Confirmed: Storm surveys find 2 tornadoes

The National Weather Service storm surveys confirmed two tornado touchdowns from Thursday’s severe thunderstorms.

The first was in Rock Stream, near the southwest shore of Seneca Lake. The second was coming into Cortland.

Both of these tornadoes were spawned by the same supercell that was embedded within the larger line of severe storms. This supercell showed signs of rotation for over 130 miles, starting near Bath and continuing east-northeast to south of Herkimer.

Here are the details and maps for both tornado events:

Rock Stream Tornado

Data from the NWS Binghamton Public Information Statement:

Archive Link: https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=PNSBGM&e=202606192100

Rating: EF-1
Estimated Peak Wind: 90 mph
Path Length /statute/: 1.21 miles
Path Width /maximum/: 150 yards
Fatalities: 0
Injuries: 0

Start Date: 06/18/2026
Start Time: 10:55 AM EDT
Start Location: 1 W Rock Stream / Yates County / NY
Start Lat/Lon: 42.4678 / -76.9309

End Date: 06/18/2026
End Time: 10:57 AM EDT
End Location: 1 NE Rock Stream / Yates County / NY
End Lat/Lon: 42.4704 / -76.9075

Survey Summary:
An EF-1 Tornado hit Rock Spring, NY during late morning on June 18, 2026. Though there were pockets of minor tree damage from the storm itself, tornadic damage started around Reading Road at 1055 AM. This tornado strengthened to as much as 90 mph from Old Lake Road to State Route 14, as rotation tightened with the storm itself quickly moving at 50 mph from higher elevations into the Seneca Lake basin. Numerous trees were uprooted in a convergent chaotic fashion, and around 40 vineyard posts were snapped. Twigs and branches were impaled into the ground as missiles in portions of the vineyard, and shingles were found more than a quarter mile from their source. A garage outbuilding collapsed, with some peeling back of a metal roof and siding damage also noted on the residence with small branches squeezing into gaps. After crossing State Route 14 with a continued corridor of uprooted trees, the tornado ended at the Seneca Lake shore around 1057 AM near Fir Tree Point. Spotty tree damage was found on the other side of the lake, but not consistent with tornadic winds.

Cortland Tornado

Archive Link: https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=PNSBGM&e=202606192153
Rating: EF0
Estimated Peak Wind: 80 mph
Path Length /statute/: 1.89 miles
Path Width /maximum/: 200 yards
Fatalities: 0
Injuries: 0

Start Date: 06/18/2026
Start Time: 11:32 AM EDT
Start Location: 3 WSW Cortland
Start Lat/Lon: 42.5901 / -76.2445

End Date: 06/18/2026
End Time: 11:34 AM EDT
End Location: 1 NNW Munsons Corners
End Lat/Lon: 42.5937 / -76.2078

Survey Summary:
An EF-0 tornado briefly touched down 3.4 miles WSW of Cortland in Cortland County NY around 11:32 AM, moving east-northeast at 50 mph. Tree damage along the route was the most common type of
damage, with a swath of tree damage showing a convergent pattern, which is indication of a brief tornado touching down. Going east along Route 222, and along residential streets south of Route
222, multiple trees fell in the east-northeast direction, with a few falling due north. Where convergent damage was evident was just north of the Cortland County Airport, with a few trees
falling in the southwest direction. Among the damage, some of the most extensive was mainly large uprooted trees and large snapped trees. Going further east-northeast, further scattered tree
damage was observed, but did not show a convergent pattern. This indicated that the brief tornado dissipated before heading into town, and was residual thunderstorm wind damage.