Alert archive / Minnesota / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 18, NWS Twin Cities, MN

April 21, 2007Douglas County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 21, 2007, 10:52 PM CDT for Douglas County, Minnesota. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 21, 2007, 10:52 PM CDT (03:52 UTC)
Expired
Apr 21, 2007, 11:15 PM CDT
In force
23 min
Issued by
NWS Twin Cities, MN
Area
Counties, with a storm outline in the text

County Douglas County, MN

The radar

The Minneapolis radar (KMPX), 200 km from the middle of the area, began a volume at 03:55 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.

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 21, 9:31 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.9 hours before the alert went out and 198 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 00:00Z on 2007-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 16 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2007-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 146 square meters per square second.193958Sfc1 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
16 J/kg
Mixed-layer CIN
-307 J/kg
Mixed-layer LCL
2804 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
146 m²/s²
0-3 km storm-relative helicity
290 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS53 KMPX 220353
SVRMPX
MNC041-220415-
/O.NEW.KMPX.SV.W.0018.070422T0352Z-070422T0415Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1052 PM CDT SAT APR 21 2007

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  DOUGLAS COUNTY IN WEST CENTRAL MINNESOTA...

* UNTIL 1115 PM CDT

* AT 1051 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM...
  CAPABLE OF PRODUCING LARGE HAIL.  THIS STORM WAS LOCATED 5 MILES
  SOUTHWEST OF BRANDON...OR ABOUT 13 MILES WEST OF ALEXANDRIA...AND
  MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  EVANSVILLE...
  BRANDON...

HAIL UP TO ONE INCH IN DIAMETER HAS BEEN REPORTED SIX MILES WEST OF 
BELLINGHAM WITH THIS STORM.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING. PREPARE TO MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE
SUCH AS A BASEMENT OR SMALL INTERIOR ROOM IF A TORNADO IS SPOTTED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 AM CDT SUNDAY
MORNING FOR WEST CENTRAL MINNESOTA.

 LAT...LON 4610 9574 4577 9573 4589 9538 4609 9513

$$

LS
2 follow-up statements
000 
WWUS53 KMPX 220400
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1100 PM CDT SAT APR 21 2007

MNC041-220415-
/O.CON.KMPX.SV.W.0018.000000T0000Z-070422T0415Z/
DOUGLAS MN-
1100 PM CDT SAT APR 21 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR DOUGLAS COUNTY...

AT 1059 PM CDT...DOPPLER RADAR CONTINUED TO INDICATE A SEVERE
THUNDERSTORM...CAPABLE OF PRODUCING LARGE HAIL.  THIS STORM WAS 
LOCATED NEAR BRANDON...AND MOVING NORTHEAST AT 45 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE ROSE CITY...MELBY...LEAF
VALLEY...HOLMES...MILTONA...MILLERVILLE...GARFIELD...EVANSVILLE...
CARLOS AND BRANDON.

THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL. SEEK SHELTER NOW 
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS

LAT...LON 4610 9574 4577 9573 4589 9538 4609 9513

$$

LS
000 
WWUS53 KMPX 220415
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1115 PM CDT SAT APR 21 2007

MNC041-220425-
/O.EXP.KMPX.SV.W.0018.000000T0000Z-070422T0415Z/
DOUGLAS MN-
1115 PM CDT SAT APR 21 2007

...THE SEVERE THUNDERSTORM WARNING FOR DOUGLAS COUNTY EXPIRES AT 1115
PM CDT...

SEVERE STORMS HAVE MOVED OUT OF THE COUNTY. HOWEVER...MORE 
THUNDERSTORMS WERE DEVELOPING IN THE AREA...REMAIN ALERT FOR 
POSSIBLE ADDITIONAL WARNINGS.

LAT...LON 4610 9574 4577 9573 4589 9538 4609 9513

$$

LS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 9:27 PM CDTSevere Thunderstorm WarningMPXStevens33 min
Apr 21, 9:51 PM CDTSevere Thunderstorm WarningMPXLac qui Parle24 min
Apr 21, 9:51 PM CDTSevere Thunderstorm WarningMPXLac qui Parle24 min
Apr 21, 10:14 PM CDTSevere Thunderstorm WarningMPXStevens31 min
Apr 21, 10:58 PM CDTSevere Thunderstorm WarningMPXLac qui Parle19 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2007Every severe thunderstorm warning in 2007

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; radar from the NEXRAD Level II archive.