u/Key_Hedgehog1664

...Friday/Day 4 to Sunday/Day 6... An upper-level trough will move eastward from the eastern Pacific on Friday into the western U.S. on Saturday, as southwest mid-level flow gradually strengthens over the south-central states. In response, low-level moisture advection will continue over the Great Plains. Ahead of the western U.S. trough, a subtle shortwave trough is forecast to move into the southern High Plains Saturday afternoon. A severe threat will be possible ahead of and near the trough during the afternoon and evening.

On Sunday, the western U.S. upper-level trough is forecast to move quickly east-northeastward into the southern Rockies. Ahead of the trough, a moist and moderately unstable airmass is forecast over much of the southern and central Plains by afternoon. Scattered thunderstorms appear likely to develop over much of this airmass during the afternoon and evening. Moderate to strong deep-layer shear appear likely to be in place, which will be favorable for severe storms. Supercells with large hail, severe wind gusts and a tornado threat will be possible. An isolated severe threat may also develop in parts of the north-central U.S.

...Monday/Day 7 and Tuesday/Day 8... A secondary upper-level trough is forecast to move into the Desert Southwest on Monday. Ahead of this system, a moist and unstable airmass is forecast to remain in place from the southern Plains north-northeastward into the Upper Midwest. Although a severe threat will be possible along much of the instability corridor, the greatest threat is expected to develop in the southern Plains, where model forecasts show the most favorable environment.

On Tuesday, model forecasts have some agreement concerning the timing of the trough, which is forecast to eject northeastward across the southern and central Plains. Ahead of the trough, there is large variance among the models concerning the distribution of instability. If a moderately unstable airmass is in place by Tuesday afternoon ahead of the ejecting system, a severe threat will be likely from the southern Plains into the mid to upper Mississippi Valley. However, the system will probably be slower than forecast, which adds considerable uncertainty this late in the period.

...Saturday/Day 6... On Saturday, the potential for severe storms is expected to increase over parts of southern High Plains, as mid-level southwesterly flow strengthens. Model consensus suggests that the greatest severe threat potential will be over parts of west Texas, where some models have an axis of moderate instability in place by late Saturday afternoon. Supercells with large hail and severe wind gusts will be possible in the afternoon and evening, with storms that develop near this instability axis.

...Sunday/Day 7 and Monday/Day 8... On Sunday, an upper-level low and an associated trough is forecast to move eastward across the Desert Southwest and northern Mexico. Ahead of this trough, moderate instability is forecast to develop by Sunday afternoon over much of the southern High Plains. Scattered severe storms would be possible to the east of a west Texas dryline in the afternoon and evening. A severe threat should continue into the overnight as a low-level jet strengthens ahead of the approaching trough.

On Monday, the upper-level trough is forecast to move quickly northeastward across the central U.S, with an axis of moisture and instability located in the Great Plains. Scattered severe storms will be possible from Monday into Monday night from the southern Plains northward into Upper Midwest. At this extended range, there is still considerable uncertainty concerning the timing of the trough. For this reason, will hold off on a threat area until the models show better agreement.