Time-height – Omega and negative EPV
Notes:
The data on this slide is from a time-height diagram taken at a point in central NY, near where the maximum snow fell during the event. Note that upward vertical motion greater than 8 microbars per second was co-located with negative EPV for approximately 6 hours at this point. The co-location of strong upward motion and negative EPV (a * signature) was at least 50 mb deep for about 3 hours, and slightly less than 50 mb deep for another 3 hours. Local research at BGM indicates that * signatures that persist for at least 3 hours, and are at least 50 mb deep are often associated with significant (greater than 9 inches) snow bands. This event appeared to be associated with a * signature with depth and persistence near the lower bound of this heavy snow threshold.
Slide 13