All the fireworks set off on or about the 4th of July (in the US, of course) should produce a plethora of nucleation particles for water vapor. So does this actually cause the weather on or just after that date to be especially rainy? Has anyone done a study on it, say comparing the amount of precip on those days with those of other summer days?
We’ve been having a very serious drought in these parts. Last night it began raining and we’ve had showers on and off ever since. How can we get a grant to study this possible advantage of using fireworks. I’ll write the National Fireworks Manufactureres Assoc. and see if they’ll chip in. 
Previous thread regarding the 5th of July.
One time on a trip back to Iowa we got snowed on in Jackson Hole, WY on the 4th of July.