NWS: Shiawassee County under severe thunderstorm watch until 7 p.m.

The National Weather Service in Detroit/Pontiac put Shiawassee County under a severe thunderstorm watch at 2 p.m. Thursday. It runs until 7 p.m.

The watch — numbered 648 — covers 15 counties across southeast Michigan, from Bay and Saginaw down through Genesee, Livingston, Washtenaw and Wayne. The weather service listed Owosso and Durand among the cities inside the watch area, along with Flint, Lapeer, Fowlerville and Saginaw.

A watch is not a warning. It means the weather service considers conditions favorable for severe thunderstorms to develop in the area over the next several hours; a warning means one has actually been spotted or picked up on radar. The alert lists the response as "monitor," and the weather service put the certainty at "possible."

This is the county's second round of storm alerts Thursday. The Current reported this morning that the weather service tracked a strong thunderstorm near Laingsburg at 9:59 a.m., moving east at 35 mph toward Perry, Corunna, Owosso, Durand and Byron, with gusts to 50 mph and nickel-size hail possible. We still do not know whether that line brought down trees or knocked out power anywhere in the county, and the weather service has not published a damage summary.

The 2 p.m. product does not spell out what hazards forecasters expect this afternoon — no wind speed or hail size is given in the watch text, and no instruction paragraph was attached. That detail typically comes with any individual warning issued inside the watch.

If you have outdoor plans between now and 7 p.m., the practical read is to keep a way to get alerts with you. Several county high schools have games and practices in that window.

What happens next: The watch expires at 7 p.m. Thursday unless the weather service cancels it early or replaces it. Any storm that actually develops would come with its own severe thunderstorm warning naming specific towns and a specific arrival time. The Current is watching for warnings, for damage reports and for answers on this morning's storm.