Alert archive / Minnesota / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 87, NWS Twin Cities, MN

August 21, 2014Martin County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 21, 2014, 4:20 AM CDT for Martin County, Minnesota. It was in force for 40 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
Aug 21, 2014, 4:20 AM CDT (09:20 UTC)
Expired
Aug 21, 2014, 5:00 AM CDT
In force
40 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Martin County, MN

The radar

The Minneapolis radar (KMPX), 167 km from the middle of the area, began a volume at 09:19 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
Aug 21, 1:00 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 9.3 hours before the alert went out and 165 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 2014-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 397 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 2014-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
397 J/kg
Mixed-layer CIN
-58 J/kg
Mixed-layer LCL
1160 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
162 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

702 
WUUS53 KMPX 210920
SVRMPX
MNC091-211000-
/O.NEW.KMPX.SV.W.0087.140821T0920Z-140821T1000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
420 AM CDT THU AUG 21 2014

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN MARTIN COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 500 AM CDT

* AT 417 AM CDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
  EXTENDING FROM 13 MILES NORTHWEST OF FAIRMONT TO 13 MILES EAST OF
  JACKSON TO 6 MILES EAST OF SUPERIOR...AND MOVING EAST AT 40 MPH.

  HAZARD...60 MPH WIND GUSTS AND QUARTER SIZE HAIL.

  SOURCE...RADAR INDICATED.

  IMPACT...HAIL DAMAGE TO VEHICLES IS EXPECTED. EXPECT WIND DAMAGE TO
           ROOFS...SIDING AND TREES.

* LOCATIONS IMPACTED INCLUDE...
  FAIRMONT...WELCOME...CEYLON...WILBERT...FAIRMONT AIRPORT...GRANADA
  AND EAST CHAIN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS OCCURRING WITH THESE STORMS...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 4349 9485 4351 9487 4370 9478 4371 9425
      4349 9425
TIME...MOT...LOC 0920Z 256DEG 36KT 4375 9463 4362 9470
          4343 9479

HAIL...1.00IN
WIND...60MPH

$$

JRB
2 follow-up statements
748 
WWUS53 KMPX 210943
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
443 AM CDT THU AUG 21 2014

MNC091-211000-
/O.CON.KMPX.SV.W.0087.000000T0000Z-140821T1000Z/
MARTIN MN-
443 AM CDT THU AUG 21 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
MARTIN COUNTY UNTIL 500 AM CDT...

AT 440 AM CDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
NEAR FAIRMONT...AND MOVING EAST AT 40 MPH.

HAZARD...60 MPH WIND GUSTS AND QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...HAIL DAMAGE TO VEHICLES IS EXPECTED. EXPECT WIND DAMAGE TO
         ROOFS...SIDING AND TREES.

LOCATIONS IMPACTED INCLUDE...
EAST CHAIN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS OCCURRING WITH THESE STORMS...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 4349 9425 4349 9473 4370 9460 4371 9425
TIME...MOT...LOC 0943Z 256DEG 36KT 4373 9432 4360 9440
          4341 9449

HAIL...1.00IN
WIND...60MPH

$$

JRB
607 
WWUS53 KMPX 210959
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
459 AM CDT THU AUG 21 2014

MNC091-211009-
/O.EXP.KMPX.SV.W.0087.000000T0000Z-140821T1000Z/
MARTIN MN-
459 AM CDT THU AUG 21 2014

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MARTIN COUNTY
WILL EXPIRE AT 500 AM CDT...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE
WARNED AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 AM CDT.

LAT...LON 4349 9425 4349 9473 4370 9460 4371 9425
TIME...MOT...LOC 0959Z 256DEG 36KT 4375 9410 4362 9418
          4344 9427

$$

JRB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 12:24 AM CDTSpecial Weather StatementMPXLac qui Parle36 min
Aug 21, 12:52 AM CDTSpecial Weather StatementMPXStevens53 min
Aug 21, 2:01 AM CDTAreal Flood WarningMPXStevens, Swift6 hr
Aug 21, 2:33 AM CDTFlash Flood WatchMPXAnoka, Blue Earth, Carver, Chippewa, Dakota, Douglas and 21 more4 hr
Aug 21, 2:50 AM CDTSpecial Weather StatementMPXBrown, Martin, Watonwan85 min
Aug 21, 3:07 AM CDTSpecial Weather StatementMPXChippewa, Kandiyohi, Pope, Swift83 min
Aug 21, 3:53 AM CDTAreal Flood WarningMPXBrown, Watonwan5 hr
Aug 21, 4:31 AM CDTSpecial Weather StatementMPXBlue Earth, Nicollet59 min
Aug 21, 4:47 AM CDTSevere Thunderstorm WarningMPXFaribault43 min
Aug 21, 5:10 AM CDTSevere Thunderstorm WarningMPXBlue Earth, Faribault, Waseca50 min
Aug 21, 7:16 AM CDTHeat AdvisoryMPXBlue Earth, Brown, Carver, Dakota, Faribault, Freeborn and 14 more13 hr
Aug 21, 6:20 PM CDTSpecial Weather StatementMPXWatonwan25 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2014Every severe thunderstorm warning in 2014

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.