The Commonwealth is divided this Saturday, between plenty of sun in the northern half of the state, and persistent cloud-cover over the southern half closer to the cold front that moved through overnight. This front is associated with an upper-level trough that dug into the Northeast Friday. At the base of this trough, drier air is evident in the water vapor image below, as indicated by the orange-red shades (drier, warmer air from higher up in the atmosphere sinking). Notice that where we have sunny skies today is right where that dry air at the upper-levels is present.
