Tornadoes · United States · New Jersey · 2003
F1 tornado, Sergeantsville, New Jersey, September 23, 2003
This F1 tornado ran 2.6 miles across Hunterdon County on September 23, 2003, touching down at 7:52 AM EDT and reaching 50 yards wide. It killed nobody, and did $500,000 of property damage.
The rating scale
Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
F040 to 72 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
F4207 to 260 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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.
The record
- Rating
- F1
- Date
- September 23, 2003
- Touchdown
- 7:52 AM EDT (11:52 UTC)
- Path length
- 2.6 miles (4.2 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $500,000
- County
- Hunterdon County
- Touchdown point
- 40.450, -74.920
- Lift-off point
- 40.480, -74.850
- Record number
- 646
What the Weather Service recorded
An F1 (on the Fujita Scale) tornado touched down in Hunterdon County in Delaware and Raritan Townships. It touched down around Zentek Road and Green Farm Lane. It moved east across Lambert Lane, Sandbrook-Headquarters Road, Yard Road, County Route 579 and lifted over the Copper Hill Country Club in Raritan Township just before reaching New Jersey State Route 31 and U.S. Route 202. Numerous trees and wires were uprooted. The property wind damage in Delaware Township occurred along Yard Road and County Route 579. On Yard Road, a two story barn and a chicken coop were destroyed. In all about a dozen properties on Yard Road suffered damage. They had holes in their roofs, porches flattened, windows shattered, barn doors pulled and siding torn away. A piece of one roof was carried one quarter of a mile. Substation power lines were torn down in the township and caused most of the 8,000 outages in the county. A ten-by-ten barn was carried by the tornado and dropped on County Route 579. A barn was blown off its foundation on County Route 579. A garage was flattened by a tree on the county road; another had a trampoline blown onto it. In Raritan Township, the wind damage was concentrated around the Cooper Hill Country Club and Hampton Corner Road. Two homes were damaged by fallen large trees. The tornado remained on the ground for about 2.6 miles, its path width was about 50 yards and the estimated maximum wind speed was about 75 mph.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 11:54 UTC | 12:30 UTC | Severe Thunderstorm Warning | PHI |
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 forecast that day
The Storm Prediction Center had this point in a General Thunderstorms Risk. The outlook in force was issued at 05:16 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 air that afternoon
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.
Phillips Aaf/Abe, MD (KAPG), 12:00Z
0.1 hours after it, 152 km from the path. September 23, 2003.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -4407 J/kg
- Surface CAPE
- 78 J/kg
- Mixed-layer LCL
- 705 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -118 m²/s²
- 0-3 km storm-relative helicity
- -69 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.8 K/km
The surface observations
Trenton/Mercer Co. (TTN), 22 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 09:53 UTC | 72 | 70 | 170° 16 kt | 20 | 1008.5 | |
| 10:08 UTC | 71.6 | 69.8 | 170° 15 kt | 20 | 1008.1 | |
| 10:53 UTC | 73 | 70 | 170° 13 kt | 20 | 1007.5 | |
| 11:01 UTC | 73.4 | 71.6 | 170° 15 kt | 21 | 1007.5 | -RA |
| 11:10 UTC | 73.4 | 71.6 | 180° 14 kt | 21 | 1007.5 | |
| 11:53 UTC | 72 | 71 | 180° 12 kt | 21 | 1007.1 | -RA |
| 12:10 UTC | 71.6 | 71.6 | 170° 12 kt | 1006.8 | -RA | |
| 12:17 UTC | 66.2 | 66.2 | 320° 14 kt | 23 | 1007.5 | +RA BR |
| 12:23 UTC | 64.4 | 62.6 | 290° 11 kt | 1008.5 | +RA BR | |
| 12:25 UTC | 64.4 | 62.6 | 300° 10 kt | 1008.1 | +RA BR | |
| 12:36 UTC | 62.6 | 62.6 | 310° 11 kt | 1008.1 | RA BR | |
| 12:44 UTC | 64.4 | 62.6 | 290° 8 kt | 1008.1 | RA BR | |
| 12:53 UTC | 64 | 63 | 280° 6 kt | 15 | 1008.8 | RA BR |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Philadelphia radar (KDIX), 70 km away, was scanning. The volume nearest the touchdown began at 11:53 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.
This ground now
The live radar over the trackEvery 2003 tornado in New JerseyEvery tornado in New Jersey since 1950Warnings in force in New Jersey nowThe forecast where you are
The other tornadoes of September 23, 2003
10 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| September 23 | 4:30 AM EDT | F0 | Lunenburg, VA | 1.0 | 100 | $20,000 | ||
| September 23 | 4:45 AM EDT | F0 | Nottoway, VA | 0.5 | 50 | $10,000 | ||
| September 23 | 5:30 AM EDT | F1 | Amelia, VA | 2.0 | 100 | 2 | $30,000 | |
| September 23 | 5:45 AM EDT | F0 | Chesterfield, VA | 3.0 | 100 | $10,000 | ||
| September 23 | 6:09 AM EDT | F1 | City of Richmond, VA | 2.0 | 100 | $30,000 | ||
| September 23 | 6:15 AM EDT | F1 | Henrico, VA | 3.0 | 100 | $30,000 | ||
| September 23 | 6:24 AM EDT | F1 | Hanover, VA | 2.0 | 80 | $10,000 | ||
| September 23 | 7:20 AM EDT | F1 | Montgomery, PA | 0.8 | 100 | $1.0 million | ||
| September 23 | 8:14 AM EDT | F1 | Burlington, NJ | 1.8 | 120 | $600,000 | ||
| September 23 | 8:15 AM EDT | F1 | Mercer, NJ | 5.0 | 100 | $1.0 million |
What this means
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.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.