Fall chase season?

[Jim Bailey]

I'm hearing alot of "seasons over" type comments on this site, almost always followed by "well, there's always the fall!".

My questions are related to the fall chase season. When does it start, typically? Is it mostly a plains event? If you were planning a "chase-cation" for the fall, when would you schedule it and where would you book a room at motel 6?

Is the fall chase season much different than the spring season? Are the storms less intense, less structured, etc.?

I want to start prepping now and just need a rough timeline to plan around. Thanks for any input on this...

JB

 

[Clarence Bennett]

Can't speak for the plains, but in the Mid-South, it is typically low cape, high shear, moving at break neck speeds. I would go to Jackson, TN. They seem to have had a bullseye on them the last few years

 

[Dan Robinson]

The 'fall season' is when upper flow returns to the central US during the seasonal transition to winter (September to November). There is typically at least one event per year with 'outbreak potential' anywhere from the Plains to the east coast. As Clarence pointed out, it's similar to early spring low CAPE, high shear synoptic-scale setups.

It's a stretch to call it a 'season' as there are usually only one or two events - some years there are none. Tornado numbers-wise, it's probably comparable to the Midwestern summer season. However, it is a time that I start paying attention to models again and be ready to go in case something pops up. I typically get at least one fall chase in per year - so far I have one fall tornado on the books.

 

[Skip Talbot]

As the polar airmass invades from the north, you'll find you're dealing with more cold front setups as well. Cold fronts often lead to less than ideal chase setups as the strong forcing and linear wind fields lead to a big squall line rather than discrete supercells. I don't think I would say, "well, there's always the fall season." The fall season is more like a year end bonus.

 

[Michael O'Keeffe]

I'm hearing alot of "seasons over" type comments on this site, almost always followed by "well, there's always the fall!".

My questions are related to the fall chase season. When does it start, typically? Is it mostly a plains event? If you were planning a "chase-cation" for the fall, when would you schedule it and where would you book a room at motel 6?

Is the fall chase season much different than the spring season? Are the storms less intense, less structured, etc.?

I want to start prepping now and just need a rough timeline to plan around. Thanks for any input on this...

JB

I think I was the one who said that on one thread and I say that because one of my best chases ever occurred in the fall but, the fall is VERY hit or miss and it would be a waste to try and schedule a chasecation for the fall. However you always count on one maybe two events, typically they are hyped up such as Oct 17, 2007 and Nov 5, 2008 both in Oklahoma which were expected major outbreaks only to be nothing more than a few fast moving HP supercells. But you may get a year like 2006 where there were several days in August and September that yielded great, slow moving tornadic supercells including the tornado from my avatar taken in South Dakota on Sept 16. I think 2001 was also quite active in fall with several outbreaks in Nebraska and W Oklahoma.

The fall is almost always active east of the Mississippi though once again extremely fast storm motions and terrible chase terrain make it near impossible to chase.

So like I said you shouldn't count on the fall but there is always a good chance you will find yourself out chasing in the fall but when and where is anybody's guess.

 

[Randy Bowers]

It's usually quite difficult to chase in the fall because of storm mode. Aside from the low instability / high shear aspect and 50+ mph storm motions, the locations where severe weather is most likely in the fall are often not the best terrain-wise. Also, the days are shorter and many times the events really don't get crankin' until after dark. But the Southeast and Ohio Valley have had their fair share of big severe weather events during the fall season. A few dates that come to mind:

10/24/01 - High Risk
11/10/02 - High Risk
11/06/05
11/15/05 - High Risk
10/17/07

Perhaps the best thing to do for these big fall events is to load up GRlevelX, pop a bowl of popcorn, and sit back and watch .

 

[Brandon Goforth]

The 'fall season' is when upper flow returns to the central US during the seasonal transition to winter (September to November). There is typically at least one event per year with 'outbreak potential' anywhere from the Plains to the east coast. As Clarence pointed out, it's similar to early spring low CAPE, high shear synoptic-scale setups.

It's a stretch to call it a 'season' as there are usually only one or two events - some years there are none. Tornado numbers-wise, it's probably comparable to the Midwestern summer season. However, it is a time that I start paying attention to models again and be ready to go in case something pops up. I typically get at least one fall chase in per year - so far I have one fall tornado on the books.

I also don't think I'd call it a "season", as more often than not you're not going to see much action in the fall, at least in the plains. Yeah, we might get a day or two in the plains that produce one or two tornadoes, but good tornado days don't happen too often. Sometimes there are big days, but don't bet on it. Taking a "chasecation" in the fall is a bit of a joke IMO because you're not going to get multi-day chase opportunities like in the spring.

 

[Drew.Gardonia]

western to middle tennessee seem to see some action from October to December, with good 60*, 70* degree temps. they call it Tennessee's 2nd tornado season, and i definitely have to agree with Clarence Bennett....Jackson seems to get nailed every few months.

 

[Jim Bailey]

A big "Thank You!" to all the posters...I understand much better now.

I'm a free-lance photographer by trade and long term planning for me is two days in advance, so the chasecation was just a hypothetical. My real hurdle is my wife, we have two young kids and she thinks that chasing tornados might not be the best use of my time. I was just thinking that, if the fall event was worth much effort, I could show her the rider I added to my life insurance stating that I'm covered while chasing. Now I'm thinking I'll save that info for next spring.

JB

 

[Adam Lucio]

I caught my strongest tornado on the 10/18/07 event. an EF-3 that tore through Nappanee, Indiana.

Sept 22nd 2006 also saw a brief, weak tornado touch down in the heart of Chicago as 3 tornadic supercells moved across northern Illinois. We had 2 years in a row where October 2nd had some severe weather around here.

As others have mentioned, the fall setups are never a sure thing, but they can be big. I can deal with the storm speeds, and Ive seen low CAPE high shear events go bonkers before...the biggest downer is in the fall its dark by 6pm again.

There is usually one last chase to be had in the fall, every year has had one for me.

 

[Derek Weston]

The plains don't have anything consistent enough to be called a fall-season outbreak wise, IMO. (though as someone else pointed out... the shifting of upper air patterns is a signal to start watching for an opportunity)

Based on my observations, the mid south probably has the closest thing to a fall season. And then after that... the mid to late fall outbreaks across the Ohio Valley region. Again, not really a season, but we've certainly seen quite a few healthy outbreaks in Oct-Nov period across this area.

You can also usually count on a good setup or two in the Aug-Sept timeframe across the upper midwest into the upper plains areas.

Last year was rather quiet. But if you take a look back at storm report logs, you'll see some nice setups.

 

[Brian Stertz]

Sure... parts of OK/KS/NE/MO can be relied on for some good fall events....particularly from late September into October. It's not a guarantee, but I would say these areas of the C/S Plains do in fact have a second season... and one worthy of one to three chases (if the pattern is right).

 

[Mike Hollingshead]

September seems to be one of the worst months of the entire year. That is one month towards fall I'd never rely on. I don't think I have any decent structure from that month, let alone a tornado. Of course had I not been watching some recent chase footage at a friends house September 22, 2001 and gotten out sooner, this likely wouldn't be lol(not likely, it simply wouldn't be, given the county or so away start). Doh. Boy we regretted that whole deal. I know Brian remembers that day. They had some of the best structure I'd ever seen on video, plus a mean ol tornado.

I think the most hope probably lies in October. Take October 9, 2001 away and it too doesn't ring a lot of happy chaser bells to me.

November 5, 2005 IA tornadoes were nice but yeah, like that happens but once a century.

Take away the fluke event in Iowa that year and October 9, 2001....and I've really seen jack crap in the fall. That is 10 falls. If only each fall had a October 9, 2001...then it'd be something to look forward to. Instead it is largely like a wishcast. I surely wouldn't count August as fall. August sucks and it still seems better than the fall months.

Of course if you chase like some people out there, that are damn good and really never miss stuff(having great years in bad years) then fall is probably decent. For the more mortal chasers out there, eh, bring on spring.

 

[afischer]

This is probably just anecdotal and may not hold climo-wise, but as far as a "second season" goes... I actually find the last 10 days of August to be more reliable than any particular 10-day "autumn" stretch in Sept, Oct, or Nov. These setups will usually be relegated to the northern plains, but sometimes appear as far south as nrn KS/MO. It seems that maybe 50% of the time, you can count on one or two good discrete supercell/tornado days in the last 10 days of the month. The first half of August obviously is one of the absolute deadest periods of the warm season climatologically w.r.t. supercells and tornadoes in the lower 48... but generally as stronger flow returns to the northern tier, late August can bring a pleasant surprise or two. 08/26/07 (eastern ND), 08/24/06 (SD and MN), and 08/26/04 (SW IA) are some of the more significant examples off the top of my head, and there have been a few others recently as well. 08/16/02 also had some crazy supercell structure in nern NE... and even farther back, 08/15/99 brought some insane damaging bow echos AND significant tornadoes to much of ND.

 

[mikegeukes]

I did some quick research on tornado days for the Great Plains.

I use tornado days instead of actual number of tornadoes, big
outbreak days tend to skew the data.

Example: Tornado Outbreaks for Oklahoma
27 tornadoes on 10-04-98
19 tornadoes on 10-09-01

Only Oklahoma show a increase in tornado days in the fall
an increase from August to September.

Tornado Days for the Great Plains 1970-2008 (39 years of data)

North Dakota:
143 Tornado Days: July
88 Tornado Days: August
07 Tornado Days: September
02 Tornado Days: October
01 Tornado Days: November
-
South Dakota:
133 Tornado Days: July
60 Tornado Days: August
15 Tornado Days: September
06 Tornado Days: October
00 Tornado Days: November
-
Nebraska:
138 Tornado Days: July
67 Tornado Days: August
32 Tornado Days: September
18 Tornado Days: October
02 Tornado Days: November
-
Kansas:
92 Tornado Days: July
57 Tornado Days: August
37 Tornado Days: September
26 Tornado Days: October
10 Tornado Days: November
-
Oklahoma:
33 Tornado Days: July
32 Tornado Days: August
47 Tornado Days: September
40 Tornado Days: October
28 Tornado Days: November
-
Texas Panhandle: (44 counties in AMA and LUB CWA)
40 Tornado Days: July
37 Tornado Days: August
17 Tornado Days: September
10 Tornado Days: October
04 Tornado Days: November
-

Mike ( Still looking for work in Michigan)

Researched by: Mike Geukes
Copyright @ 2009 Mike Geukes