bjc0303

Agreed. It's a shame this Atlantic system had to blast a cold front into the Gulf. The second that happened, this one was pretty much dead. Strong moisture return on the heels of a frontal intrusion will always throw us under thick cloud cover, and that concerned me from the start. Given I live in OK, this one is still probably worth watching, especially morning of.. But I wouldn't exactly say I'm holding my breath on it.

Warmest temps are always behind the dry line.. The thermal axis should lie along and behind the dry line during max heating.

I don't see the moisture being the problem as much as cloud cover inhibiting insolation (on the GFS at least). And this isn't overturning, either. With recent frontal intrusions comes airmass modification, and with isentropic upglide happening we can probably expect tons of cloud cover, at least early on. Guessing that's why the GFS isn't getting surface temps too high. ECMWF on the other hand puts out low 70s over a broader region. Find a sounding (on the GFS) with low 70s temperature and the inhibition is nearly gone even with upper 50s dewpoints. Not really time to get caught up in EML temperatures. The strength of the wave itself will provide some pretty impressive ascent. We'll see how much of that glances the southern portion of the dry line however.

Looks as if the 12z ECMWF has taken a step towards GFS with wave amplification, leading to a stronger anticyclone..at least by Sun 12z. Still loading in. And none of this will really change how much snow is seen..the broader large scale pattern will keep heavier snowfall from being a thing. We need some deep system out of the southwest, at least for those of us in OK/TX/KS..

Keep in mind, these really cold patterns are usually the result of highly amplified ridges with a NE trough.. While the pattern is great for repeated shots of cold air masses, it is not-so-good for moisture return nor is it going to result in a storm track conducive for widespread plains snowfall. Until we get out of this N/NW flow aloft we will stay cold (sometimes bitterly cold, like is being hinted at next week) but relatively dry.

Should note that shear values (specifically, low level shear (strong SRW and SRH) abs deep layer (effective bulk shear) are far more important than the 500 mb flow values. Hence why OFBs are important in late season tornado events. They don't alter the flow aloft, but alter low level flow increasing low- and deep-layer shear... while also providing a rich source of low level horizontal, streamwise vorticity owing to barpclinic zone (often leading to accelerated low level mesocyclogenesis). You can have 55 knot 500 westerly flow, but it won't mean much with 45 knot surface westerlies... odd example, unrealistic even, but the point remains. Shear, and SRW, dominate over the pure mid level flow. Would be interested though in examining borderline cases where low level shear is high (ESRH greater than, say, 250?) But deep layer (effective BWD) fails to meet 35 knots.

Yeah, I'm really hoping for some KS/NE/IA action. I really don't want to have to drive way up to the Dakotas.

It's been brutal, this pattern. Making it worse is the persistence. They say persistence pays off..... Hopefully that applies to meteorology!

Yeah, just gonna have to make due (Fri/Sat) with what we have. Still not buying Friday staying completely capped, and will eagerly await coming home with a burn/tan if it does fail to convect. I agree though, what a waste of TWO pretty severe-favorable looking longwave troughs. One in late April and the other last week. Unbelievable that neither quite panned out.. Both had outbreak potential, relatively speaking (as happens with pronounced, favorably-positioned longwave patterns). I wouldn't give up on June quite yet (although, if you're stuck with southern plains chasing, perhaps).. Central and northern plains through June could be rocking.

Agreed. Synoptically driven patterns don't look completely dead however. FWIW (very, very little) the 06z GFS shows an active pattern into June.. Which would likely bring a string of active days over KS, NE, perhaps even OK (pending EML strength). Jet certainly looks to remain active for at least another 2-3 weeks; this is reflected in the recent ERTAF forecast.

Pretty good signal, tho think GFS probably a hair too east as usual putting OKC/Norman in risk area. Think we will get a quality two days of storms, 2013 style with a dry line/sagging cold/stationary front.

Looking more and more like tornado activity will pick back up again late this week into the weekend. Models now converging on what I would call a typical late may tornado setup with rich gulf moisture, strong-extreme instability, and a well developed evening LLJ. More fine-scale details cannot be resolved right now, such as strength of the EML/base temps, boundary placement, etc.. but looking increasingly conducive for tornadic supercells. Unlike recent setups this one may have more densely populated areas in the mix. Not worth going over much more at this point. GFS forecasts have quite the hot EML, but no real consistency. While some parts may get shut out due to capping, someone is going to see CI. Even now the GFS convects, and I imagine smaller scale perturbations provide glancing influence to erode capping. Saturday may be an outflow boundary day.

Disagree on capping. If anything, 1) morning convection and 2) high LCL heights may be an issue, but given we are five days out, it is hard to put much stock into analyzing anything more than the large scale pattern. 12z ECMWF edit: early precip looks to be less of an issue Tues this run. Again - kind of pointless analyzing details like this, but the ECMWF lights up a large portion of the OK/TX/KS dry line with QPF 18-06z Tues. Does so again Thursday... Will have to watch.

While details get washed out in the mean, I really can't complain about this sequence throughout the week. impressive. Considering various deterministic and ensemble solutions... Tues, Weds, and Fri look interesting to me. Weds is conditional on timing, where Tuesday looks more certain. Friday looks solid on the large scale. we'll see how things pan out but I really like the prospects of next week.

Gotta say that ensemble mean forecasts for next week look pretty impressive, with promising events possible Tues, Weds, and Friday it looks.

EPS mean shows a pretty prolonged period of western troughing

Latest deterministic and ensemble models show.... next to nothing for the entirety of the cycle. EPS offers a *glimmer* of hope at the 330-360 hour range... But it's looking pretty meh across the board.

That and trough activity over NE

I think there's some huge differences between this Friday's trough and next week's. The two manifest themselves in different ways. This one more progressive, meaning less room for error. Next week's trough is a large-scale trough with shortwaves moving with the mean flow. These are where your outbreaks come from. Not to say next week will be an outbreak - so much can go wrong with severe. However, I don't think the two are very comparable.

To sum up the EPS and ECMWF for the medium/extended range.... Bigly

Just waiting for the GPS to trend to the euro at this point... but the GFS has been very consistent as has its ensemble

Would think the euro caves. GFS has been *very* consistent. On the GFS.. this would favor discrete tornadic supercells by as early as 21-22z. Rapid storm organization would be likely with ample low-deep layer shear early on in the day. Could be a busy day if the GFS verifies.

It is encouraging to see EPS/GEFS show mean western troughing through the end of month and early May..essentially the second half of fcst period is mean troughing to our west.

Operational runs don't offer much of a clue as to whether it's going to be active or not. Operational GFS could never show those troughs again. What should be a welcome sight, however, is this: This lends credence to the GFS, and the GEFS/EPS seem to be in very good agreement on that period being particularly active. Also fits the recurring pattern of active end of month into early month. GWO/AAM forecasts also indicate increased svr potential in that time frame. Do we get a bigly stretch? Tough to say obviously, but keep in mind that an active period in late April into early May can prove bad, given favorable interactions of the still-active jet with dewpoints beginning to commonly approach upper 60s and low 70s...

Unless the 00z ECMWF is strongly different from the 00z GFS, I'd expect at least a 15% contour added for Fri. GEFS and now operational GFS has trended to a more substantial shortwave given weakening trend on dprog/dt with CAA regime in the wake of initial wave departing, allowing stronger lee-side cyclogenesis to occur as a result. Current progs have a weakly capped atmosphere by 21z with strong shear in place. Storms (verbatim) would probably organize pretty quickly, posing a tornado threat early. Weak low level lapse rates and increasing inhibition by 00z look to be an issue and we'll have to see how far that warm front truly makes it but trends are very encouraging! Will likely be a very strongly sheared environment.