Alert archive / Minnesota / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 204, NWS Twin Cities, MN

September 20, 2017Chisago County, Minnesota; Polk County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Sep 20, 2017, 3:04 AM CDT for Chisago County, Minnesota; Polk County, Wisconsin. It was in force for 26 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: Sep 20, 2017, 3:04 AM CDT (08:04 UTC)
Expired: Sep 20, 2017, 3:30 AM CDT
In force: 26 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Hail: 1.5 in
Wind: 50.0 mph

Counties Chisago County, MN, Polk County, WI

The radar

The Minneapolis radar (KMPX), 87 km from the middle of the area, began a volume at 08:08 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.

Issued	Product	Office	Lasted
Sep 20, 1:22 AM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 8.1 hours before the alert went out and 89 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 246 J/kg
Mixed-layer CIN: -155 J/kg
Mixed-layer LCL: 1179 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 274 m²/s²
0-3 km storm-relative helicity: 454 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.2

Open this sounding in Storm Lab

The text

As transmitted.

044 
WUUS53 KMPX 200804
SVRMPX
MNC025-WIC095-200830-
/O.NEW.KMPX.SV.W.0204.170920T0804Z-170920T0830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
304 AM CDT WED SEP 20 2017

The National Weather Service in The Twin Cities has issued a

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

* Until 330 AM CDT

* At 304 AM CDT, a severe thunderstorm was located near Chisago City,
  or 18 miles southeast of Cambridge, moving northeast at 50 mph.

  HAZARD...Ping pong ball size hail. 

  SOURCE...Radar indicated. 

  IMPACT...People and animals outdoors will be injured. Expect 
           damage to roofs, siding, windows, and vehicles. 

* This severe thunderstorm will remain over mainly rural areas of
  southeastern Chisago and northwestern Polk Counties, including the
  following locations: Wolf Creek, Branch, Cushing and Wild River
  State Park.

This includes the following highways...
 Interstate 35 between mile markers 139 and 145.
 U.S. Highway 8 in Minnesota between mile markers 7 and 16.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4530 9283 4538 9302 4544 9302 4564 9289
      4565 9253
TIME...MOT...LOC 0804Z 210DEG 44KT 4542 9289 

HAIL...1.50IN
WIND...<50MPH
 
$$

1 follow-up statement

462 
WWUS53 KMPX 200818
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
318 AM CDT WED SEP 20 2017

MNC025-WIC095-200830-
/O.CON.KMPX.SV.W.0204.000000T0000Z-170920T0830Z/
Chisago MN-Polk WI-
318 AM CDT WED SEP 20 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 AM CDT
FOR EAST CENTRAL CHISAGO AND NORTHWESTERN POLK COUNTIES...

At 318 AM CDT, a severe thunderstorm was located over Wolf Creek, or
24 miles southeast of Pine City, moving northeast at 50 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...
Cushing, Wolf Creek and Wild River State Park. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4539 9276 4555 9295 4564 9289 4565 9253
TIME...MOT...LOC 0818Z 218DEG 42KT 4552 9272 

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

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 19, 10:55 PM CDT	Severe Thunderstorm Warning	MPX	Lac qui Parle	50 min
Sep 19, 11:24 PM CDT	Severe Thunderstorm Warning	MPX	Stevens, Swift	36 min
Sep 19, 11:42 PM CDT	Special Weather Statement	MPX	Lac qui Parle, Yellow Medicine	48 min
Sep 19, 11:50 PM CDT	Severe Thunderstorm Warning	MPX	Douglas, Pope, Stevens	55 min
Sep 20, 12:03 AM CDT	Special Weather Statement	MPX	Swift	57 min
Sep 20, 12:06 AM CDT	Special Weather Statement	MPX	Meeker	24 min
Sep 20, 12:16 AM CDT	Special Weather Statement	MPX	Chippewa, Yellow Medicine	44 min
Sep 20, 12:24 AM CDT	Severe Thunderstorm Warning	MPX	Swift	21 min
Sep 20, 12:42 AM CDT	Severe Thunderstorm Warning	MPX	Kandiyohi, Pope, Stearns, Todd	33 min
Sep 20, 12:45 AM CDT	Special Weather Statement	MPX	Benton, Morrison	45 min
Sep 20, 12:51 AM CDT	Special Weather Statement	MPX	Kandiyohi, Meeker, Renville	39 min
Sep 20, 12:55 AM CDT	Special Weather Statement	MPX	Brown, Redwood	35 min
Sep 20, 1:02 AM CDT	Severe Thunderstorm Warning	MPX	Kandiyohi, Meeker, Renville	43 min
Sep 20, 1:11 AM CDT	Severe Thunderstorm Warning	MPX	Benton, Morrison, Sherburne, Stearns	49 min
Sep 20, 1:15 AM CDT	Severe Thunderstorm Warning	MPX	Brown, Nicollet, Redwood, Renville, Sibley	30 min
Sep 20, 1:37 AM CDT	Severe Thunderstorm Warning	MPX	Meeker, Sherburne, Stearns, Wright	38 min
Sep 20, 1:41 AM CDT	Severe Thunderstorm Warning	MPX	McLeod, Renville, Sibley	34 min
Sep 20, 1:49 AM CDT	Severe Thunderstorm Warning	MPX	Benton, Kanabec, Mille Lacs, Morrison	56 min
Sep 20, 2:00 AM CDT	Severe Thunderstorm Warning	MPX	Benton, Isanti, Mille Lacs, Sherburne	45 min
Sep 20, 2:12 AM CDT	Special Weather Statement	MPX	Anoka, Hennepin, Wright	48 min
Sep 20, 2:36 AM CDT	Special Weather Statement	MPX	Hennepin, Ramsey, Washington	69 min
Sep 20, 2:57 AM CDT	Special Weather Statement	MPX	Chisago	33 min
Sep 20, 3:26 AM CDT	Special Weather Statement	MPX	Polk	34 min
Sep 20, 4:26 AM CDT	Special Weather Statement	MPX	Chippewa, Dunn, Eau Claire, Pepin	79 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2017 Severe Thunderstorm Warnings in Wisconsin, 2017 Every severe thunderstorm warning in 2017

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.