Alert archive / Minnesota / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 72, NWS Duluth, MN

July 21, 2001Lake County, Minnesota

NWS Duluth, MN issued this severe thunderstorm warning at Jul 21, 2001, 6:22 PM CDT for Lake County, Minnesota. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 21, 2001, 6:22 PM CDT (23:22 UTC)
Expired
Jul 21, 2001, 7:00 PM CDT
In force
38 min
Issued by
NWS Duluth, MN
Area
Whole counties

County Lake County, MN

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.4 hours before the alert went out and 342 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 2001-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1431 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 2001-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.19395878Sfc1 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
1431 J/kg
Mixed-layer CIN
-146 J/kg
Mixed-layer LCL
975 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

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 Jul 21, 2:45 PM CDT, 3 hours 37 minutes earlier.

Area forecast discussion, Jul 21, 2:45 PM CDT, 3 hours 37 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
245 PM CDT SAT JUL 21 2001

FORECAST CONCERNS ARE SHOWER AND TSTM CHCS ONCE AGAIN...BUT ALSO
COLD FRONT PASSAGE SUN NIGHT/MONDAY. MODEL DIFFERENCES ONCE AGAIN
WITH PLACEMENT AND TIMING THROUGHOUT THE FORECAST. WILL TRY A BLEND
AGAIN TODAY.

RUC80 MATCHING WELL WITH THE H5 VORT PUSHING ACROSS N MN ATTM. ONLY
A FEW LIGHT SHOWERS BEING GENERATED RIGHT NOW. THE LAGGING SOUTHERN
PORTION OF THIS H5 SHORTWAVE WILL HAVE A BETTER CHANCE AT TRIGGERING
SOME TSTMS LATER THIS AFTERNOON AND EVENING AS MORE SUN AHEAD OF IT
WILL HELP DESTABILIZE THE AIRMASS. WILL PUT IN SOME EVENING TSTMS IN
SE HALF OF CWA TO COVER THIS WAVE...BUT WILL UPDATE WORDING NEAR
ZONE ISSUANCE TIME. NEXT MCS PROJECTED TO TAKE AIM AT OUR W ZONES
LATE TONIGHT AND SUNDAY...BUT MODELS DIVERGE GREATLY HERE. AVN HITS
ONLY THE N ZONES ON SUNDAY...WHILE ETA/MESO/NGM FOCUS MAINLY S. DAILY
TRENDS HAVE BEEN WEAKENING STORMS AS THEY REACH US BY MORNING...BUT
INSTABILITY PARAMS INDICATING MODERATELY UNSTABLE CONDITIONS STILL
BY 12Z SUN. HOWEVER...WILL NOT GO TOO STRONG ON TSTM WORDING LATE
TONIGHT AND SUNDAY WITH THE SIGNIFICANT MODEL DIFFERENCES.

MODELS TO AGREE IN LATER PERIODS ON DRAGGING A PRE-FRONTAL TROF
THROUGH OUR CWA ON SUNDAY NIGHT. AVN IS MORE AGGRESSIVE HERE WITH
FOCUS AND STRENGTH OF THE TROF. MODELS WERE INITIALLY SHOWING THIS
AS THE COLD FRONT PASSAGE...BUT NOW HOLD THE COLD FRONT BACK NORTH OF
THE CANADIAN BORDER UNTIL MONDAY NIGHT. WILL GO WITH 40 POPS MOST
ZONES WITH TROF PASSAGE SUN NIGHT. MODELS DO ALSO AGREE ON A
SHORTWAVE HITTING OUR WI ZONES MONDAY MORNING FROM THE SW. WILL GO
WITH POPS THERE BUT KEEP OTHER AREAS DRY. A FEW BORDER HOPPING
SHOWERS OR STORMS MAY GENERATE IN THE VICINITY OF THE COLD FRONT...
SO MAY THROUGH IN 20 POPS IN OUR FAR NW ZONES MONDAY/MONDAY NIGHT.

MODELS ARE BASICALLY GOING FOR A DRY FRONTAL PASSAGE ONCE IT DOES
MOVE THROUGH ON TUESDAY MORNING. JUST A FEW SHOWERS HINTED ALONG THE
CANADIAN BORDER. WILL LEAVE TUES DRY FOR NOW IN THE EXTENDED.

PERSISTENCE TEMPS HAVE WORKED OUT WELL AND WILL FOLLOW THAT TREND
AGAIN. ONCE AGAIN...GOING A BIT CLOSER TO WARMER FWC.

.DLH...NONE.

SHIMON

The office that day

Everything else NWS Duluth, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 5:18 PM CDTSevere Thunderstorm WarningDLHLake, Saint Louis57 min

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; the sounding from the Mesonet's radiosonde archive.