Alert archive / Minnesota / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 119, NWS Twin Cities, MN

August 4, 2018Chisago County, Washington County, Minnesota; Polk County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 4, 2018, 12:17 AM CDT for Chisago County, Washington County, Minnesota; Polk County, Wisconsin. It was in force for 28 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 4, 2018, 12:17 AM CDT (05:17 UTC)
Expired
Aug 4, 2018, 12:45 AM CDT
In force
28 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Chisago County, MN, Washington County, MN, Polk County, WI

The radar

The Minneapolis radar (KMPX), 83 km from the middle of the area, began a volume at 05:20 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 4, 12:22 AM CDTHAIL 1Osceola, WI

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 5.3 hours before the alert went out and 85 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 2018-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3195 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 2018-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 164 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
3195 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
1086 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
164 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
3.0
Supercell composite
17.5

Open this sounding in Storm Lab

The text

As transmitted.

370 
WUUS53 KMPX 040517
SVRMPX
MNC025-163-WIC095-040545-
/O.NEW.KMPX.SV.W.0119.180804T0517Z-180804T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
1217 AM CDT SAT AUG 4 2018

The National Weather Service in The Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Southeastern Chisago County in east central Minnesota...
  Northeastern Washington County in east central Minnesota...
  South central Polk County in northwestern Wisconsin...

* Until 1245 AM CDT.

* At 1217 AM CDT, a severe thunderstorm was located over East
  Farmington, or 29 miles north of River Falls, moving east at 25
  mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Scandia, Osceola, St. Croix Falls, Dresser, Otisville, East
  Farmington, Osceola Airport, Nye and William OBrien State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4521 9280 4530 9286 4542 9256 4523 9247
TIME...MOT...LOC 0517Z 250DEG 22KT 4527 9273 

HAIL...1.00IN
WIND...<50MPH
 
$$
AMK
2 follow-up statements
167 
WWUS53 KMPX 040532
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
1232 AM CDT SAT AUG 4 2018

MNC025-163-040542-
/O.CAN.KMPX.SV.W.0119.000000T0000Z-180804T0545Z/
Chisago MN-Washington MN-
1232 AM CDT SAT AUG 4 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHISAGO AND
NORTHEASTERN WASHINGTON COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4523 9265 4534 9269 4542 9256 4523 9247
TIME...MOT...LOC 0532Z 250DEG 22KT 4530 9260 

$$

WIC095-040545-
/O.CON.KMPX.SV.W.0119.000000T0000Z-180804T0545Z/
Polk WI-
1232 AM CDT SAT AUG 4 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 AM CDT
FOR SOUTH CENTRAL POLK COUNTY...

At 1232 AM CDT, a severe thunderstorm was located over Nye, or 30
miles north of River Falls, moving east at 25 mph.

HAZARD...Half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Osceola, Dresser and Nye. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4523 9265 4534 9269 4542 9256 4523 9247
TIME...MOT...LOC 0532Z 250DEG 22KT 4530 9260 

HAIL...1.25IN
WIND...<50MPH
 
$$

AMK
226 
WWUS53 KMPX 040544
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
1244 AM CDT SAT AUG 4 2018

WIC095-040554-
/O.EXP.KMPX.SV.W.0119.000000T0000Z-180804T0545Z/
Polk WI-
1244 AM CDT SAT AUG 4 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL POLK COUNTY WILL
EXPIRE AT 1245 AM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However small hail
is still possible with this thunderstorm.

LAT...LON 4523 9265 4534 9269 4542 9256 4523 9247
TIME...MOT...LOC 0544Z 250DEG 22KT 4532 9251 

$$

AMK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 7:02 PM CDTSevere Thunderstorm WarningMPXStearns, Wright43 min
Aug 3, 7:33 PM CDTSevere Thunderstorm WarningMPXBenton, Mille Lacs, Sherburne, Wright27 min
Aug 3, 7:41 PM CDTSpecial Weather StatementMPXRenville49 min
Aug 3, 10:19 PM CDTFlash Flood WarningMPXBenton, Sherburne, Stearns3 hr
Aug 4, 12:05 AM CDTSpecial Weather StatementMPXIsanti25 min
Aug 4, 12:41 AM CDTSpecial Weather StatementMPXMille Lacs34 min
Aug 4, 12:43 AM CDTSpecial Weather StatementMPXIsanti32 min
Aug 4, 1:15 AM CDTSpecial Weather StatementMPXKanabec30 min
Aug 4, 12:58 AM CDTSpecial Weather StatementMPXPolk32 min
Aug 4, 1:49 AM CDTSpecial Weather StatementMPXBarron26 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2018Severe Thunderstorm Warnings in Wisconsin, 2018Every severe thunderstorm warning in 2018

Sources

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