ATLANTA — There were partly cloudy skies in Atlanta on Monday, but the overcast looming over the city seemed to be more from the gloom of the Falcons’ gut-wrenching Super Bowl 51 loss. Falcons’ fans are in a somber mood after their team blew a 25-point lead in a 34-28 loss to the New England Patriots on Sunday night. The abundant excitement that engulfed the city leading up to the matchup had been replaced by another heartbreaking sports setback for the A-T-L. Even for fans used to disappointment, this “L” was unprecedented.