F0 tornado, Lake Crystal, Minnesota, July 9, 2003

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

July 9, 2003

Touchdown

5:40 PM CDT (22:40 UTC)

Path length

0.1 miles (0.2 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

County

Blue Earth County

Touchdown point

44.170, -94.280

Lift-off point

44.170, -94.280

Record number

345

Brief touchdown in a bean field.

Brief touchdown on the extreme eastern edge of town, near the intersection of Kraus Street and Blue Earth Street. Several trees were damaged. The storm which produced this tornado also produced widespread strong wind damage throughout central and western sections of Lake Crystal (see corresponding entry).

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

33 minutes of warning. NWS MPX issued a tornado warning for this county at 22:07 UTC, 33 minutes before the tornado touched down, in force until 23:00 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 20:07 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 Jul 9, 4:28 PM CDT, 1 hour 12 minutes earlier.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
428 PM CDT WED JUL 9 2003

LOW PRES TROUGH CENTERED OVER THE MINNESOTA...SLOWLY MOVING EAST
INTO THE EASTERN GREAT LAKES DURING THE NEXT 48 HOURS.  IN THE SHORT
TERM...STRONG VERTICAL SHEAR ALONG WITH COUPLE OF FRONTAL BOUNDARIES
WILL POSE SOME PROBLEMS OVER THE FORECAST AREA EARLY THIS EVENING.

WEAKER SHORTWAVE PUSHING BEHIND THE MAIN LOW PRESSURE TROUGH LATER
TONIGHT AND THURSDAY.  MUCH OF THE ENERGY ASSOCIATED WITH THIS
SYSTEM SHOULD MOVE ACROSS NORTHERN HALF OF THE STATE.  HAVE MENTION
SOME SMALL POPS THURSDAY INTO THE THURSDAY EVENING.

UPPER RIDGE OVER THE WESTERN U.S. AMPLIFY AND SLIDE FURTHER EAST
INTO THE CENTRAL SECTION OF THE NATION TOWARD END OF THE WORK.  DRY
NORTHWESTERLY AIRFLOW PREVAILING THROUGH THE BALANCE OF THE WEEKEND.

.MSP...NONE.

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-101100-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
105 PM CDT WED JUL 9 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND
SOUTHERN MINNESOTA...AND WEST CENTRAL WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS MAY DEVELOP THIS AFTERNOON AND EVENING
ACROSS PORTIONS OF CENTRAL AND SOUTH CENTRAL MINNESOTA INTO WEST
WISCONSIN AS A LOW PRESSURE TROUGH PUSHES ACROSS THE REGION.  BRIEF
HEAVY RAINFALL AND SMALL HAIL WILL ACCOMPANY SOME OF THE STRONGER
THUNDERSTORMS...HOWEVER MOST STORMS WILL REMAIN BELOW SEVERE LIMITS.
THE BEST CHANCE FOR SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING
WILL BE IN SOUTH CENTRAL MINNESOTA CLOSER TO A SURFACE WARM FRONT IN
IOWA.  THE MAIN SEVERE WEATHER RISK IN THIS AREA WOULD BE LARGE
HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION MAY BE NEEDED LATE THIS AFTERNOON
AND EVENING.

MBK

In the hours before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
0445 PM CDT WED JUL 09 2003

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0421 PM    1 W FAIRFAX               MN   0.75 IN HAIL
07/09/03   RENVILLE

BAP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
0523 PM CDT WED JUL 09 2003

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0520 PM    2 S NEW ULM               MN   0.88 IN HAIL
07/09/03   BROWN                          REPORTED BY LAW
                                          ENFORCEMENT

AEB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
0525 PM CDT WED JUL 09 2003

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0520 PM    5 S DANVERS               MN   TORNADO
07/09/03   SWIFT                          REPORTED BY STORM SPOTTER

AEB

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.

New Ulm Municipal (ULM), 24 km from the path, in the two hours either side.

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

The Minneapolis radar (KMPX), 94 km away, was scanning. The volume nearest the touchdown began at 22:41 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 2003 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

20 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.