Alert archive / Wisconsin / Special Weather Statements in 2021

Special Weather Statement, NWS La Crosse, WI

August 21, 2021La Crosse County, Wisconsin; Houston County, Minnesota

NWS La Crosse, WI issued this special weather statement at Aug 21, 2021, 12:39 AM CDT for La Crosse County, Wisconsin; Houston County, Minnesota. It was in force for 51 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, 2021, 12:39 AM CDT (05:39 UTC)
Expired
Aug 21, 2021, 1:30 AM CDT
In force
51 min
Issued by
NWS La Crosse, WI
Hail
0.00 in
Wind
30

Counties Houston County, MN, La Crosse County, WI

The radar

The La Crosse radar (KARX), 16 km from the middle of the area, began a volume at 05:41 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 nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 5.7 hours before the alert went out and 207 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 2021-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 395 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 2021-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 233 square meters per square second.19395878Sfc1 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
395 J/kg
Mixed-layer CIN
-100 J/kg
Mixed-layer LCL
1368 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
233 m²/s²
0-3 km storm-relative helicity
303 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.4

Open this sounding in Storm Lab

The text

As transmitted.

184 
WWUS83 KARX 210539
SPSARX

Special Weather Statement
National Weather Service La Crosse WI
1239 AM CDT Sat Aug 21 2021
 
IAZ010-011-MNZ088-095-096-WIZ041-053-210630-
Winneshiek IA-Allamakee IA-Fillmore MN-Winona MN-Houston MN-
Vernon WI-La Crosse WI-
1239 AM CDT Sat Aug 21 2021

...Strong thunderstorms will impact parts of northeast 
Iowa...southeast Minnesota...and west-central Wisconsin 
through 130 AM CDT...

At 1237 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 9 miles northeast of Canton to near Mabel to 6
miles southeast of Decorah. Movement was northeast at 40 mph.

HAZARD...Winds in excess of 30 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Strong thunderstorms will be near...
  Spring Grove around 1250 AM CDT.
  Rushford around 1255 AM CDT.
  Caledonia and Houston around 100 AM CDT.
  Hokah, New Albin and Brownsville around 115 AM CDT.
  Dakota around 120 AM CDT.
  La Crescent and Brice Prairie around 125 AM CDT.
  La Crosse, Onalaska, Holmen, West Salem, Stoddard, French Island 
  and La Crosse Airport around 130 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

&&

LAT...LON 4343 9173 4366 9190 4402 9153 4400 9144
      4398 9142 4398 9133 4399 9132 4402 9134
      4403 9134 4407 9131 4406 9128 4407 9127
      4405 9122 4409 9119 4409 9117 4407 9115
      4407 9102 4404 9100 4367 9097 4314 9170
TIME...MOT...LOC 0537Z 220DEG 36KT 4363 9182 4347 9170 4325 9168 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...30 MPH

$$

JSB

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 10:27 PM CDTSpecial Weather StatementARXBuffalo48 min
Aug 20, 10:43 PM CDTSpecial Weather StatementARXBuffalo62 min
Aug 20, 11:26 PM CDTSpecial Weather StatementARXBuffalo64 min
Aug 20, 11:05 PM CDTSpecial Weather StatementARXChickasaw, Howard, Winneshiek55 min
Aug 20, 11:56 PM CDTSpecial Weather StatementARXHoward, Winneshiek64 min

Nearby

Special Weather Statements in Wisconsin, 2021Special Weather Statements in Minnesota, 2021Every special weather statement in 2021

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.