This evening, isolated severe thunderstorms are expected across west central Texas, capable of producing large hail and damaging winds.

Locations:

  • West Central Texas: Specific focus on areas along the developing dryline.

Threats:

  • Large Hail: Isolated very large hail up to 2.5 inches in diameter.
  • Damaging Winds: Severe outflow gusts ranging from 60-70 mph.
  • Tornadoes: An isolated tornado is possible during a narrow time window this evening.

Timing:

  • Peak Activity: Late afternoon to evening as surface heating potentially erodes convective inhibition.

Discussion:

  • Weather Patterns: A midlevel shortwave trough moving inland over southern Arizona will influence weather conditions downstream. Shortwave ridging over the Plains and increased westerly flow over the Rockies will enhance lee troughing across eastern Colorado and New Mexico.
  • Atmospheric Dynamics:
    • Surface and Moisture: The lee trough will support sustained southerly low-level flow, increasing moisture under a warm elevated mixed layer. Midlevel lapse rates between 8-9 C/km will promote significant buoyancy (MLCAPE > 2000 J/kg), despite a capped warm sector.
    • Storm Development: Along the dryline in west central Texas, deep surface heating could reduce convective inhibition sufficiently to allow isolated thunderstorm development by this afternoon or evening.
  • Severe Potential: The environmental setup with large buoyancy, steep lapse rates, and effective bulk shear over 40 kt is conducive for supercell formation, which can produce very large hail and severe gusts.
  • Practical Tips:
  • Target Area: Focus is near the dryline where heating and moisture are optimal for convective activity.

Impact: The combination of high instability, effective shear, and sufficient moisture increases the potential for severe weather events in west central Texas this evening.

Technical Breakdown

A small and compact wave, well sampled by the morning run of the HRRR, will move east over the dryline by late afternoon and early evening. Storm formation is not certain, but it would be in a narrow area south of Amarillo to I-20 in West Texas.
If there are storms tonight, expect only a couple. Still, this is an idealized storm chasing setup with the potential for a very photogenic storm present this evening.
Forecast soundings show a near-idealized hodograph shape for incredible storm structure; this occurs across multiple models but isn’t entirely consistent. As far as the tornado risk, it is not zero, but low amounts of 3CAPE and high cloud bases due to dry low levels will limit the overall threat. A robust supercell just after sunset may make it happen even still. The threat of that is low, with the bigger concern being large hail.
One of the things that will work against getting a storm today will be the diffuse nature of the dryline throughout much of the day. Surface convergence isn’t as strong as many. Models keep the dryline as more of a moisture gradient throughout the day. Still, localized terrain enhancements across the Panhandle and South Plains, with an upslope-like effect, will possibly be enough to get a few storms going if the wave can make it in time.