Monday, July 02, 2012

Natural Fireworks...Twice On The 4th?

Because once isn't enough...Mother Nature is thinking about giving the Delaware Valley two fireworks shows on the 4th in the au natural style. Yep, more thunderstorms are in the forecast...early and late.

Computer modeling from the NAM, Euro, and GFS all show the potential of a MCS (mesoscale convective system, not to be confused with MSG) in the Great Lakes on Tuesday afternoon.  A MCS is a thunderstorm complex that's not as powerful as a derecho but still can pack some pretty impressive pop as it moves through.  This will ride east and then southeast through the Great Lakes and Pennsylvania, buoyed by the heat ridge in the atmosphere over the Great Lakes pushing east, pushing a warm front through.  It is with this push of heat in the atmosphere where thunderstorms will fire in the late afternoon and evening hours...and gradually continue through the night over our region.  Gusty winds and some localized downpours are likely.  The NAM, below, shows a potential radar image from Midnight tomorrow night in one of the higher resolution runs.

Adding to this, as the warm front pushes east, a weak cool front will push towards the region on Wednesday afternoon.  More thunderstorms will break out along and ahead of the frontal boundary in the afternoon hours in the hot and humid airmass.  The Storm Prediction Center has people north of a Wilmington-Barnegat line under a slight risk for severe weather on Wednesday as storm development could be rather strong.  I wouldn't be surprised if that slight risk gets shifted farther south to include areas impacted by last Friday's storms.