Outlook for ArkLaTex Through Portions of the Lower Ohio Valley:
A limited but notable setup primarily for large hail and damaging winds is anticipated across the ArkLaTex Region through the lower Ohio Valley later this evening through the overnight hours pushing eastward. These storms will develop similarly to a summer setup although later in the d day, becoming severe quickly, with large hail as the main risk given the conditions. After merging, they will primarily pose a damaging wind threat overnight. For more details on the forecast, please check below.
Main impact: large hail, damaging winds, very low risk for an isolated tornado, and CG lightning.
Approximate Timing: Expected to form around the late evening mainly pushing north eastward through the impacted regions into the overnight hours and early morning hours of Saturday.
Overall Forecast: In the mid/upper levels of the atmosphere, a southwesterly mid/high-level flow, combined with a shortwave trough over the south-central High Plains, will continue northeastward as it slowly weakens. At the surface, a boundary will sweep across the region, bringing somewhat elevated warm air advection ahead of it. Dew points are anticipated to reach the low 60s across the impacted regions. This, combined with somewhat elevated instability (CAPE values mainly in the mid to upper hundreds) and elevated effective shear, will enable the formation of some storms in the ArkLaTex area and across Arkansas. The main risks from these storms include large hail and potentially damaging winds, especially given the downward instability values mainly in the late evening through the overnight hours. Due to the lack of low-level shear, the risk for isolated tornadoes will be very low, so the primary concerns with these cells will be large hail and damaging winds.