GFS 850 mb Temp valid 12z 2/2
Notes:
The GFS 850 mb temperature trends can be seen on this slide. Again, all forecasts are valid at 12z on the 2nd. The oldest forecast (a 60 hour forecast) is on the lower right. The newest (a 12 hour forecast) is on the upper left. Again, the coldest run looks to be the 06z run on the 31st, showing the 850 mb zero line over southern Pa. Eventually, the 850 mb zero line ended up being over upstate NY.
Slide 6