12Z Surface Plot
Slide 12 of 52
Because of the nocturnal inversion, the area of low level moisture was not apparent on surface charts, such as this one from 12Z September 6th. (Recall that the PIT sounding also indicated the moist layer was not surface based.) Satellite imagery at this time (not shown) indicated the leading edge of the moist layer was near Erie, PA (ERI). Also note that Elmira, NY (ELM), has radiated down to a temperature of 52 degrees.