Eastern NY and western New England were located near the right rear quadrant of a 300 hPa, 105 knot jet streak over eastern Maine and New Brunswick. This jet streak enhanced a plume of upper-level divergence over the region impacted by the severe weather. There was a plethora of instability in place ahead of the back door cold front. The 0000 UTC Local Area Prediction System (LAPS) analysis had surface-based convective available energy (SBCAPE) values of 1000-4000 J kg-1 over eastern NY and western New England. The 0000 UTC sounding at Albany yielded an SBCAPE value of 3948 J kg-1 and mid-level lapse rates approaching 8°C km-1. The Downdraft CAPE value was extremely high at 1697 J kg-1. The sounding exhibited a deep elevated mixed layer from the surface to around 600 hPa, indicative of the potential for strong winds to mix to the surface with the convection. The 0-6 km deep layer bulk shear was only around 25 knots. However, the better deep layer 0-6 km bulk shear was found over central and eastern New England. The KGYX (Gray, ME) sounding had a 0-6 km shear value of 62 knots. The shear increased westward associated with the deep cutoff cyclone over the Canadian Maritimes (Atlantic Canada). The 0-6 km deep layer shear intersected the abundance of instability for a mesoscale convective system (MCS) to develop over western New England. The MCS produced several bowing convective elements, which resulted in widespread straight-line wind damage. There were also some embedded supercells within the organized linear severe convection.
This talk will take a multi-scale approach in analyzing the event from the synoptic-scale to the storm-scale, in order to understand the convective environment associated with the back door cold front that produced the severe weather outbreak on 26-27 May 2010. Observational data used in the analyses will include surface and upper air observations, satellite imagery, and Albany (KENX) WSR-88D 8-bit radar data. The storm-scale analysis will examine some impressive outflow boundaries with the cold pool to the MCS that focused some of the severe convection.