July 28, 2002

A severe thunderstorm tracked southeast from western Onondaga county across Cortland county during the early evening on the 28^th.  The storm produced widespread tree damage along its path.  At approximately 640 pm, the storm produced an F1 tornado a few miles north of Skeneateles, in the small town of Mottville.  A trailer home was completely destroyed, and major tree damage occurred.

ETA 12hr forecast 250mb wind speed at 12z on the 28th. The jet stream appears to be north of the forecast area, with a speed max extending
from Michigan eastward across upstate New York.

Eta 12 hr forecast 250 mb wind speed verifying at 7/29 00z.  A distinct speed max extends from Lake Huron southeast across northern New York state.  The tornado location is in the right exit region of the jet.

500 mb heights and vorticity at 7/28 12z. Upstate New York is in westerly flow aloft with a moderately strong short wave moving across the
northern Great Lakes and a weak short wave over western New York.

Eta 12 hr forecast 500 mb heights and vorticity verifying at 7/29 00z.   Upstate New York is in a west to northwest flow aloft, with a strong short wave passing well to the north across Quebec.

12 hr Eta Bufkit sounding at SYR verifying 7/29 00z.

Note the classic clockwise turning hodograph.  1-3 km SR Helicity was 182 and 0-3 km shear was 21 m/s.  The forecast CAPE was 842 J/kg, which was probably significantly lower than what actually occurred, based on observations (actual CAPE values may have exceeded 2000 J/kg).

Surface pressure and 850 mb temperature at 7/29 12z.  Low pressure was located over Lake Superior, with a warm advection pattern setting
up across the eastern Great Lakes.

12 hr Eta forecast surface pressure and 850 mb temperature verifying at 7/29 00z.  A pressure trough is located east of the Appalachian mountains with warm advection continuing behind the front.

Return to NWS Binghamton homepage