Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 142, NWS Twin Cities, MN

August 14, 2020Polk County, Saint Croix County, Wisconsin; Washington County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 14, 2020, 8:13 PM CDT for Polk County, Saint Croix County, Wisconsin; Washington County, Minnesota. It was in force for 47 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 14, 2020, 8:13 PM CDT (01:13 UTC)
Expired
Aug 14, 2020, 9:00 PM CDT
In force
47 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Washington County, MN, Polk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 68 km from the middle of the area, began a volume at 01:12 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 14, 5:38 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 1.2 hours before the alert went out and 386 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, International Fa, MN at 00:00Z on 2020-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, International Fa, MN at 00:00Z on 2020-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 247 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1019 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
247 m²/s²
0-3 km storm-relative helicity
426 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

835 
WUUS53 KMPX 150113
SVRMPX
MNC163-WIC095-109-150200-
/O.NEW.KMPX.SV.W.0142.200815T0113Z-200815T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
813 PM CDT Fri Aug 14 2020

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Washington County in east central Minnesota...
  Western St. Croix County in west central Wisconsin...
  South central Polk County in northwestern Wisconsin...

* Until 900 PM CDT.

* At 813 PM CDT, a severe thunderstorm was located over Mahtomedi, or
  11 miles northeast of St. Paul, moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Law enforcement reported trees down across the west metro.

  IMPACT...Expect damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Stillwater and Bayport around 825 PM CDT.
  Hudson and North Hudson around 830 PM CDT.
  Somerset around 835 PM CDT.
  New Richmond around 845 PM CDT.
  Star Prairie around 850 PM CDT.

Other locations impacted by this severe thunderstorm include
Otisville, Grant, Lake St Croix Beach, Willernie, Lakeland Shores,
Boardman, Huntington, William OBrien State Park, Willow River State
Park and St Marys Point.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4530 9238 4487 9240 4488 9302 4489 9301
      4489 9299 4512 9298 4513 9302 4529 9302
      4529 9280 4531 9273
TIME...MOT...LOC 0113Z 263DEG 35KT 4508 9297 

HAIL...<.75IN
WIND...60MPH
 
$$

JRB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 8:50 PM CDTSevere Thunderstorm WarningMPXBarron, Dunn, Polk, Saint Croix40 min
Aug 14, 9:01 PM CDTSevere Thunderstorm WarningMPXPierce, Saint Croix44 min
Aug 14, 9:29 PM CDTSevere Thunderstorm WarningMPXChippewa, Dunn31 min
Aug 14, 9:34 PM CDTSpecial Weather StatementMPXPepin56 min
Aug 14, 9:36 PM CDTSpecial Weather StatementMPXBarron, Rusk54 min
Aug 14, 10:01 PM CDTSpecial Weather StatementMPXChippewa, Dunn44 min
Aug 14, 10:35 PM CDTSpecial Weather StatementMPXEau Claire40 min
Aug 14, 7:01 PM CDTSevere Thunderstorm WarningMPXHennepin, Wright29 min
Aug 14, 7:11 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Nicollet, Scott, Sibley34 min
Aug 14, 7:14 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod, Wright31 min
Aug 14, 7:33 PM CDTSevere Thunderstorm WarningMPXCarver, Hennepin27 min
Aug 14, 7:50 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin, Ramsey55 min
Aug 14, 7:56 PM CDTTornado WarningMPXAnoka, Hennepin9 min
Aug 14, 8:12 PM CDTSevere Thunderstorm WarningMPXDakota, Le Sueur, Rice, Scott33 min
Aug 14, 8:16 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Washington44 min
Aug 14, 8:25 PM CDTSevere Thunderstorm WarningMPXDakota, Goodhue50 min
Aug 14, 9:17 PM CDTSpecial Weather StatementMPXGoodhue43 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2020Severe Thunderstorm Warnings in Minnesota, 2020Every severe thunderstorm warning in 2020

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.