With a 60 percent chance of rain this evening, there was some concern lightning would prevent the show from going forward.
Live Nation released a statement this afternoon, via spokesman Jeremiah Xenakis:
"Fans should wear their raingear. The concert will proceed rain or shine. If due to weather, it is deemed dangerous to the fans, then a decision would be made at that time."
Earlier: what fans are allowed to bring to the stadium.
A source at M&T also said the stadium has an emergency plan for shelter in case of lightning.