Slide 11 of 52
On this 850 mb analysis for 12Z September 6th, the numbers in the lower left quadrant of the station model are dew point depressions. The BUF 850 mb dew point at this time was -5 degrees C, while the PIT 850 mb dew point was +16 degrees C. Looking at the surrounding stations, it appears that this area of high low level moisture was not very large. This was confirmed by infared satellite imagery (not shown), which indicated an eliptical area of moisture across eastern OH, western PA, and most of WV, moving slowly northeast. Both the previous 00Z, and subsequent 12Z runs of the Eta model did a very good job initializing this area of low level moisture. The NGM was never able to successfully resolve it.