andyhb

That low level inversion is not realistic (happens time and time again with the GFS), and it's likely cooling the boundary layer too fast.

So if you get rid of that unrealistic decoupling of the boundary layer like the GFS always does at 00z, not much else to say but holy smokes. Depth of the BL moisture could be a bit better on the OK sounding, but man those wind profiles are basically textbook.

Looks pretty favorable as well, although it was further south for Tuesday last night (closer to the Red River Valley).

Popping 6/24/03, 5/3/99 and 4/26/91 in SARS on the same sounding? Not bad.

Tuesday next week is looking like a pretty legit threat at this point for somewhere in the Plains. Seeing some pretty top-tier instability/moisture values for late April, which makes sense with that lead shortwave this weekend assisting with poleward moisture transport. Oddly, it's falling directly on the 25th anniversary of 4/26/91.

The 12z EPS looked pretty substantial to me, especially in the 7-10 day period, as did the 12z Euro op. The trough at 192-216 hrs would likely have a more significant potential since that lead wave helps advect mid 60s dews into the Plains (sacrificial lamb more or less). Then there's also that fact that it looks to reload right behind that.

Well that's an interesting #1 analog (some other big periods there too especially in the Plains)...

Things seem to be shaping up for a more favorable look later next week into the following one with multi-model/ensemble consensus of a western trough (and currently a rather progressive regime) setting up shop. Would have to think there would be one or more setups in the Plains if that ends up coming to pass, perhaps even on the more robust end assuming seasonable moisture return (which doesn't look to be out of the question). Not a huge fan of the Hudson Bay troughing that persists, but otherwise things are certainly looking more active for the tail-end of April.

*sigh*

Not sure I've ever seen a signal this strong from the CFSv2 SCP chart for 3 days in a row...especially this early in the season. Pulled a sounding off the 12z Euro at SGF at 180s and it was pretty incredible. Very steep mid level lapse rates (SBCAPE near 2000 J/kg) with SRH in excess of 650 m2/s2 and just a huge sickle shaped hodograph. Hopefully we get some more agreement among guidance for this period in the coming days, because it looks like it could shape up to be a more significant event assuming even rather marginal moisture return (given the impressive thermodynamics aloft).

Figured I'd bump this to let everyone know that the gaps in the ABC 33/40 coverage (on John Brown's Youtube page) of this event are going be filled in over the coming days since Bill Castle found it. The morning coverage (of the intense QLCS that swept through the state) between 3:30 and 6:00 AM is already uploaded. https://www.youtube.com/watch?v=SGqjHgLzibY https://www.youtube.com/watch?v=aZ9S0rFhRHw

Euro + EPS + Euro parallel (and the UK now that it has gotten in range) have been consistently hitting this potential for several days now. A lead shortwave trough ejection and strong lee cyclogenesis looks to occur March 7th (Monday) leading to a strong southerly LLJ of 40-50+ kts encouraging BL dewpoints to rise into the lower 60s across OK and KS ahead of a very sharp dryline. While this moisture may seem rather meager, keep in mind we're also looking at EML-assisted mid level lapse rates of 7.5-8+ C/km with this event, so that should be enough for moderate destabilization assuming some decent insolation (may need to watch for moisture mixing if it turns out to not be overly deep). This will also lead to a rapidly moistening BL further south for the next day. On day 2, the primary upper impulse looks to eject towards the Rio Grande Valley as the low level jet strengthens in excess of 55 kts across E TX, the Arklatex and LA. While the flow does appear to be a bit meridional, there is certainly enough of an upper level jet component ejecting ahead of the trough to encourage storm development out ahead within a potentially very unstable warm sector (strong low level shear as well with backed SSE/SE surface winds underneath the aforementioned LLJ). If this setup turned out to be just a bit less amplified and/or meridional, we'd be talking some serious potential given the amount of instability that looks like it could be present (still think there is quite a bit of potential how it sits now). We'll see what happens as it is still a week out. Definitely looks like the first more significant threat may be on the way with more possible afterwards given GWO progression through at least phases 8-1 and a shift towards a +EPO (Gulf of Alaska trough) through the first two weeks of March. CFSv2 chiclet chart has been lighting up March for the better part of a month now, so this definitely seems to have some legs. Quite a contrast to the past 3 Marches.

If I were a chaser/living in OK/KS/N TX, I'd be keeping an eye on next Monday with the Euro's idea of a strong lee cyclone developing in response to that negatively tilted shortwave trough ejection. Healthy EML overspreads the dryline leading to a pretty wide axis of moderate destabilization along with great directional shear in the lowest 3 km (12z run via 180 hrs).

https://twitter.com/antmasiello/status/698172872704028672 Brilliant,

Bug report: I think the SCP algorithm on the site needs a tweak.

This looks to be what most recent guidance has suggested.

Continued strong signal from the EPS and GEFS for a large western trough developing later next week, thanks to a very impressive jet over the Pacific and a lack of a blocking ridge along the W Coast. Favorable teleconnections with troughing in the Gulf of Alaska (+EPO and -PNA) look to be in place to get this moving into the CONUS. Wouldn't be surprised if 2015 has at least one last go of it in the severe department should this end up verifying, especially considering the location of the SE ridge axis out ahead and what may be quite a moist warm sector (especially by December's standards) by the time the upper level jet pushes eastward of the Rockies. Deep moisture trajectories on the Euro look pretty prototypical for what you would want to see in a cold season event, coming right through the Caribbean. Then it comes down to what character the trough ejection assumes, and whether it will be sheared out if the ridge amplifies too much ahead of it, or whether it amplifies too much and becomes too meridional. This is of course barring any complications from the active southern stream, i.e. shortwaves disrupting the return flow. The more reliable Euro has not been showing this to the extent that the NA models have though, thus has more instability. Regardless, as usual this time of year, the biggest question is always moisture quality and from what I'm seeing, this system does have a reasonably good chance of achieving that. With a very potent jet like this moving onto the W Coast, that is definitely an eyebrow raiser.

HGX had quite the discussion for Mon/Tues in their most recent AFD.

FWIW, the message I'm getting from basically every AFD I've read (OAX, EAX, TOP, LSX, SGF, ILX, DMX, etc.) is concern for just how dynamically impressive this system is, as I've stressed from the beginning with this thing. Troughs like this can and often do pull a lot out of very little thermodynamic wise. Then you start concerning with areas that actually have appreciable buoyancy like closer to the 500 mb low. I also noticed that the Euro was showing some better 700-500 mb lapse rates further south on Wed, although still very little CAPE.

I wouldn't be surprised if this thing peaks severe wise on Wed from 12-18z over the E Plains and Lower MO Valley. Both the Euro and GFS are showing some appreciable instability there closer to the triple point where colder 500 mb temps will result in steeper mid level lapse rates on the nose of the LLJ.

Instability looks rather low, what was once looking like a solid warm sector has shrunk into almost nothing.

This was changed upon further survey. Several homes that were bolted down to their foundations were swept away and these received an EF5 rating. Briarwood was discovered to have had multiple construction flaws and was downgraded.

Lol 2015, like friggin clockwork.

Expecting a 2013-like fall any year would be a tall order, considering that year had not one but two really significant severe events (10/4 and 11/17). However, I would lean more on the active side this fall given that previous ones heading into Ninos have featured some substantial fireworks and especially if this new regime that has taken over the E Pacific continues deeper into October/November (i.e. Gulf of Alaska/western N. America trough).

The EF5 rating was at least partly based (haven't read the survey in awhile) on manhole covers that were thrown from their locations and also concrete parking stops.