23/00 UTC Eta 00-hr forecast cross section of frontogenesis, relative humidity, and EPV.

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Speaker Notes:

This cross section was taken near the east edge of the dry slot over east central NY at 00 UTC. Negative EPV can be seen above a sloped region of frontogenesis, however the presence of the mid-level dry slot was associated with only marginal relative humidity in that area. Typically, the combination of negative EPV collocated with deep saturation is required for CSI and intense slantwise convection. The type of situation shown in this slide typically leads to an enhanced frontogenetical circulation, and broad bands of moderate snow.