re: Tornado! - Bassfield, MS rated EF-4 w/ 63 Mile Track, Peak Winds 170 mph

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East TX northeastward through much of the Southeast and TN Valley... One or more clusters of deep convection will likely be ongoing at 12Z Sunday morning somewhere over east TX and potentially into portions of the lower MS Valley. The intensity and areal extent of any such clusters remain uncertain, but ample shear and instability will favor a threat of hail and damaging wind with any organized convection at the start of the period. Some tornado threat will also be present Sunday morning with any semi-discrete storms that begin to interact with the richer low-level moisture in the vicinity of the warm front. As this convection spreads northeastward, intensification is possible into portions of the ArkLAMiss region, with an increasing tornado threat in late morning/early afternoon with any surface-based storms, given rapidly increasing low-level moisture and shear. North of the warm front, evolution into a QLCS will be possible, with a corresponding risk of damaging wind into portions of the TN Valley.

Meanwhile, further south, moderate to locally strong instability is forecast to develop along/south of the warm frontal position, which will be modulated by the impact of outflow from any early convection described above. Midlevel flow will increase to 70-100 kt as a south-southwesterly low-level jet intensifies into the 40-60 kt range. These wind profiles combined with ample instability (MLCAPE of 1500-3000 J/kg) will support the potential for intense supercells. Any surface-based initiation along and east of a pseudo-dryline moving into western LA by late afternoon could evolve into one or more long-tracked supercells capable of producing strong tornadoes, large hail, and damaging wind gusts. The extent of development within the warm sector remains somewhat uncertain, given the presence of a capping inversion and generally subtle foci for initiation. While the conditional risk of all severe hazards will be quite high if supercells develop, uncertainty remains regarding how convection will evolve from the morning into the afternoon. Any remnant outflow related to early convection will determine the northern extent of the higher-end tornado potential, and some guidance suggests the potential for elevated convection within a midlevel moist plume across the warm sector during the afternoon, which could either dampen the severe potential, or evolve into surface-based convection with a substantial severe threat. Given these factors, there is too much uncertainty to upgrade the ongoing outlook at this time.

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there is too much uncertainty to upgrade the ongoing outlook at this time.

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some guidance suggests the potential for elevated convection within a midlevel moist plume across the warm sector during the afternoon, which could either dampen the severe potential, or evolve into surface-based convection with a substantial severe threat.

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It looks like a lot of the hi-res models like the solution of multiple rounds of elevated storm clusters before the Pacific front over takes things and everything lines out.

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I've seen a few people suggest that they don't think hi-res models/CAMs are handling the setup well, and that junk convection will be more limited that what they are currently suggesting. I don't know what to think

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When was it? Last year? when there was this major tornado outbreak forecast that ended up being much less than expected?

Then, about a month later storms brewed up were worse than what occurred on the "bad" forecast day.

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Watch storms across Texas later today to see if they develop into a complex that maintains overnight bringing rain into the warm sector tomorrow morning.

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