Time-height diagram of omega and negative EPV
Notes:
This slide shows a time-height diagram of upward vertical motion and negative EPV, for a point in the southwest Catskill mountains. Note the long duration of deep, persistent co-location of upward vertical motion and negative EPV. Previous local research indicates that the probability of heavy snow (greater than 9 inches) increases significantly when strong upward vertical motion and negative EPV are co-located for more than 3 hours, over a layer more than 50 mb deep. In this case, upward vertical motion in excess of 8 microbars per second was collocated with negative EPV through a greater than 50 mb deep layer for over 6 hours.
Slide 12