Plenty can change at this range, and model uncertainty will remain elevated for a while. That being said, some of the models are definitely suggestive of what would (in my opinion) be a pretty significant severe weather and tornado event on Monday.
Trough ejection looks already pretty favorable... long branch of strong mid-level flow, with a quick moving shortwave translating NE into the Upper Plains/Midwest region during the afternoon and evening of the 28th. Quick trough ejections should already raise some alarm bells (with reference to Chris Broyle's Omega Project). Not only that, but the majority of models have very rich moisture, strong lapse rates, which results in very robust instability profiles.
Most guidance suggests a strong LLJ will develop 21z-03z and I think wind shear will be more than sufficient for supercells.
Model differences exist in the parameter space and trough ejection, though all models depict environments at least somewhat favorable for severe weather/tornadoes.
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ICON and UKMET soundings posted above. I can understand why some may be concerned about a seeming lack of wind shear, which is fair enough given all our major events this year were earlier in the season and driven by super impressive kinematics. But in this case, 200-300 effective SRH is more than enough for EF2-3+ tornadoes, in my opinion. Not only is the hodograph shape itself consistent with higher-end tornado events in the past (sickle shape can be very efficient at producing tornadoes, even for technically lower shear values) but the instability is making up for it. If I'm completely honest, were the ICON to verify, I think we would see a major tornado outbreak.
All of that is said, of course, with the usual caveat with mid-range severe weather setups. Everything is subject to change, and mesoscale details which can make or break a setup may not be apparent until a few hours before! But at least at this stage, I am worried for the Plains and Midwest on Monday.
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