forecasts, only for my tornado confirmed cell to go into awful terrain.

Next is Iowa to Hoosier Alley. Requires travel which makes me bust-risk averse. Well, as we see this year one should chase every set-up. Hard to guess which have better odds. Forecast cheat code / EHI was high 24 hours prior to Iowa 7/14/21 but that's not a guarantee alone.

As for the Great Plains, opportunities arose in May. Seldon KS is one. Southern High Plains sequence is another. Then Locket TX was late April, but definitely in season.
 

Todd Lemery

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Haven’t seen any chase reports here for Iowa 7/14, was nobody out there? 44 TOR reports on SPC, that has to have been one of the bigger days anywhere so far this year...
I’m interested too. For me, Iowa has been a place where storms go to die a miserable death. I wasn’t going to get suckered again. That said, I’m sure some people had the chase of their life that day and I’d love to hear about it. This season isn’t getting any younger!
 
Aug 9, 2012
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Galesburg, IL
tornadoguys.com
Haven’t seen any chase reports here for Iowa 7/14, was nobody out there? 44 TOR reports on SPC, that has to have been one of the bigger days anywhere so far this year...
Its probably a combination of the fact that the event was sort of a surprise for how big it was, hardly anyone chased that I know in Illinois (actually only 1 person I know), and nobody really posts on StormTrack anymore due to twitter. I sadly see this as a dying forum in the next couple years unless people post more. 15 years ago, there would have been 3 pages filled with chase reports by now, but nowadays you are lucky to see one person's report 2 days after an event ends.

I also think it has to do with the fact that on StormTrack there are things called "rules" and you have to abide by them, which isn't hard to do. But for some of these people on Twitter, they can't grasp that concept, so I'd probably rather not see them post here and the whole forum turn into a flame war similar to every time someone breathes on wxtwitter. So in a way I'm thankful to keep the handful of people we have here posting as everyone remains respectful. I can't say the same for Twitter.

Another edit: I know this is getting off topic so feel free to maybe start a new thread or move it admins, but maybe we can find ways to get people to post more on here and be respectful at the same time. I'm not sure, but there has to be a way to get StormTrack more popular again. I'd hate to see this forum go. It's been a lifeline for me to learn and grow since I started chasing in 2003.
 

Michael Towers

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Jun 28, 2007
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I’m interested too. For me, Iowa has been a place where storms go to die a miserable death. I wasn’t going to get suckered again.
My thoughts exactly…with only 1 chase so far this year I decided to go out last Friday (7/9) and give Iowa a shot and was rewarded with elevated junk in North English that I believe became the great photo op for @Ethan Schisler later that night in Illinois. To add insult to injury when I got into work the next day it became apparent I missed perhaps what would have been my busiest day of the year and lost business/income that made it a very expensive chase. I’ve never scored a tornado yet in Iowa and have probably busted over 20 times so when the set-up this week arrived on the heels of lasts week’s fiasco I wasn’t ready to bite on what I thought would likely be another bust so I sat it out and of course it turned out to be an epic day less than four hours from home on what turned out to be a lackluster business day. This is the kind of stuff that drives you crazy and makes making decisions on whether to chase so difficult in the absence of a clearly bona-fide high end set-up. Unless things change 2021 will go down in the books as yet another year I got trolled by Iowa…
 
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