11PM Day 1 Convective Outlook for Wednesday, February 18. NO SEVERE THUNDERSTORM AREAS FORECAST
SUMMARY
Isolated to widely scattered thunderstorms are possible along parts of the West Coast, southern Great Basin, central Rockies, and the lower Great Lakes regions. Severe weather is not anticipated.
Discussion
A series of mid-level troughs will traverse the CONUS Wednesday morning through late Thursday. Across the western US, a trough will gradually shift across the Great Basin with enhanced mid-level flow overspreading the Desert Southwest into the central/southern High Plains. Forcing for ascent and cooling temperatures aloft will bring scattered thunderstorm activity across the central California coast to the Oregon/Washington Coast. Additional thunderstorm development will be possible across the southern Great Basin into the central Rockies. Generally weak thermal profiles will limit severe potential with this activity.
A secondary trough will continue to shift northeast across the Great Lakes Region. Scattered thunderstorm development will be possible along an eastward moving front within a narrow region of warm air advection. Given the generally narrow/weak region of marginal instability, activity is this region is expected to remain sub-severe.