During the dark days of last winter, doubts may have arisen about whether summer would ever come. Tuesday helped to remove those doubts, providing persuasive evidence, in statistics and perspiration, that summer has arrived in Washington.

A heat record was set. Commuter railroads reduced speeds. In the District, trash is being picked up earlier than usual, and spray pools are opening ahead of schedule.

Tuesday was Washington’s third 90-degree day this month and the fifth this year. If the temperature reaches the 90s Wednesday, as expected, it will mark three consecutive 90-degree days.

The high reading at Reagan National Airport on Tuesday set a Washington record for June 17. At 1:41 p.m. the mercury at Washington’s official measuring station reached 97 degrees. That eclipsed by two degrees the previous mark, which was most recently reached in 1991, according to National Weather Service figures.

In a city that knows summer, adjustments began. The District’s Department of Public Works announced that trash collections would start at 6 a.m. through Friday in deference to the forecasts. Throughout the summer, the DPW said that when 90-degree days are forecast, collection crews will start at 6 a.m. to avoid health or environmental problems.

The D.C. Department of Parks and Recreation said it would help the city keep its cool by opening all spray parks a week early, starting Tuesday. Hours of operation are from 10 a.m. to 7 p.m., the department said.

And both the Virginia Railway Express and Maryland Rail Commuter systems said heat restrictions would slow service on sections of their routes for part of the day. The reduced speeds are to protect against possible problems posed by expansion of the rails in high temperatures.