Alert archive / Wisconsin / Special Weather Statements in 2021

Special Weather Statement, NWS Milwaukee, WI

October 10, 2021Waukesha County, Wisconsin

NWS Milwaukee, WI issued this special weather statement at Oct 10, 2021, 8:30 AM CDT for Waukesha County, Wisconsin. It was in force for 45 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
Oct 10, 2021, 8:30 AM CDT (13:30 UTC)
Expired
Oct 10, 2021, 9:15 AM CDT
In force
45 min
Issued by
NWS Milwaukee, WI
Hail
0.00 in
Wind
50

County Waukesha County, WI

The radar

The Milwaukee radar (KMKX), 14 km from the middle of the area, began a volume at 13:33 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

Green Bay/Straub, WI (KGRB), launched 12:00Z, 1.5 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, Green Bay/Straub, WI at 12:00Z on 2021-10-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 559 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, Green Bay/Straub, WI at 12:00Z on 2021-10-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 130 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
559 J/kg
Mixed-layer CIN
-163 J/kg
Mixed-layer LCL
987 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
130 m²/s²
0-3 km storm-relative helicity
185 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted.

236 
WWUS83 KMKX 101330
SPSMKX

Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
830 AM CDT Sun Oct 10 2021
 
WIZ059-064>066-070>072-101415-
Walworth WI-Waukesha WI-Milwaukee WI-Racine WI-Washington WI-
Jefferson WI-Kenosha WI-
830 AM CDT Sun Oct 10 2021

...Strong thunderstorms will impact portions of southwestern
Milwaukee, northeastern Walworth, Racine, Waukesha, southwestern
Washington, northeastern Jefferson and northwestern Kenosha Counties
through 915 AM CDT...

At 829 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles east of Johnson Creek to North Prairie
to 6 miles north of Lake Geneva. Movement was northeast at 45 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

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

Locations impacted include...
Northern Milwaukee, Waukesha, West Allis, Wauwatosa, New Berlin,
Brookfield, Greenfield, Menomonee Falls, Muskego, Greendale,
Pewaukee, Sussex, Hartland, Hales Corners, Lake Geneva, Mukwonago,
Delafield, Jackson, Elm Grove and Union Grove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4289 8852 4309 8880 4320 8853 4320 8842
      4324 8842 4333 8819 4308 8799 4261 8797
      4257 8847
TIME...MOT...LOC 1329Z 240DEG 40KT 4308 8865 4293 8844 4268 8840 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

$$

DDV

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 10, 6:21 AM CDTSpecial Weather StatementMKXLafayette39 min
Oct 10, 7:07 AM CDTSpecial Weather StatementMKXGreen23 min
Oct 10, 7:30 AM CDTSpecial Weather StatementMKXRock30 min
Oct 10, 7:50 AM CDTSpecial Weather StatementMKXWalworth25 min
Oct 10, 8:01 AM CDTSpecial Weather StatementMKXJefferson29 min

Nearby

Special Weather Statements in Wisconsin, 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.