Widespread Severe Weather Returns to the Plains

An early Summer severe weather outbreak looks to be taking aim at the central plains this weekend into early next week. Severe storms capable of damaging wind and hail, and perhaps a low-end tornado threat although high-based, elevated storms should temper the overall tornado risk, are expected across portions of Oklahoma and Texas eastward. The "peak" of activity appears to be tomorrow (Sunday 24 June) however. A more significant scenario has the potential to unfold across most of Kansas into the Oklahoma/Texas panhandke region. All hazards are possible tomorrow as initial supercells will be capable of tornadoes, large hail, and damaging wind. Through the evening, an intense MCS is expected and extreme wind gusts as well as embedded mesovortices will be possible. A flood threat may develop too if storms end up backbuilding.
From our perspective as chasers we're considering two possible target areas. Target #1 is the sfc-low/triple-point in Southwest KS to the OK panhandle. Target #2 is near Hays, KS along I70.
I'm leaning toward the triple-point play because, for one it's the triple-point, a classic target for us. Also, I feel fairly confident that storms will be more discrete here and the environment should support strong supercellular storms. I'm thinking the cap will break across the panhandle by 21-23z (4-6pm) and this would put us in the vicinity of the "burst point". I'm also somewhat concerned with early-day convection and a possible upstream cluster moving in from Nebraska with the northern target.

A substantial overlap of ingredients favorable for severe storms is suggested in the vicinity of the triple point in southern KS. The area circled in black is the region I'm targeting for supercells and possibly a few tornadoes. (Note: Significant severe weather is possible outside the circled area, that is just the region we are targeting)

Either way, significant storms are expected across the region Sunday with both the initial supercells and the eventual powerful QLCS and anyone in the area should monitor multiple sources of weather information and listen to all watches and warnings.

The Setup

So what is coming together for this fairly noteable late-June severe weather? Unlike the diurnally-driven "pulse" storms that are oh so common this time of year, we actually have a relatively strong upper-low/"kicker" swinging around the Rockies. Normally during the Summer we see extreme instability and very rich atmospheric moisture but weak flow aloft owed to the northern retreat of the polar jet results in high CAPE-low shear setups, in other words, a lot of disorganized convection. In this case however, we have a 50kt speed max associated with our mid-level "kicker" that's going to lead to stronger deep-layer shear atop our Summer instability. Steep lapse rates overlapping a very moist & unstable boundary layer with plenty of effective shear sets the stage for more organized severe storms. While not impossible to see this type of setup at all, it's also not the most common thing during late-June.

GOES East water vapor imagery shows an upper-low over Wyoming with an embedded shortwave trough pivoting around it. This shortwave will eject over the central plains tomorrow with a 50kts speed max overspreading the KS/OK/NE region. Surface cyclogenesis will occur and surface-low will deepen and lift northward, bringing a frontal boundary with it. 

A "theta-e" axis associated with out moist sector will be established across the target area providing plenty of "juice" to work with. 

A plume of very steep lapse rates atop a very moist boundary-layer will aid in strong instability developing tomorrow afternoon. Effective wind shear of 40kts and backed surface winds, especially along the boundary, may support supercells and decent curvature of low-level hodos suggests tornadoes are possible. Low-level thermodynamics also seen seem to support the stretching of low-level circulations to the ground, should they develop. 

Storm-relative helicity values support rotating updrafts, particularly after 0z (7pm) when the low-level jet gets cranking. 

There are uncertainties regarding the exact evolution of tonight's convection as well as location of outflow boundaries tomorrow. The NAM has also been a well-noted consistent outlier. We'll tighten up the details tonight and in the morning at the hotel so stay tuned for that. It looks like a busy day tomorrow though. Severe chances, though not as substantial as Sunday, will continue through Tuesday and I'll have chase forecasts for those days as well following tomorrow's chase. See ya soon!