Two inches of snow or a trace of freezing rain or ice — even the anticipation of such precipitation — is all it will take now for officials to shut down a portion of the George Washington Memorial Parkway.

The new National Park Service guidelines apply to the northern section of the parkway, between Spout Run Parkway and the Beltway, which is undergoing a major rehabilitation project.

The National Park Service said the northern section of the George Washington Memorial Parkway “will close for storms forecasting 2 or more inches of snow or any amount of freezing rain or ice.” It said that portion of the parkway will “close 4 hours before the forecasted start of the storm,” adding that drivers “will need to seek alternate routes.”

Traffic will continue along the northern section of the parkway “during storms forecasting less than 2 inches of snow with no freezing rain or ice,” according to a news release.

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