F0 tornado, Arlington, Minnesota, August 3, 2002

1. F040 to 72 mphthis tornado

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

2. F173 to 112 mph

   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

F0

Date

August 3, 2002

Touchdown

6:21 PM CDT (23:21 UTC)

Path length

0.5 miles (0.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Sibley County

Touchdown point

44.630, -94.030

Lift-off point

44.630, -94.030

Record number

800

Touched down in open field.

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

6 minutes of warning. NWS MPX issued a tornado warning for this county at 23:15 UTC, 6 minutes before the tornado touched down, in force until 00:00 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 20:19 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.

NWS Twin Cities, MN wrote its last area forecast discussion before the tornado touched down at Aug 3, 3:05 PM CDT, 3 hours 16 minutes earlier.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
305 PM CDT SAT AUG 3 2002

FORECAST CONCERN CONTINUES TO BE FLOODING AND SEVERE WX. CURRENT MCS
STILL PRODUCING SOME HEAVY RAIN AND SMALL HAIL NORTH OF THE METRO
AREA AND HINTS OF NEW CELLS DEVELOPING OVER WEST CENTRAL MN.
POTENTIAL SVR CELLS DEVELOPING OVER EASTERN SD IN HOT PROD AND THETA
E AXIS NEAR SFC LOW. THINK POTENTIAL FOR FLOODING DOWN A LITTLE BIT
IN CENTRAL MN BUT FAVORABLE THICKNESS AND CURRENT ACTIVITY FAVORS
EVENING WORDING. AXIS OF POTENTIAL HEAVY RAIN AXIS MAY THEN SHIFT
SOUTH LATER THIS EVENING WITH RENEWED THETA E ADVECTION. PRECIP
WATER VALUES STILL FORECAST OVER 2 INCHES WITH STRONG SUBTROPICAL
FEED. ETA A LITTLE FASTER PUSHING RAIN THROUGH BY SUNDAY MORNING BUT
WILL KEEP CHANCES GOING IN FAR SOUTHERN MN. SVR THREAT MOST LIKELY
IN SW OR WEST CENTRAL BUT WDL PROFILER NOT SHOWING MUCH SPEED SHEAR.
BEST CHANCE FOR A FEW HOURS THIS EVENING AND THEN MORE INTO A HEAVY
RAIN SITUATION.
NO MUCH

.MSP...FLOOD WATCH THIS EVENING CENTRAL AND EC MN
       INCLUDING ILL/STC/CBG/JMR
       MNZ044-045-049>052-057>059

       FLOOD WATCH TONIGHT SW MN INTO WC WISC
       INCLUDING RWF/JYG/MKT/HCD/MSP/RGK/RPD/EAU
       MNZ053-060>063-065>070-073>078-082-083-WIZ014>016-023>028
JPR

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.

Glencoe (GYL), 15 km from the path, in the two hours either side.

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

The Minneapolis radar (KMPX), 44 km away, was scanning. The volume nearest the touchdown began at 23:18 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 MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

1 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.