12AM Day 2 Convective Outlook for Saturday, October 11. THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE INTERMOUNTAIN WEST .
SUMMARY
Thunderstorms with marginally severe wind gusts and hail will be possible on Saturday across parts of the Intermountain West.
Intermountain West
At mid-levels, a trough will move into California from the eastern Pacific on Saturday, as southwesterly flow remains over much of the Intermountain West. Mid-level heights will fall across much of the region as the trough approaches during the day. At the surface, a Pacific cold front will advance southeastward across south-central Nevada and southern California. A moist axis will be in place early in the day across eastern Nevada, but this feature will shift eastward by afternoon. Along and near the moist axis, instability will develop as surface temperatures warm. Scattered thunderstorms appear likely to form in the afternoon from Utah into Arizona and eastward to the Four Corners vicinity. RAP forecast soundings in the mid to late afternoon ahead of the front across central Utah and northern Arizona have MLCAPE around 500 J/kg, with 0-3 km lapse rates around 8 C/km. In addition, moderate deep-layer shear is forecast. This environment should be enough for an isolated severe threat. The stronger storms may be capable of marginally severe wind gusts and hail. The threat could persist into the early evening, in areas that destabilize the most.