Alert archive / Wisconsin / Special Weather Statements in 2021

Special Weather Statement, NWS Milwaukee, WI

August 7, 2021Waukesha County, Wisconsin

NWS Milwaukee, WI issued this special weather statement at Aug 7, 2021, 7:20 PM CDT for Waukesha County, Wisconsin. It was in force for 25 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 7, 2021, 7:20 PM CDT (00:20 UTC)
Expired
Aug 7, 2021, 7:45 PM CDT
In force
25 min
Issued by
NWS Milwaukee, WI
Hail
0.00 in
Wind
30

County Waukesha County, WI

The radar

The Milwaukee radar (KMKX), 21 km from the middle of the area, began a volume at 00:20 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.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 0.3 hours before the alert went out and 166 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 00:00Z on 2021-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 22 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Green Bay/Straub, WI at 00:00Z on 2021-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 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
22 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
1055 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
275 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

455 
WWUS83 KMKX 080020
SPSMKX

Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
720 PM CDT Sat Aug 7 2021
 
WIZ065-080045-
Waukesha WI-
720 PM CDT Sat Aug 7 2021

...Strong thunderstorms will impact portions of Waukesha County
through 745 PM CDT...

At 720 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Watertown to 6 miles southeast of Johnson
Creek to near Jefferson. Movement was east at 35 mph.

HAZARD...Winds of 30 to 40 mph.

SOURCE...Radar indicated.

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

Locations impacted include...
Waukesha, New Berlin, Brookfield, Menomonee Falls, Muskego, Pewaukee,
Sussex, Hartland, Mukwonago, Delafield, Wales, Okauchee Lake,
Oconomowoc, Lisbon, Vernon, Ottawa, Merton, Dousman, North Prairie
and Big Bend.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
southeastern Wisconsin.

&&

LAT...LON 4294 8813 4284 8834 4284 8854 4320 8854
      4319 8811
TIME...MOT...LOC 0020Z 280DEG 30KT 4316 8866 4302 8866 4296 8879 

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

$$

CMILLER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 7:00 PM CDTSpecial Weather StatementMKXRock30 min
Aug 7, 7:32 PM CDTSpecial Weather StatementMKXWalworth58 min
Aug 7, 7:51 PM CDTSpecial Weather StatementMKXMilwaukee, Waukesha54 min
Aug 7, 8:06 PM CDTSpecial Weather StatementMKXRacine, Walworth69 min
Aug 7, 9:13 PM CDTSpecial Weather StatementMKXGreen Lake, Marquette77 min
Aug 7, 10:01 PM CDTSpecial Weather StatementMKXDodge, Fond du Lac, Washington59 min
Aug 7, 10:22 PM CDTAreal Flood AdvisoryMKXFond du Lac, Green Lake, Marquette3 hr
Aug 7, 10:33 PM CDTSpecial Weather StatementMKXOzaukee, Sheboygan57 min
Aug 7, 11:00 PM CDTSpecial Weather StatementMKXWashington60 min
Aug 7, 11:36 PM CDTAreal Flood AdvisoryMKXDodge, Ozaukee, Washington75 min
Aug 7, 11:56 PM CDTSpecial Weather StatementMKXDodge34 min
Aug 8, 12:49 AM CDTAreal Flood WarningMKXDodge, Ozaukee, Washington6 hr
Aug 8, 12:56 AM CDTRiver Flood WarningMKXFond du Lac11 hr
Aug 8, 1:37 AM CDTAreal Flood WarningMKXMilwaukee, Ozaukee, Washington, Waukesha5 hr
Aug 8, 2:19 AM CDTFlash Flood WarningMKXMilwaukee, Ozaukee3 hr
Aug 8, 2:43 AM CDTFlash Flood WatchMKXColumbia, Dodge, Fond du Lac, Green Lake, Marquette, Milwaukee and 3 more17 hr
Aug 8, 9:54 AM CDTSmall Craft AdvisoryMKX10 hr
Aug 8, 4:24 PM CDTSevere Thunderstorm WarningMKXGreen Lake, Marquette36 min
Aug 8, 4:38 PM CDTSpecial Weather StatementMKXDodge37 min
Aug 8, 4:50 PM CDTSevere Thunderstorm WarningMKXWashington25 min
Aug 8, 5:05 PM CDTSpecial Marine WarningMKX24 min
Aug 8, 5:12 PM CDTSpecial Weather StatementMKXWashington33 min
Aug 8, 5:37 PM CDTSpecial Weather StatementMKXSheboygan23 min
Aug 8, 5:45 PM CDTSevere Thunderstorm WarningMKXSheboygan30 min
Aug 8, 6:09 PM CDTSpecial Marine WarningMKX51 min
Aug 8, 6:50 PM CDTSpecial Marine WarningMKX55 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.