UPDATE FOR WEDNESDAY:
IF YOU ARE GOING TO THE FIREWORKS

It could be stormy fom the clouds not from the River

From the Official web page of culture city:
The Local 4casters[WDIV-TV/NBC 4]

Wednesday:

mostly cloudy with scattered showers and thunderstorms.
Highs 85 to 89.
Chance of rain 40 percent.

Wednesday Night:
[Firework show to beging at 10:06 P.M.]

mostly cloudy with scattered showers and thunderstorms.
Lows 63 to 67.
Chance of rain 40 percent.

Thursday:

partly sunny with a slight chance of showers and thunderstorms.
Highs 78 to 82.
Chance of rain 20 percent.

Thursday Night:

partly cloudy.
Lows 55 to 59
[So if Wednesday Night dont work out, Thrusday night would be perfit.]