Clouds, a few rain showers and cool temperatures are forecast for the Star-Spangled Spectacular festivities around Baltimore into this weekend.
The celebrations are expected to start with some humid and possibly stormy weather. Uncomfortably humid air, cloudy skies and likely storms are forecast Thursday, the first day visiting tall ships will be open for tours.
A 60 percent chance of storms is expected Thursday afternoon and evening. About a quarter of an inch of rain is possible, and some storms could be severe.
A coastal flood advisory is meanwhile in effect along the western shore of the Chesapeake Bay, including in Baltimore and Annapolis, with high tides up to a foot and a half above normal.
More pleasant weather is expected for festival villages in the Inner Harbor and at Fort McHenry that will be open Friday through Sunday, for Blue Angels air shows Saturday and Sunday, and for a nationally televised concert and massive fireworks show Saturday night. But some rain showers are possible for much of Saturday.
A cold front that could prompt the Thursday storms will bring unseasonably cool temperatures, with highs in the mid-70s on Friday and perhaps only about 70 degrees Saturday and Sunday. Weekend overnight lows could reach the mid-50s downtown and lower 50s or upper 40s further outside the city.
A 50 percent chance of showers is expected for most of Saturday. They could extend into the scheduled 9:30 p.m. fireworks show. Less than half an inch of rain is expected throughout the day.
Long Island-based Fireworks by Grucci will use proprietary pyrotechnics in what it calls a "world-class" show, etching stars and stripes into the sky and emulating the rockets' red glare of the Battle of Baltimore 200 years ago.
Partly cloudy skies are forecast Sunday for continuing events downtown and at the Inner Harbor, and for the Hampstead Hill Festival at Patterson Park.