When the Senate opened for business Monday, observers saw a familiar face in an unfamiliar place.

Senate Judiciary Chairman Patrick J. Leahy, D-Vt., presided over the opening of the chamber, leading the Senate in the Pledge of Allegiance and recognizing Majority Leader Harry Reid for his opening comments.

“It’s very unusual to have one of the most senior members of the Senate presiding, and especially at this time of the day,” the Nevada Democrat said with Leahy in the chair. “We had a little emergency here today. The senator that was expected to be here — because of the fog that we have around the eastern part of the United States — was unable to be here, and you agreed to come.”

The job of presiding over the Senate is a largely thankless task that falls to the chamber’s more junior members. Newer Democrats Richard Blumenthal of Connecticut and Chris Coons of Delaware often preside Monday afternoons.

Leahy, by contrast, is the Senate’s second-most senior member.

Reid praised Leahy for their long friendship, including during the difficult times in Reid’s personal life in recent years. Reid’s wife Landra has had several serious medical issues in recent years, namely a serious car accident and a bout with breast cancer.

Dense fog over the Washington, D.C., area caused nightmares for travelers, including for senators trying to get back to work for a Monday evening cloture vote. Numerous flights into Ronald Reagan Washington National Airport were canceled due to the visibility issues.

The weather prompted the Senate to delay that vote until Tuesday afternoon. No word yet on any delay in the Senate’s Secret Santa program, which is organized by Minnesota Democrat Al Franken.