Start of the fall "season"?

[Connor McCrorey]

I'm sure I'm not the only one who has spent all summer desperately checking the long-range models for signs of hope, only to wind up disappointed after each new run. However, for several runs now the GFS has been developing a very large trough over the western US sometime in the next 10 days. As expected, each new run is doing something completely different in regard to how far it makes it into the plains and so on, but it has been very consitent in at least the general timing and location of this feature.

It's obviously too far out to start any sort of forecast thread, but I thought people might be interested in discussing our possibilities in the not-so-distant future. After such a dismal spring, it would be wonderful to get a few good supercells, maybe even tornadoes, this fall!

 

[jeremy wilson]

Man it's hard for me to post in a thread with a big, ugly, orange cow at the top. But I will anyway.

I've been noticing this too Connor. I haven't got my hopes up too much yet but I am hoping for my 2nd fall tornado of my chase career in '09. SDS is kicking my butt!

 

[Bill Tabor]

Probably a little early yet for a "Fall" season as it is still August. Typically at least down here in TX I look for action to start around Oct / Nov but possibly even December. As I recall last few years we started seeing some action near the end of Oct.

That reminds me though, as I turned off all my data services I'll have to get the tether option going with the Iphone for data. Supposedly that is not too hard to do - just a change of a file in Itunes I believe.

 

[Mike Hollingshead]

http://www.rap.ucar.edu/weather/model/displayMod.php?var=gfs_sfc_tmin&hours=hr072hr048

I thought the thread was going to be about that lol. Freaking 30s.

The extended does looking sort of interesting. Forever now(years) the jet just doesn't seem to want a trough to really plow on east worth a darn(yay for cut offs I guess, since we can occasionally get one of those worth a darn...but yeah). Finally get the "twice a year western big trough" (sarcasm, sort of) and it doesn't want to move east. Instead it waits and shears to garbage west of the plains. GFS is doing with it what would be expected anymore. The jet is screwed up. It'll shear it to Canada and revert right back to west ridge east troughing. That song and dance is amazingly old.

 

[Skip Talbot]

lol Mike,

Connor, I too look to the future with eager optimism. However, the GFS has been persistently keeping the good moisture ahead of the trough. You probably don't want to hear this either, but the Dakotas and into Canada look the best (180-204 hrs) provided that the forecasted moisture advection occurs. September in northern plains? Its worked before.

 

[Michael O'Keeffe]

Yep I agree with Skip the N Plains looks the best at this point but the trough is hanging back in the Rockies and doesn't want to move much out into the Plains. If it does though I'd say there is a decent chance for an organized severe weather event from W SD into W KS. As of right now Sun-Mon look best and we should be coming back from Colorado on Sunday so we may need to detour if it begins to look a bit better.

 

[Chad Cowan]

It's going to take a major shift from the pattern we're in to get that long range GFS to verify. My guess is that the more likely solution will be for the strong western ridge to keep that system further north than what the models are showing. Even if we do get a nice trough in the central US next weekend, any decent set up will probably go to waste given the meager low-level moisture for this time of year. It's like early Spring '09 all over again... huge troughs on the east coast wiping the eastern two-thirds of the country dry and any systems that do make it into the Plains have to deal with a post frontal airmass. If that system gets cut off and parks over the w'rn US for a few days we'll get some better set ups with more moisture return, and with the ridge's strength I wouldn't be surprised to see it move east really slowly.

 

[Connor McCrorey]

lol Mike,

Connor, I too look to the future with eager optimism. However, the GFS has been persistently keeping the good moisture ahead of the trough. You probably don't want to hear this either, but the Dakotas and into Canada look the best (180-204 hrs) provided that the forecasted moisture advection occurs. September in northern plains? Its worked before.

Trust me I realize it could be pretty far north... I never said I didn't want to drive a little while

 

[mikegeukes]

September: Tornado Days for the Great Plains 1970-2008 (39 years of data)
07 Tornado Days: September -North Dakota
15 Tornado Days: September -South Dakota
32 Tornado Days: September -Nebraska
37 Tornado Days: September -Kansas
47 Tornado Days: September -Oklahoma
17 Tornado Days: September -Texas Panhandle (AMA, LUB CWA's)
Mike

 

[Tyler Burg]

I figured this would be about the cooler temps as well. I am finding it tough to get excited for any fall setup after a really frustrating summer. Plus now I've got class and wouldn't really be able to chase anyway. Lol and Mikes last post isn't too exciting, only 32 tornado days in 39 years in September, thats not even one a month if you average it out, its .83 tornado days per September on average. I'll take the cooler temps.

 

[Jeff Hawkins]

I've got off of work 9/7-9/11...I'm watching. Not hoping...just watching. Perhaps a Chicago/Midwest group can team up and go IF things look good by 9/5?

 

[Jonathan Behle]

We need to get rid of this Northwesterly Flow before Im too excited..It does seem like we are settling into more of a fall weather pattern and its still August.. What that means for the rest of fall and winter and the second season is still up for debate.

For what its worth, It seems like the less active the spring and the hotter the summer, the more active the "autumn season" is.. With that all said, in Kansas, I really can't think of an active September-October since 2001.. But we had an active fall for 1998 and 2000 also.. Maybe we are due but I never get my hopes up as a fall outbreak is just icing on the cake for a year.

 

[Mike Hollingshead]

Doozy on the 12z GFS for next Sunday lol. That is what spring should look like. 50knt sw 500mb flow over 30+ knot sse 925mb flow and juice. I'd say it is on the right track! Damn it, the roller coaster and let downs to look forward to this week.

 

[Bob Hartig]

Shoot, let's not forget about Friday, 9/11. Only 300 hours out. What can possibly go wrong with that?

Seriously, I haven't much been watching the models lately, so this thread is a nice heads-up. Guess I'll be keeping an eye on how things develop for next weekend.

 

[Andrew Ryan]

Doozy on the 12z GFS for next Sunday lol. That is what spring should look like. 50knt sw 500mb flow over 30+ knot sse 925mb flow and juice. I'd say it is on the right track! Damn it, the roller coaster and let downs to look forward to this week.

The only problem I can see with the setup is the fact that it is in Nebraska! lol Hopefully it will trend southward over time.