Labor Day Derecho (Severe T-Storm Outbreak)
Early Morning: Sept 7, 1998

After a very quiet summer with no significant severe weather outbreaks following the Mechanicville-Stillwater tornado and widespread damaging wind event on Memorial day, widespread organized severe weather returned to New York and New England during the pre-dawn hours on Labor day. A violent line of t-storms (a derecho) developed in advance of a strong push of dry chilly air moving in from southeast Canada sweeping east across New York and New England waking most from a sound sleep. The storms produced widespread wind damage and many produced large hail. It's interesting to note here that the season's most violent outbreaks of thunderstorms occurred on the unofficial start of summer, Memorial day, and the unofficial close of summer, Labor day.

An usually warm and increasingly humid day, by early September standards, preceded the t-storm outbreak. Plenty of sunshine, heating the warm sector of air ahead of an advancing cold front and developing low pressure system, pushed daytime temperatures to the upper 80's in eastern New York with dewpoint temperatures rising into the mid and upper 60's by mid to late afternoon on Sunday, the 6th. The cold front was oriented from west to east along the New York, Canada border during the afternoon and only very slowly pushed southward through the day and night. Strong winds blowing in the upper atmosphere set the stage for damaging t-storm winds later in the night.

High dewpoint air continued to pool in advance of the front throughout eastern New York and New England overnight and air temperatures remained in the mid to upper 70's past midnight into Labor day Monday.

An upper level disturbance, or cold pool of air aloft, triggered the line of t-storms over southeast Canada around 10pm on the 6th. The line, caught in the fast flow of air aloft, pushed east at speeds of 50mph, racing across New York and into New England. The warm humid air ahead of the squall line acted as fuel to support the storm's advance. The strength of the dynamics in the atmosphere overcame the lack of daytime heating, normally required for severe weather in the Northeast, allowing the squall line to remain severe through the pre-dawn hours.

The line struck the counties in eastern New York around 2am and continued through the Channel 6 coverage area into western New England through 4am. Embedded within the squall line was a supercell t-storm (a storm with its own rotating center) which produced an extensive damage path from Syracuse all the way down the Mohawk valley into western Vermont. Several small tornadoes may have been spawned by this individual cell within the larger line. This particular storm also produced almost continuous lighting creating daylight conditions as described by many in its path. The following is a listing of storm reports compiled by the National Weather Service and here at Channel 6.




Storm Report

Estimated Time

Old Forge Herkimer NY .88" Diameter Hail 12:48 am
Cooperstown Otsego NY Wind Damage, trees and wires down 2:15 am
Herkimer Herkimer NY Wind Damage, trees and wires down 2:17 am
Fairfield Herkimer NY 78 mph wind gust 2:18 am
Little Falls Herkimer NY .75" diameter hail, widespread tree damage 2:20 am
Mohawk Herkimer NY .88" diameter hail, limbs down 2:20 am
Gloversville Fulton NY 60mph wind gust, trees/limbs down 2:40 am
Glen Montgomery NY 80 mph wind gust 2:42 am
Ft. Plain Montgomery NY .75" diameter hail, and 60 mph wind gust 2:45 am
St. Johnsville Montgomery NY Widespread wind damage 2:50 am
Sidney Delaware NY Wind damage 3:00 am
Jonesville Saratoga NY Widespread wind damage, Burnt Hills, Ballston Spa 3:05 am
Schuylerville Saratoga NY .75" Diameter Hail and 50 mph winds 3:15 am
Oppenheim Fulton NY Wind damage, Trees and wires down 3:20 am
Schaghticoke Rensselaer NY Wind damage, trees and wires down 3:20 am
Fort Edward Washington NY .75" diameter hail 3:33 am
Pleasantdale Rensselaer NY Wind damage, boat capsized on the Hudson 3:50 am
Saratoga County Northwest part of county NY Widespread tree and power line damage 3:50 am
Woodford Bennington VT Wind damage, trees down 4:00 am