Increased security measures at Walter Reed National Military Medical Center could have a significant impact on local traffic this afternoon, according to Montgomery County’s BRAC coordinator.

Phil Alperson said residents, employees and visitors in the area can expect delays and intermittent road closures from 3:30 p.m. to 5:30 p.m. today.

Across Rockville Pike, NIH has advised its employees to enter and exit on the Old Georgetown Road side of campus “to help alleviate traffic backups” on Rockville Pike.

Base spokesman Joe Macri declined to elaborate on the anticipated delays, saying, “In the interest of force protection, we are unable to discuss specific security measures taken.”

President Barack Obama visited wounded troops on the base on Dec. 20, a pre-holiday closed-to-the-media session that didn’t cause any significant added traffic.