Severe Storms of Friday the 13th (August 1999)



On the evening of Friday the 13th (August 1999) a supercell thunderstorm developed near the junction of Mohawk River and Schoharie Creek Valleys. (See map below). This thunderstorm moved from Esperance and Burtonsville eastward along the Albany and Schenectady County border. A rotating thunderstorm base known as a wall cloud (often a precursor to a tornado) roamed through the sky in this area. The thunderstorm traveled over Guilderland and into Colonie's Maywood neighborhood where 80 to 100 mph straight line downburst winds also caused extensive damage, including dozens of large trees broken off or uprooted and many homes and vehicles damaged or destroyed by falling trees. The damage became more sporadic through Niskayuna and other parts of the town of Colonie. The storm finally made its way into Rensselaer County near route 142 and ended near Deepkill Road.



Damage Map of Supercell Storm



Reflectivity Image of Storm



Storm Relative Velocity Image



Damage Pictures

#1 Tree uprooted along Bozenkill Road in Town of Knox

#2 Southern area of concentration of damage a few hundred feet east of #1 in the area of downdraft winds.

#3 Damage near Pleasantdale, north of Troy

















WSR-88D Doppler Radar Base Reflectivity Image for 810 pm EDT Aug 13, 1999. Hook echo between Troy and Brunswick shows location of meso-cyclone associated with the supercell. WSR-88D Doppler Radar Base Reflectivity Iamge for 810 pm EDT Aug 13, 1999. Hook echo between Troy and Brunswick shows location of meso-cyclone associated with the supercell.