F1 tornado, Whaley Lake, New York, May 31, 2002

1. F040 to 72 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. F173 to 112 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. F2113 to 157 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. F3158 to 206 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. F4207 to 260 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. F5261 to 318 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

F1

Date

May 31, 2002

Touchdown

7:03 PM EDT (23:03 UTC)

Path length

0.5 miles (0.8 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Property damage

$40,000

County

Dutchess County

Touchdown point

41.550, -73.670

Lift-off point

41.550, -73.670

Record number

679

During Friday afternoon and early evening of May 31, a strong cold front clashed with a very unstable air mass across eastern New York State. In addition, there were strong and divergent winds aloft. All of these parameters set the stage for the largest widespread severe event in eastern New York State in exactly four years. Including adjacent New England, 42 warnings were issued from the Albany office, and nearly as many severe events took place. While most of the events were strong winds associated with the thunderstorms, large hail was reported and two tornados confirmed by a National Weather Service Team. A line of thunderstorms first entered Herkimer County, where numerous trees fell in the town of Ilion. Then, the first of two seperate tornados briefly touched down in Johnstown, Fulton County. That tornado was ranked as a F1 on the Fujita scale with top winds estimated around 100 mph, a width of 25 yards and a path length of about a tenth of a mile. The tornado damaged an old movie theater in that town by tearing the roof off and blowing out the supporting back brick wall. The debris was thrown up to a third of a mile away. Thunderstorm downburst winds also toppled 2/3 of WENT radio's tower and destroyed a wide swath of trees, 8-18 inches in diameter, from about a 1/2 mile southeast of Johnstown to about 1/2 of a mile across Route 30A. Many roads were temporarily closed in and around Johnstown as the result of downed and uprooted trees and large limbs. As the line of storms progressed to the east, minor to moderate wind damage, mainly downed trees and power lines, were noted at various places in Albany, Washington,Warren, Saratoga Schenectady, Schoharie, Columbia, Montgomery, and Rensselaer, Counties. In Dutchess County, in addition to scattered downed trees and wires countywide, a car was crushed by a tree near Poughkeepsie. Ulster County was especially hard hit, with trees and power lines reported down countywide. The second confirmed tornado touched down at Whaley Lake in southeast Dutchess County. This tornado was also ranked between an F0/F1 on the Fujita scale with winds estimated around 75 mph and witnessed by a skywarn spotter. This tornado was about 100 yards wide and had a length of approximately half a mile. Damage was mainly confined to many downed and twisted trees, but one large tree did fall on a small house near the lake and damaged the roof. The tree size ranged between 8 and 24 inches in diameter. Dime-size hail was first reported in Johnstown, Fulton County from a second distinct thunderstorm cell. Hail, as large as 1.75 inches fell in New Paltz, Ulster County . In Dutchess County, dime-size hail fell at Salt Point, while one inch hail was reported at Wingdale (very close to the tornado touchdown) and 1.25 inch hail was noted in Poughkeepsie. One and three quarter inch size hail was reported. The thunderstorms knocked out power to about 9,000 customers in eastern New York, with nearly a third of these in the Mohawk Valley. Despite all the severe weather, no weather-related casualities were reported to the National Weather Service.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

4 minutes of warning. NWS ALY issued a tornado warning for this county at 22:59 UTC, 4 minutes before the tornado touched down, in force until 23:30 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:16 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Poughkeepsie (POU), 20 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Brookhaven radar (KOKX), 102 km away, was scanning. The volume nearest the touchdown began at 23:03 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

The live radar over the trackEvery 2002 tornado in New YorkEvery tornado in New York since 1950Warnings in force in New York nowThe forecast where you are

10 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.