Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 19, NWS Milwaukee, WI

May 6, 2012Jefferson County, Rock County, Walworth County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at May 6, 2012, 9:54 AM CDT for Jefferson County, Rock County, Walworth County, Wisconsin. It was in force for 36 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
May 6, 2012, 9:54 AM CDT (14:54 UTC)
Expired
May 6, 2012, 10:30 AM CDT
In force
36 min
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Jefferson County, WI, Rock County, WI, Walworth County, WI

The radar

The Milwaukee radar (KMKX), 32 km from the middle of the area, began a volume at 14:55 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
May 6, 9:57 AM CDTHAIL 1Sw Janesville, WION THE SOUTHWEST SIDE OF TOWN. ALSO...MINOR STREET FLOODING ABOUT THE DEPTH OF THE CURB.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 2.9 hours before the alert went out and 187 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, Davenport, at 12:00Z on 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2361 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, Davenport, at 12:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 181 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
2361 J/kg
Mixed-layer CIN
-82 J/kg
Mixed-layer LCL
571 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
181 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
9.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

948 
WUUS53 KMKX 061454
SVRMKX
WIC055-105-127-061530-
/O.NEW.KMKX.SV.W.0019.120506T1454Z-120506T1530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
954 AM CDT SUN MAY 6 2012

THE NATIONAL WEATHER SERVICE IN SULLIVAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL JEFFERSON COUNTY IN SOUTHEAST WISCONSIN...
  EASTERN ROCK COUNTY IN SOUTH CENTRAL WISCONSIN...
  NORTHWESTERN WALWORTH COUNTY IN SOUTHEAST WISCONSIN...

* UNTIL 1030 AM CDT

* AT 951 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR DOWNTOWN JANESVILLE...AND MOVING NORTHEAST
  AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  MILTON AROUND 1005 AM CDT.
  WHITEWATER AROUND 1025 AM CDT.

OTHER LOCATIONS IMPACTED BY THIS SEVERE THUNDERSTORM INCLUDE EMERALD
GROVE AND JOHNSTOWN CENTER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4293 8877 4280 8861 4257 8902 4273 8915
TIME...MOT...LOC 1454Z 230DEG 29KT 4269 8900
WIND...HAIL <50MPH 1.00IN

$$
3 follow-up statements
415 
WWUS53 KMKX 061502
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1002 AM CDT SUN MAY 6 2012

WIC055-105-127-061530-
/O.CON.KMKX.SV.W.0019.000000T0000Z-120506T1530Z/
JEFFERSON WI-WALWORTH WI-ROCK WI-
1002 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN
ROCK...NORTHWESTERN WALWORTH AND SOUTH CENTRAL JEFFERSON COUNTIES
UNTIL 1030 AM CDT...

AT 1000 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED NEAR MILTON...MOVING NORTHEAST AT 35 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  WHITEWATER AROUND 1025 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4259 8899 4277 8903 4293 8877 4280 8861
TIME...MOT...LOC 1502Z 230DEG 29KT 4273 8893
WIND...HAIL <50MPH 1.00IN

$$
MBK
413 
WWUS53 KMKX 061519
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1019 AM CDT SUN MAY 6 2012

WIC055-105-127-061530-
/O.CON.KMKX.SV.W.0019.000000T0000Z-120506T1530Z/
JEFFERSON WI-WALWORTH WI-ROCK WI-
1019 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN
ROCK...NORTHWESTERN WALWORTH AND SOUTH CENTRAL JEFFERSON COUNTIES
UNTIL 1030 AM CDT...

AT 1014 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED 5 MILES EAST OF MILTON...MOVING NORTHEAST AT 35
MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  WHITEWATER AROUND 1025 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4259 8899 4281 8892 4293 8877 4280 8861
TIME...MOT...LOC 1519Z 230DEG 29KT 4280 8880
WIND...HAIL <50MPH 1.00IN

$$

MBK
064 
WWUS53 KMKX 061528
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1028 AM CDT SUN MAY 6 2012

WIC055-105-127-061537-
/O.EXP.KMKX.SV.W.0019.000000T0000Z-120506T1530Z/
JEFFERSON WI-WALWORTH WI-ROCK WI-
1028 AM CDT SUN MAY 6 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN ROCK...
NORTHWESTERN WALWORTH AND SOUTH CENTRAL JEFFERSON COUNTIES WILL
EXPIRE AT 1030 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
HOWEVER HAIL TO ONE HALF INCH AND GUSTY WINDS OF 25 TO 35 MPH ARE 
STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 4259 8899 4281 8892 4293 8877 4280 8861
TIME...MOT...LOC 1527Z 230DEG 29KT 4284 8873

$$

MBK

The office that day

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

IssuedProductOfficeCountiesLasted
May 6, 7:52 AM CDTSevere Thunderstorm WarningMKXMarquette24 min
May 6, 8:29 AM CDTSevere Thunderstorm WarningMKXColumbia, Green Lake, Marquette31 min
May 6, 9:10 AM CDTSevere Thunderstorm WarningMKXColumbia, Dodge, Fond du Lac, Green Lake30 min
May 6, 9:32 AM CDTSevere Thunderstorm WarningMKXDane, Jefferson, Rock28 min
May 6, 10:12 AM CDTSevere Thunderstorm WarningMKXJefferson33 min
May 6, 12:22 PM CDTSevere Thunderstorm WarningMKXKenosha, Milwaukee, Racine, Walworth, Waukesha23 min
May 6, 12:27 PM CDTSpecial Marine WarningMKX40 min
May 6, 6:00 PM CDTSevere Thunderstorm WarningMKXWalworth30 min
May 6, 6:46 PM CDTSevere Thunderstorm WarningMKXRacine, Walworth29 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2012Every severe thunderstorm warning in 2012

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.