Delivery of chilled air to the Bethesda station has been temporarily disrupted. Contractors are on scene diagnosing the problem. 

Background
Metro's underground stations are cooled by chilled water air handling units, or "chillers," not air conditioning. The chiller system is designed to reduce temperatures in stations for rider comfort. The hotter the outside air, the less the chillers will be able to do. By design, if the ambient outdoor temperature is 91 degrees, the chillers will bring the station temperature to 85 degrees.

We have ensured the tunnel and station ventilation fans are active at Bethesda to provide passenger comfort; however, even with these efforts, the station will seem warmer than usual until repairs are completed. We apologize for this inconvenience and thank you for your patience.