Why the NFL rejected the 49ers' request to switch to white jerseys against the Cardinals as a heat wave hits the Bay Area

It may be the first game of October for the San Francisco 49ers on Sunday, but this Week 5 game against the Arizona Cardinals will be anything but a fall feel. With a heat wave hitting the Santa Clara area, the Niners hoped to make a last-minute change to their uniforms for this game to better withstand the weather.

Head coach Kyle Shanahan told reporters Friday that the team has petitioned the NFL to switch from the usual red home jerseys to white because that color would absorb the sun's rays less. However, the league refused. The Cardinals will wear their white jerseys on Sunday.

“We asked on Monday, but we weren’t allowed,” Shanahan said, via 49ers Webzone. “You had to [request] it before the start of the season. In order for us to do that, we have to sort of make a conscious decision or commitment before the year to wear all white until about mid-October or whatever and then go back to normal. But it's not usually that hot, so we'll probably do that now just in case.

It looks like the team will opt to simply don their white jerseys at the start of the year to avoid a situation like this in the future. While the league vetoed the 49ers' request to wear these white jerseys, they were able to switch to their retro jerseys, which feature the red jerseys but white pants instead of the gold.

“Yeah, they let us do our throwbacks, just alternate it with others so we get as much white as possible,” Shanahan said. “And the best we can do is white pants, so hopefully that helps a little.”

According to the National Weather Service, an excessive heat warning is currently in effect around Levi's Stadium and is scheduled to remain in effect until 11:00 p.m. PT Saturday.