Severe Thunderstorm Warning #2 - Southern Wisconsin

WUUS53 KMKX 252201
SVRMKX
WIC079-089-131-252230-
/O.NEW.KMKX.SV.W.0002.160425T2201Z-160425T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
501 PM CDT MON APR 25 2016

THE NATIONAL WEATHER SERVICE IN SULLIVAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN WASHINGTON COUNTY IN SOUTHEASTERN WISCONSIN...
  OZAUKEE COUNTY IN SOUTHEASTERN WISCONSIN...
  NORTHERN MILWAUKEE COUNTY IN SOUTHEASTERN WISCONSIN...

* UNTIL 530 PM CDT

* AT 501 PM CDT...DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM SLINGER TO NEAR MERTON...AND MOVING EAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WEST BEND...MEQUON...HARTFORD...GRAFTON...CEDARBURG...PORT WASHINGTON...
  JACKSON...SLINGER...SAUKVILLE...THIENSVILLE...BELGIUM...FREDONIA...NEWBURG...GERMANTOWN...RICHFIELD...HUBERTUS...SAINT LAWRENCE...HOLY HILL...HARRINGTON BEACH ST PARK AND WAUBEKA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...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 4338 8787 4330 8789 4326 8791 4321 8790
      4319 8823 4319 8840 4337 8834 4354 8780
      4349 8779
TIME...MOT...LOC 2201Z 252DEG 36KT 4333 8829 4322 8836

$$

BMS

Issued Severe Thunderstorm Warning for BOTH cells indicated above. Severe Probs for nothern cell was 23% with 0.67 MESH and Severe Probs for southern cell was 17% with 0.31 MESH.

KMKZ Radar is indicating that 65 DBZ to 25K feet for the northern cell in Washington County. Southern cell 59 DBZ to 23K feet. Felt with a hail spike that it was prudent to issue Severe Thunderstorm Warning for both cells, rather than just the northern cell and Significant Weather Advisory the southern cell.

 
































WWUS53 KMKX 252215
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
514 PM CDT MON APR 25 2016

WIC079-252224-
/O.CAN.KMKX.SV.W.0002.000000T0000Z-160425T2230Z/
MILWAUKEE WI-
514 PM CDT MON APR 25 2016

...THE SEVERE THUNDERSTORM WARNING FOR MILWAUKEE COUNTY IS
CANCELLED...

THE STORMS WHICH PROMPTED THE WARNING HAVE MOVED OUT OF THE WARNEDAREA. THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 4338 8787 4330 8789 4326 8791 4321 8790
      4320 8823 4321 8828 4339 8823 4354 8780
      4349 8779
TIME...MOT...LOC 2214Z 252DEG 36KT 4337 8814 4326 8821

$$

WIC089-131-252230-
/O.CON.KMKX.SV.W.0002.000000T0000Z-160425T2230Z/
WASHINGTON WI-OZAUKEE WI-
514 PM CDT MON APR 25 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM CDT
FOR SOUTHEASTERN WASHINGTON AND OZAUKEE COUNTIES...

AT 514 PM CDT...DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO GOLF BALL SIZE AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM NEAR JACKSON TO 6 MILES SOUTHEAST OF SLINGER...MOVING EAST AT 40 MPH.

LOCATIONS IMPACTED INCLUDE...
WEST BEND...MEQUON...GRAFTON...CEDARBURG...PORT WASHINGTON...JACKSON...SLINGER...SAUKVILLE...THIENSVILLE...BELGIUM...FREDONIA...NEWBURG...
GERMANTOWN...RICHFIELD...HUBERTUS AND HARRINGTON BEACH ST PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THESE STORMS...PREPARE IMMEDIATELY FOR LARGE HAIL AND DEADLY CLOUD TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE OFFICE IN SULLIVAN.

&&

LAT...LON 4338 8787 4330 8789 4326 8791 4321 8790
      4320 8823 4321 8828 4339 8823 4354 8780
      4349 8779
TIME...MOT...LOC 2214Z 252DEG 36KT 4337 8814 4326 8821

$$

BMS

Updated Severe Thunderstorm Warning to remove Milwaukee County and keep others, as we are seeing an increase in the Prob Severe to 83% with MESH at 0.95". NWS MKX has indicated that Golf Ball Sized hail has been confirmed 2 ESE Slinger at 17:08 CDT. This storm has 65 DBZ to 22K feet. Increase hail size of warning to match to Golf Ball Sized hail.

VERIFICATION INFORMATION: 
Golf Ball Sized Hail (1.75") reported at 17:08 CDT - 7 Minute Warning Lead Time
Quarter Sized Hail (1.00")  reported at 17:00 CDT - No lead time gained, missed by two minutes.
Penny Sized Hail (0.75") reported at 17:22 CDT - 21 Minute Warning Lead Time

Forecaster: Schuerman

SPS Issued for Far NE Illinois

Initial storm warned for after ProbSvr topped out at 82 percent only generated pea sized hail before weakening again. The second storm of interest topped out at 61 percent on ProbSvr. Like the first cell, this storm initially peaked and slowly weakend in a multi-storm cluster environment. Due to the close proximity of nearby cells, the Lightning Jump parameters were not as useful.

Update: A delayed report of quarter sized hail arrived for this storm plus another that verfied the first warning.  This increased confidence in the use of ProbSVR for values that was 70 percent or greater.  This storm moved offshore with values that dipped slightly after producing the quarter sized hail report, but then picked up again with values consistently exceeding 70 percent.  The delay of reports received contaminated our decision making and reduced lead times on storms up this point.

Forecaster: Manbearpig

Significant Weather Advisory #3 Issued - Southern Wisconsin

WWUS83 KMKX 252148
SPSMKX

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
448 PM CDT MON APR 25 2016

WIZ071-072-252230-
KENOSHA WI-RACINE WI-
448 PM CDT MON APR 25 2016

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL RACINE AND KENOSHA COUNTIES UNTIL 530 PM CDT...

AT 448 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM OVER CAMP LAKE...MOVING NORTHEAST AT 55 MPH.

HALF INCH HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
KENOSHA...RACINE...MOUNT PLEASANT...PLEASANT PRAIRIE...STURTEVANT...PADDOCK LAKE...CAMP LAKE...SILVER LAKE...SALEM...BRISTOL...ELMWOOD PARK AND NORTH BAY.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 4256 8822 4277 8777 4271 8777 4267 8779
      4266 8781 4261 8782 4259 8781 4253 8782
      4249 8792 4250 8818
TIME...MOT...LOC 2148Z 244DEG 47KT 4255 8812

$$

BMS

Significant Weather Advisory issued for this storm for half inch hail and winds above 40 MPH. MESH is at 0.53" and KMKZ radar supports some small hail with this thunderstorm.

Forecaster: Schuermamn

First Warning Near Rockford

We've been monitoring a storm near Rockford, Illinois that has been gradually increasing in intensity. Initially, we noticed that in the reflectivity core, echos were near 60 dBZ at roughly the -20C level according to the NUCAPS profile. The ProbSevere was also gradually increasing from 15-50% before jumping to 70%. The jump to 70% pushed us over the edge on the Severe Warning decision.

Other than the ProbSevere, none of the GOES-R/total lightning products were indicative of severe weather.

---UPDATE---

This warning ended up verifying with a 1" hail report in northern McHenry county. Unfortunately, this report was about an hour delayed, and we were under the assumption that this warning was a false alarm. With that assumption, we did not warn on similar storms later in the day, one of which did produce 1" hail near Lake Michigan.

-Toki Wartooth

Convective Initiation & Radar Correlation - Southern Wisconsin

Monday 25 April 2016 - 16:30 - Mesoscale Discussion Update

Concerning: Severe Thunderstorm Potential - Southern Wisconsin

Thunderstorms have continued to develop over Southern Wisconsin, and what has been noted with this, the Convective Initiation Probability (CI) has correllated well with where the thunderstorms have developed ths afternoon/

Left: Convective Initation Probability (CI Probability)
Right: KMKX Radar with Severe Warnings & Prob Severe Model

Notice how the highest areas for convective initiation (Orange/Left) correllates very well with where thunderstorms have developed over the past hour, while the Severe Convective Probability (Severe CI) remains low over the forecasted area.

Forecaster: Schuerman

NUCAPS Showing Enhanced Instability Compared To Mesoanalysis

The NUCAPS temperature and moisture profile (above) is showing slightly higher instability than the mesoanalysis. After adjusting the surface temperature and dew point on the NUCAPS profile, there was approximately 1700 j/kg of SBCAPE compared to roughly 1000 j/kg on the meso analysis. Unfortunately, the MLCAPE on the NUCAPS profile was unrealistically low at around 150 j/kg, but I'm guessing this has to do with poor performance in the boundary layer.

A few cells have begun to initiate in Northern Illinois, but there appears to still be a bit of a cap in place despite the fact that the mesoanalysis is showing an uncapped atmosphere. The cap will likely erode completely in the next couple of hours and when that happens, storm intensity and coverage will increase rapidly.

-Toki Wartooth

Severe Thunderstorm Warning #1 - Southern Wisconsin

WUUS53 KMKX 252055
SVRMKX
WIC089-117-131-252130-
/O.NEW.KMKX.SV.W.0001.160425T2055Z-160425T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
355 PM CDT MON APR 25 2016

THE NATIONAL WEATHER SERVICE IN SULLIVAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN WASHINGTON COUNTY IN SOUTHEASTERN   WISCONSIN...
  SOUTH CENTRAL SHEBOYGAN COUNTY IN EAST CENTRAL WISCONSIN...
  NORTHERN OZAUKEE COUNTY IN SOUTHEASTERN WISCONSIN...

* UNTIL 430 PM CDT

* AT 355 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR WEST BEND...AND MOVING NORTHEAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WEST BEND...PORT WASHINGTON...SAUKVILLE...BELGIUM...FREDONIA...CEDAR GROVE...RANDOM LAKE...NEWBURG...ADELL...HINGHAM...FILLMORE...SILVER CREEK...BOLTONVILLE AND WAUBEKA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...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 4346 8780 4341 8785 4334 8825 4340 8833
      4368 8788 4355 8779
TIME...MOT...LOC 2055Z 241DEG 33KT 4340 8824

$$

BMS/BAJ

Issued Severe Thunderstorm Warning for this cell in Southern Wisconsin, went above 40% Prob Severe with above 0.70 MESH, KMKZ indicated 66 DBZ to 22K feet with this thunderstorm, felt this was enough to pull a trigger for a Severe Thunderstorm Warning.

WWUS53 KMKX 252112
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
411 PM CDT MON APR 25 2016

WIC089-117-131-252130-
/O.CON.KMKX.SV.W.0001.000000T0000Z-160425T2130Z/
WASHINGTON WI-SHEBOYGAN WI-OZAUKEE WI-
411 PM CDT MON APR 25 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM CDT FOR NORTHEASTERN WASHINGTON...SOUTH CENTRAL SHEBOYGAN AND NORTHERN OZAUKEE COUNTIES...

AT 411 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED OVER NEWBURG... OR 7 MILES NORTHEAST OF WEST BEND...MOVING NORTHEAST AT 40 MPH.

LOCATIONS IMPACTED INCLUDE...BELGIUM...FREDONIA...CEDAR GROVE...RANDOM LAKE...NEWBURG...ADELL...HINGHAM...
FILLMORE...SILVER CREEK AND WAUBEKA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS CAN PRODUCE...DESTRUCTIVE HAIL...DEADLYLIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO ANINTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVYRAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATERCOVERS THE ROAD.

&&

LAT...LON 4340 8807 4348 8814 4367 8788 4355 8779
      4346 8780 4345 8781
TIME...MOT...LOC 2111Z 241DEG 33KT 4347 8806

$$

BMS/BAJ

Updated Severe Thunderstorm Warning to remove the wind threat with this thunderstorm but keep the hail threat, as we are seeming some spiking on the radar with this thunderstorm as it continues to move to the Northeast.

WWUS53 KMKX 252124
SVSMKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
424 PM CDT MON APR 25 2016

WIC089-117-131-252134-
/O.EXP.KMKX.SV.W.0001.000000T0000Z-160425T2130Z/
WASHINGTON WI-SHEBOYGAN WI-OZAUKEE WI-
424 PM CDT MON APR 25 2016

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN WASHINGTON...SOUTH CENTRAL SHEBOYGAN AND NORTHERN OZAUKEE COUNTIES WILL EXPIRE AT 430 PM CDT...
               
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY. THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE SULLIVAN.

LAT...LON 4340 8807 4348 8814 4367 8788 4355 8779
      4346 8780 4345 8781
TIME...MOT...LOC 2122Z 241DEG 33KT 4347 8806

$$

BMS/BAJ

Allowing Severe Thunderstorm Warning to expire as scheduled at 16:30. Thunderstorm has weakened below severe limits. Severe Prob is less than 10%, reflectivity is not supportive of keeping a new warning with this cell, therefore it will be allowed to expire.

VERIFICATION UPDATE: This Severe Thunderstorm Warning has verified. KMKX has reported 1.00" hail 2 SE West Bend, WI at 2101Z relayed through MPING. Lead Time for this Severe Thunderstorm Warning was 6 minutes.

Forecaster: Schuerman/Jackson

Second Significant Weather Advisory Issued - Southern Wisconsin

WWUS83 KMKX 252034
SPSMKX

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
333 PM CDT MON APR 25 2016

WIZ060-065-066-252115-
OZAUKEE WI-WAUKESHA WI-MILWAUKEE WI-
333 PM CDT MON APR 25 2016

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL OZAUKEE...
NORTHWESTERN MILWAUKEE AND NORTHEASTERN WAUKESHA COUNTIES UNTIL 415 PM CDT...

AT 333 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM OVER NORTHERN MILWAUKEE...MOVING NORTHEAST AT 30 MPH.

HALF INCH HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...NORTHERN MILWAUKEE...MENOMONEE FALLS...MEQUON...WHITEFISH BAY...BROWN DEER...FOX POINT...BAYSIDE...RIVER HILLS AND GLENDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD TO LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4314 8790 4312 8790 4309 8799 4318 8808
      4326 8791 4324 8791 4321 8790 4320 8790
      4316 8788
TIME...MOT...LOC 2033Z 238DEG 25KT 4318 8800

$$

BMS

Second Significant Weather Advisory issues for thunderstorm to the north of first Significant Weather Advisory. MESH is now over 0.50" with Prob Severe at 35%. Went for half inch sized hail and winds in excess of 40 MPH with these. Lightning being presented at 2.0 Sigma for these thunderstorms as they are heading off shore.

Forecaster: Schuerman

Cells Beginning to Form Over Northern, Western Illinois

Satellite Rapid Scan Operations is beginning to show a few towering cumulus forming along a weak frontal zone that extends from near Davenport, IA to Genoa City, WI. Low level shear and stability is knocking down most convection, but CAPE values are increasing from the southwest and are forecast to increase further over the next 2 hours by SPC mesoanalysis. Surface based lifted indices are now -8 near the brief cell over Western Illinois.

Forecaster: Manbearpig

Significant Weather Advisory Issued for Strong Thunderstorms - Southern Wisconsin

WWUS83 KMKX 252008
SPSMKX

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
307 PM CDT MON APR 25 2016

WIZ065-066-252045-
WAUKESHA WI-MILWAUKEE WI-
307 PM CDT MON APR 25 2016

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MILWAUKEE AND SOUTHEASTERN WAUKESHA COUNTIES UNTIL 345 PM CDT...

AT 307 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM OVER MUKWONAGO...MOVING NORTHEAST AT 30 MPH.

HALF INCH HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
MILWAUKEE...WAUKESHA...WEST ALLIS...WAUWATOSA...NEW BERLIN...BROOKFIELD...GREENFIELD...OAK CREEK...MUSKEGO...SOUTH MILWAUKEE...CUDAHY...GREENDALE...PEWAUKEE...ST. FRANCIS...HALES CORNERS...MUKWONAGO...ELM GROVE...WEST MILWAUKEE...NORTH PRAIRIE AND BUTLER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD TO LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4287 8832 4293 8839 4316 8799 4294 8784
      4292 8784
TIME...MOT...LOC 2007Z 244DEG 28KT 4291 8831

$$

BMS

Tracking the severe probability for this thunderstorm, we're into the 20% range now, with MESH 0.48", CAPE at 1039 J/kg, so decided to go with a Significant Weather Advisory for this area. Severe CI Probability is still remaining low, but CI Probability is much better, so not anticipating this storm going severe, but continuing to watch this thunderstorm cell.

Forecaster: Schuerman