Scattered severe thunderstorms are forecast for Wednesday into Wednesday evening across the Southern Great Plains, particularly from the Texas Panhandle to southeast Kansas. Hail and damaging winds are the main threats, with a very low tornado risk also apparent across portions of Oklahoma.

Locations:

  • Slight Risk Area: Texas Panhandle to southeast Kansas.

Threats:

  • Large Hail: Transient supercells and clusters capable of producing large hail are expected.
  • Severe Wind Gusts: Severe wind gusts are also likely with the stronger storm clusters.
  • Tornadoes: A tornado or two cannot be ruled out, but the risk is very low.

Timing:

  • Storm Development: Late afternoon and evening hours are likely to see the initiation of severe thunderstorms.
  • Decreasing Threat Overnight: Severe threats are expected to wane as the night progresses.

Meteorology Breakdown:

  • Synoptic Setup: A series of lower-amplitude shortwave impulses will be moving east across parts of the Upper Midwest to the Southwest states. Additionally, a shortwave trough moving from the Ohio Valley to the Deep South will exit off the South Atlantic coast early Thursday.
  • Surface Features: A generally north/south-oriented cold front extending south from a weak surface cyclone over eastern South Dakota will be a focal point for thunderstorm development. Secondary cyclogenesis is expected just offshore of the Virginia/North Carolina coast.
  • Thermodynamic Environment: In Oklahoma and southern Kansas, low 60s boundary-layer dewpoints will advance north from East Texas, contributing to a moderately unstable airmass with MLCAPE values between 1500 and 2500 J/kg by peak heating. Further north, weaker buoyancy suggests a more marginal severe threat in the Mid-Missouri Valley.
  • Dynamics and Shear: Low-level convergence along the front and dryline, post-frontal upslope flow near the Raton Mesa, and a strengthening low-level jet from West Texas towards southeast Kansas/northeast Oklahoma will support scattered to widespread convective development by Wednesday evening. The shear profiles, while modest, will be sufficient to support organized storm structures, including transient supercells.

Technical Discussion:

Refcmp uh001h.us sc-29.

Tomorrow’s storm mode looks mixed, with the possibility of a supercell or two across Oklahoma. Further south and west, the low-level environment looks drier on most models, which results in a near-instantaneous evolution into a weak squall line with a large trailing precip shield. Another area to watch for possible supercell development is off of the Raton Mesa in NE New Mexico and the NW Panhandles.

Hrrr_2024051412_036_area_35.52 36.14. 97.77  96.94.

I’m intrigued by the Oklahoma target, which has 0-6km shear at nearly 30 knots with MLCAPE at 2500+ j/kg. This environment could result in a right-turning supercell that is conditionally capable of all hazards as it slides east/southeast very slowly. The caveats to this are crowded storm modes are more likely, and a storm would take a bit to get going in this environment. Still, I don’t want to rule out this happening with a tornado being possible.

Rrfs a 2024051412 033 36.62--103.32.

The other area I’m watching for potential supercell evolution (or at least pretty storm evolution) might be NE New Mexico and the NW Panhandles. At first glance, this sounding does not look that great. But the 40kts of shear with storms coming off the mesa with lower DCAPE values may signal you could keep a cellular (but dry) storm mode for a bit as storms move east and south. I don’t think this is likely, and I would classify it as a very low probability, but I’ve seen that region do some wild things in conditions you wouldn’t otherwise expect them.