Alert archive / Minnesota / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 112, NWS Duluth, MN

August 29, 2001Cass County, Minnesota

NWS Duluth, MN issued this severe thunderstorm warning at Aug 29, 2001, 6:49 PM CDT for Cass County, Minnesota. It was in force for 56 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 29, 2001, 6:49 PM CDT (23:49 UTC)
Expired
Aug 29, 2001, 7:45 PM CDT
In force
56 min
Issued by
NWS Duluth, MN
Area
Whole counties

County Cass County, MN

The radar

The Duluth radar (KDLH), 161 km from the middle of the area, began a volume at 23:52 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 29, 7:35 PM CDTThunderstorm Wind 50 EBackus, MNTrees were blown down.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 29, 3:30 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.8 hours before the alert went out and 240 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2001-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2001-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
8 J/kg
Mixed-layer CIN
-417 J/kg
Mixed-layer LCL
1337 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Duluth, MN wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 29, 3:00 PM CDT, 3 hours 49 minutes earlier.

Area forecast discussion, Aug 29, 3:00 PM CDT, 3 hours 49 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
300 PM CDT WED AUG 29 2001

SEVERE THUNDERSTORM POTENTIAL IS MAIN FORECAST THREAT.

MODELS ALL HAVE A GOOD HANDLE ON TONIGHTS PRECIPITATION EVENT.
WILL HAVE TO SLIGHTLY FAVOR ETA/MESOETA...WHICH HAVE A GOOD
HANDLE ON THE CURRENT CONVECTIVE TRENDS AND SHORTWAVE POSITIONS.

STORMS WERE ALREADY FIRING UP IN THE VICINITY OF THE FRONTAL BOUNDARY
OVER THE RED RIVER VALLEY THIS AFTN. MSAS LI AHEAD OF THE FRONT
WAS IN THE -7C RANGE AS OF 2 PM. THE VORT MAX IN EXTREME WESTERN
NORTH DAKOTA WILL CONTINUE TO MOVE EAST THIS EVENING. THIS COMBINED
WITH H3 DIVERGENCE FROM A SOUTHERN CANADIAN JET WILL PROVIDE
ENHANCED LIFT ALONG THE FRONTAL BOUNDARY THIS EVENING. WILL
CONTINUE WITH THE SEVERE WORDING FOR THE EVENING IN THE ZONES.
NEW WATCH ALREADY OUT WHICH WILL INCLUDE PORTIONS OF OUR AREA.

WILL CARRY A CHANCE OF EARLY MORNING SHOWERS IN PORTIONS OF NW WI
AS WELL...BUT THE REST OF THE AREA SHOULD SEE SOME DECREASE IN
CLOUDS OVERNIGHT. THE CLOUDS WILL COME BACK IN ACROSS THE REGION
ON THURSDAY...ESPECIALLY NORTH OF THE TWIN PORTS. WILL CONTINUE
THE SCATTERED SHOWER WORDING...WHICH SHOULD PRIMARILY BE IN THE
AFTERNOON AS THE SECONDARY TROUGH/COLD FRONT DROPS SOUTH WITH
A SIZEABLE STRATOCUMULUS DECK.

THE CLOUDS WILL CLEAR OUT THURSDAY NIGHT AND FRIDAY AS STRONG
HIGH PRESSURE BUILDS IN. OVERNIGHT LOWS THURSDAY NIGHT MAY DIP
WAY DOWN INTO THE 30S IN THE TRADITIONAL COLDER SPOTS OF NORTHERN
MINNESOTA AS +4C 850 TEMPS START TO PUSH IN. FRIDAY NIGHT COULD
WELL BE EVEN COLDER...WITH THE POTENTIAL FOR FROST IN SOME AREAS.

MESOETA SURFACE TEMPS APPEAR TO BE IN LINE AND HAVE FOLLOWED
THEM FAIRLY CLOSELY OVER THE NEXT FEW DAYS.

.DLH...NONE.

DAP

Nearby

Severe Thunderstorm Warnings in Minnesota, 2001Every severe thunderstorm warning in 2001

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.