EF1 tornado, Dahlgren, Virginia, May 5, 2017

1. EF065 to 85 mph

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

2. EF186 to 110 mphthis tornado

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

3. EF2111 to 135 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. EF3136 to 165 mph

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

5. EF4166 to 200 mph

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

6. EF5over 200 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

EF1

Date

May 5, 2017

Touchdown

9:19 AM EDT (13:19 UTC)

Lifted

9:21 AM EDT (13:21 UTC)

On the ground

2 minutes

Path length

1.2 miles (1.9 km)

Path width

10 yards (9 m)

Deaths

0

Injuries

0

County

King George County

Touchdown point

38.345, -77.019

Lift-off point

38.362, -77.020

Record number

1705050719-01

Low pressure was located across the Tennessee Valley while a strong low level jet transported moisture into the Mid-Atlantic. Showers and thunderstorms developed across Virginia and the unstable atmosphere caused a few thunderstorms to become severe.

The National Weather Service in Baltimore MD/Washington DC has confirmed a narrow, 10 yard wide tornado near Dahlgren in King George County VA on the morning of May 05, 2017.||Peak winds were 90 mph, a level EF-1 on the Enhanced Fujita scale. Damage has been confirmed along a 0.6 mile path from the northeastern corner of Naval Support Facility Dahlgren property, north across Hwy 301 just west of the Harry Nice Bridge, to |Barnesfield Park. NWS storm survey identified the first damage as small limbs on|Higley Rd. A couple trees were snapped as the tornado moved northwest to a parking lot where it turned north. Four cars were flipped in this parking lot at 8:20am by a narrow vortex as confirmed by security camera footage. FAA radars for Joint Base |Andrews and Reagan National airport both depicted some rotation at this time which helped confirm the reported times.||Two trees were snapped in a forest north of this parking lot. The next evident damage was a large uprooted pine tree that fell southwest onto Hwy 301 just west of a visitor center. Several trees were snapped and uprooted on the west side of the parking |lot for the visitor center with tree damage then continuing to Barnesfield Park. Minor damage at the baseball fields in the park included a destroyed equipment shed, bleachers blown into a fence and a damaged metal bench. No further damage was evident on the tree line at the edge of the baseball fields, so this was determined to be the north end of the tornado track.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 12:30 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.

Quantico Mcaf (NYG), 30 km from the path, in the two hours either side.

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

The Sterling radar (KLWX), 80 km away, was scanning. The volume nearest the touchdown began at 13:17 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.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2017 tornado in VirginiaEvery tornado in Virginia since 1950Warnings in force in Virginia nowThe forecast where you are

12 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.