Severe Weather Outlook for Friday, July 31, 2009...

Discussion... as of 1AM 07/31/2009
Not much change from previous thinking. In the grand scheme of things, damaging straight-line winds will be the most widespread form of severe weather. However, where destabilization is maximized, potential for rotating supercells exists given the amount of right-turning in the 0-3km layer. Given the amount of helicity, and taking Wednesday's event with a grain of salt, hard to believe a few tornadoes won't occur by the end of the day. This axis of potential looks to be focused over Eastern MD, Southeastern PA, Southern NJ, and Delaware where SBCAPE is expected to be in the 1000-2000 J/KG range.

Lesser instability is likely to the north and south of this region, hence potential should be geared more toward low-topped convection and damaging wind potential, with hail/tornadoes a lesser threat. Flash flooding will also be of concern, especially in areas that have already been inundated this week.

..EGAN.. 07/31/2009

Previous Discussion below...

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Discussion...
Looking at Tomorrow's setup, things look super interesting.

Biggest question will definately surround the amount of instability. However, this will be the only limiting factor working against a solid outbreak. Kinematic environment is certainly supportive for severe, with a tremendous amount of shear being modeled, both in the lower and middle levels. In conjuction, there's also an abundance of helicity in place will enhances the threat for rotating storms.

Given such a highly sheared environment, instabilty will need to be that much stronger for updrafts to survive the vertical ascent sufficient for supercells, without being tipped or sheared off. This makes the hail and tornado threat somewhat conditional, but in either case, damaging wind threat is there with potential for some fast-moving mini-bows/segments. Where sufficient instability develops, given the amount of shear and right-turning in the lower/mid-levels, potential will certainly exist for rotating supercells and an enhanced hail/tornado threat.

..EGAN.. 07/31/2009