Warren Faidley
Supporter
Well, if this even comes close to verifying, it's going to be rocking and rolling in the Central Plains for a multiple day event. (Instability is also present).
Major Pattern Change Coming Up ??
- Thread starter Paul Sherman
- Start date
Joerg Kudella
EF1
Our chasecation starts May 13th...I am totally convinced, that it will be a heck of stay for us!!!not a bit worried...
Derek Weston
EF5
The GFS is staying on track with its terrible May. NW flow galore. Mother nature shot her load in April. We're doomed.
Steve Smithson
EF0
My chasecation starts May 21st still 3 weeks away, I'm still hoping for something, I guess this is the only downside to a fixed two week trip.
Steve Smithson.
Steve Smithson.
Steve Smithson
EF0
Just going on from my previous post, I think I remember on two occasions one in 2008 and 2010 someone saying the pattern for May was awful, looked what actually happened a week to 10 days on from those quotes, I've often sat with Jim Leonard while on a chase looking at forecasts far out and he say patterns were looking crappy then a day or so later it's all change and again vice versa, in situations where it look sure fire tornado set up previous evening then all falls apart the following day. It's the same over here in the UK, I often look at the monthly forecast it rarely verifies so I think I'd worry a week before I flew out if NW'ly flows or death ridges were in evidence for last 2 weeks of May.
To be honest, thats the risk of chasing with a set two weeks, Year 1 can be awful but the next can be awesome!!!
One thing is us chasers especially from Europe seem to be bound together by frustration more often than not
Steve Smithson.
Rob Lightbown
EF0
I found some of the commentary at the beginning of Wednesday night's High Instability show quite interesting. In particular, Dr. Doswell mentioned going back through the records and finding 1957 as a analog year and Gene Rhoden mentioned that 1953 may be considered an analog year as well. Reason being for both years is the on-going drought and the entire weather pattern that actually kept going right into the summer, albeit shifting northward with time. Thoughts??
Steve Smithson
EF0
Going on from what I've been told....more Northern Plains chasing and East of the River, shutdown in the Southern States? Surely May 2011 won't be like May 2006 & 2009 total shutdwn will it?
Steve Smithson.
Derek Weston
EF5
I have no way of knowing. Nobody does, really. Hopefully people didn't take my previous post too seriously. As others have mentioned... May 2008 got off to a bit of a slow start and went off roaring down the stretch.
I will say that it's looking like the first week into may is going to be slow if I had to hazard a guess... beyond that, have more hope.
(FWIW, even the SPC is siding with me on the quite first week: http://www.spc.noaa.gov/products/exper/day4-8/)
Steve Smithson
EF0
Well not too seriously Derek only a little concerned as I'm travelling over from the UK, mother nature plays cruel tricks in one way or another and always keeps you guessing right up to seeing the storm and will it, won't it produce I guess thats the fun part of chasing!
Steve Smithson.
only a little concerned as I'm travelling over from the UK, mother nature plays cruel tricks in one way or another and always keeps you guessing right up to seeing the storm and will it, won't it produce I guess thats the fun part of chasing!Steve Smithson.
Mark Ellinwood
EF2
Week one looking less and less exciting per the operational models, with the -AO/-NAO keeping things on the down-low. However, models are still showing -PNA, the effects of which (more ridging+warmth in the Southeast with more of a trough out west) has been underforecast in recent weeks. It will be a battle between the -AO/-NAO and -PNA in driving the pattern going into May, and the models say week one goes to the -AO/-NAO (for now).
Kelly Sugden
The GFS doesn't verify. The ECMWF does. The EC shows troughing out west. UA NW flow can lead to some severe as well. Nice analogy though...
Kelly Sugden
Those indices have low predictability/forecast skill beyond two weeks.
Mark Ellinwood
EF2
Well then it's a good thing I'm not talking about beyond week two
Also, noting from the CPC page, the AO/NAO forecasts have been verifying on the highest or beyond highest forecasts over the last two weeks... time to see if this trend continues (which would give these values closer from tanking as much as is shown in the forecast).
Rob H
EF5
As of right now, the GEFS is pretty confident that NW flow will be in place at least up until 5/6:
I'm familiar with NW flow events in the northern plains/midwest later in the summer, but are there any good examples of NW flow events in spring?
As Kelly mentioned though, the GFS typically underperforms when compared to the ECMWF, which is showing some a nice trough on 5/3:
Statistically speaking, 5/8 is the second best day for tornadoes, so while I don't think I'll be chasing the first week of May, I'm hoping the second week is something special. Watch the last week of frames on this link, and try to tell me that 3000+ CAPE for 8 days straight doesn't at least pique your interest:
http://www.twisterdata.com/index.ph...nding=n&output=image&view=large&archive=false
I'm familiar with NW flow events in the northern plains/midwest later in the summer, but are there any good examples of NW flow events in spring?
As Kelly mentioned though, the GFS typically underperforms when compared to the ECMWF, which is showing some a nice trough on 5/3:
Statistically speaking, 5/8 is the second best day for tornadoes, so while I don't think I'll be chasing the first week of May, I'm hoping the second week is something special. Watch the last week of frames on this link, and try to tell me that 3000+ CAPE for 8 days straight doesn't at least pique your interest:
http://www.twisterdata.com/index.ph...nding=n&output=image&view=large&archive=false
Kelly Sugden
Good info! The point is not a get all fatalistic and call the season over just because of the 384 hr GFS. I have seen countless times where the GFS comes inline to the eventual synoptic pattern as advertised by somewhat consistent output solutions from the ECMWF. Yes, I think the first two weeks do look relatively quiet to what we have seen... although for Kansas... the convective season hasn't really started yet (in my own narrow definition of the real tornado alley -aka high plains) regardless of what has happened in the jungles of Dixie alley. Too much westerly momentum so far! I would key in to the EC which shows the possibility of local severe storms during the first week of May. After that, the EC shows more of a zonal flow which is unstable and subject to amplification...hopefully a big ol' trough out west. Standard caveat of low confidence applies but trends would point to a more active pattern towards the middle of May.
