The Storm Prediction Center has placed parts of the forecast area in a “Slight Risk” for severe thunderstorms on Friday afternoon. Although
widespread or organized severe weather is not expected to impact the area, the potential does exist for some isolated to scattered thunderstorms which could be capable of reaching strong/severe levels. The main threats with any of the stronger storms would be heavy rain, frequent lightning, and the potential for some strong wind gusts. The storms are expected to form in the late afternoon and evening, and move east/southeast through the area in advance of a weak cold front and upper level trough. Atmospheric conditions (kinematic and thermodynamic) are supportive of some strong storms thanks to the presence of moderate instability juxtaposed with adequate shear for storm organization. The Storm Prediction Center’s “Slight Risk” on the Day 2 Outlook (for Friday) is triggered by a 15% probability of severe weather within 25 miles of a point.
The instability is being driven by daytime heating in a warm sector, which will move into the area Friday afternoon after a warm front moves through the area Friday morning. However, areas near the coast and east of the city will struggle to gain instability as the marine layer remains in place there. Thunderstorms could still move into these areas, but they likely won’t be severe or as strong as they are farther to the west, where surface based instability is more favorable. Stay tuned for more updates as Friday draws closer — and of course, on Friday, for the new Storm Prediction Center outlook and any severe thunderstorm watches/warnings.