The tarp is on the field at Nationals Park and the weather forecast appears grim.
The Nationals are using their standard lineup against right-hander Jacob Turner.
Denard Span is one game away from tying Ryan Zimmerman's team record 30-game hitting streak.
Denard Span, trying to extend his hitting streak to 29 games, tops a typical Nationals lineup.
The shortstop will play despite nursing hamstring tightness in recent days and the catcher's streak will end at 24 straight games started.
The catcher will start his 24th straight game behind the plate and Davey Johnson will check on him and Desmond after the first game.
Wilson Ramos is starting his 23rd straight game.
Tyler Moore starts at first base instead of Adam LaRoche.
In a surprise, Stephen Strasburg is not listed as the Nationals starter tonight.
The Nationals are sticking with their usual lineup against veteran Aaron Harang.