Both November and December average 18 cloudy days. Because November is one day shorter, it gets listed as the cloudiest month of the year. Yet, that technicality should not take away from the fact that both months tend to be very gray. Plus, when you add the affect of a low sun angle and the short days, many people will have at least some symptoms of Seasonal Affective Disorder or SAD for short.
Often times what breaks up this cloudy pattern are large arctic high pressure systems that tend to bring in the bitterly cold, yet sunnier weather this area often experiences in late December through February. But until then, there will likely be far more cloudy days than sunny ones as this area will tend to be near the storm track for the next several weeks keeping the sky full of clouds and gloom.