An upper level disturbance moving across northern New York in combination with an approaching cold front and a very moist unstable airmass in place across Northeast Pennsylvania, produced clusters and lines of thunderstorms during the afternoon of the 6th. The thunderstorms first developed over central New York earlier in the day, moving into the Northern Tier counties by early evening.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BGM wrote it up.
An upper level disturbance moving across northern New York in combination with an approaching cold front and a very moist unstable airmass in place across Northeast Pennsylvania, produced clusters and lines of thunderstorms during the afternoon of the 6th. The thunderstorms first developed over central New York earlier in the day, moving into the Northern Tier counties by early evening. Trees were toppled and the power was knocked out in some places.
The Binghamton radar (KBGM), 49 km away, was scanning. The volume nearest the first event began at 23:20 UTC.
3 thunderstorm wind. Local standard time, as filed.
Strong thunderstorm winds blew down some trees and a few powerlines
Numerous trees were blown down throughout the county.
Strong thunderstorm winds toppled several trees in town.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 1999Every state in 1999This day in weather historyWarnings in Pennsylvania, July 1999
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5712876, 5712877, 5712878.