The anchor wore, then twirled, a sombrero and mentioned that the holiday was the biggest day of the year for margarita sales. She held what appeared to be a margarita.
She tweeted a day later that she got a little carried away and was sorry for the segment.
MSNBC's "Way Too Early" show similarly apologized this week for showing a staff member shaking maracas and taking a swig from what was said to be a tequila bottle.
The holiday marks an 1862 battle victory by Mexican troops.