Severe Thunderstorm Warning 69, NWS Green Bay, WI

198 
WWUS53 KGRB 250802
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
302 AM CDT Tue Aug 25 2020

WIC073-250845-
/O.CON.KGRB.SV.W.0069.000000T0000Z-200825T0845Z/
Marathon WI-
302 AM CDT Tue Aug 25 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM CDT
FOR SOUTHERN MARATHON COUNTY...

At 301 AM CDT, a severe thunderstorm was located 12 miles northeast
of Marshfield, or 20 miles southwest of Wausau, moving east at 40
mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Mosinee around 325 AM CDT.

Other locations impacted by this severe thunderstorm include Peplin,
Rozellville, Big Eau Pleine County Park, Moon, Rocky Corners, Halder,
Dancy, Knowlton, Evergreen and Stratford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

LAT...LON 4486 9006 4486 8945 4469 8947 4468 8994
      4468 9009
TIME...MOT...LOC 0801Z 271DEG 36KT 4477 8997 

HAIL...1.50IN
WIND...60MPH
 
$$

Eckberg

227 
WWUS53 KGRB 250816
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
316 AM CDT Tue Aug 25 2020

WIC073-250845-
/O.CON.KGRB.SV.W.0069.000000T0000Z-200825T0845Z/
Marathon WI-
316 AM CDT Tue Aug 25 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM CDT
FOR SOUTH CENTRAL MARATHON COUNTY...

At 315 AM CDT, a severe thunderstorm was located 7 miles southwest of
Mosinee, or 17 miles southwest of Wausau, moving east at 40 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  Mosinee around 325 AM CDT.

Other locations impacted by this severe thunderstorm include Big Eau
Pleine County Park, Dancy, Knowlton, Moon and Rocky Corners.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

LAT...LON 4477 8987 4478 8946 4469 8947 4468 8992
TIME...MOT...LOC 0815Z 271DEG 36KT 4473 8980 

HAIL...1.00IN
WIND...60MPH
 
$$

Eckberg

671 
WWUS53 KGRB 250827
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
327 AM CDT Tue Aug 25 2020

WIC073-250837-
/O.CAN.KGRB.SV.W.0069.000000T0000Z-200825T0845Z/
Marathon WI-
327 AM CDT Tue Aug 25 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MARATHON COUNTY
IS CANCELLED...
        
The storm which prompted the warning has weakened below severe 
limits. Therefore, the warning has been cancelled. However gusty 
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 4477 8987 4478 8946 4469 8947 4468 8992
TIME...MOT...LOC 0826Z 270DEG 39KT 4473 8961 

$$

Eckberg

Area Forecast Discussion
National Weather Service Green Bay WI
1142 PM CDT Mon Aug 24 2020

Updated aviation portion for 06Z TAF issuance

.SHORT TERM...Tonight and Tuesday
Issued at 225 PM CDT Mon Aug 24 2020

Main forecast issue centers around the anticipated convective
complex of thunderstorms that will move across central and east-
central WI tonight. Questions also linger on Tuesday regarding
potential for additional showers/storms that may develop during
the afternoon.

The 19Z MSAS surface analysis showed a cold front that stretched
from north-central WI southwest into southern MN. Weak high
pressure extended from northeast ND into northern MN. The radar
mosaic indicated scattered showers and thunderstorms that have
moved into west-central WI.

The cold front is forecast to slowly sag south into central WI
tonight and be the primary focus for showers and thunderstorms.
Despite a gradual loss of daytime heating, enough instability
(MUCAPES of 1K-2K J/KG) to be in place this evening along with
stronger shear of 35-45 knots, to produce strong to locally severe
storms generally along and south of Highway 29. Large hail and
damaging winds would be the primary threats. In addition, PW
values of 1.5-2.0 inches and dew points around 70 degrees ahead of
the front may produce very heavy rainfall with possible flooding
if thunderstorms train over the same area. The chance of showers/
storms over northern WI should dissipate overnight as the front
edges south. This may lead to fog development if enough breaks in
the clouds can occur. Min temperatures to range from the lower 50s
near the MI border (north-central WI), to the upper 60s across
east-central WI.

The cold front is forecast to stall between central and southern
WI on Tuesday and linger a chance of showers/few thunderstorms
over parts of central/east-central WI through morning hours. As
daytime heating takes place, cannot rule out a few showers/storms
to pop up again over parts of central/east-central WI. Areas north
of Highway 29 should see a decent amount of sunshine, less
humidity and slightly cooler temperatures. Look for max
temperatures to range from the upper 70s to around 80 degrees
north, lower to middle 80s south.

.LONG TERM...Tuesday Night Through Monday
Issued at 225 PM CDT Mon Aug 24 2020

Zonal flow will continue through the work week, with with a west
to east oriented frontal boundary lingering near the area. The air
mass will be very warm, moist and unstable, leading to several
periods of thunderstorm activity. Temperatures through this
period are expected to be much above normal through Thursday, but
daily readings will be dependent on the position of the frontal
boundary, any ongoing precipitation, and debris cloudiness from
overnight convection. Wednesday looks to to be the warmest day,
with highs reaching the lower 90s in central and east central WI.

The frontal boundary will lift north as a warm front Tuesday
night into Wednesday. Strong H8 WAA will become focused over
north/northeast WI overnight, and upper forcing with the RRQ of
an upper level jet will affect this same area. While isolated/
scattered convection may be found along the boundary in the
evening, the main activity is expected over the northeast half of
the CWA late Tuesday night into Wednesday morning, when the
dynamic forcing will be greatest. There are some timing differences,
with the GFS holding off any significant development until Wednesday
morning. Severe thunderstorms with large hail are possible, given
substantial elevated instability (H8 LI's -3 to -7 C) and strong
shear (bulk shear 40-50 kts, SRH 200-400). Heavy rainfall will
also be a concern, as PWATs will be in the 1.5 to 2 inch range.
The warm front may become stationary over northern WI later
Wednesday, leading to a continued threat of strong to severe
storms near the Upper Michigan border in the afternoon and evening.
Farther south, very warm mid-level temperatures (capping) should
suppress convective development.

The front will sag back to the south as a cold front later
Wednesday night into Thursday, and could result in another bout of
strong storms over the southern half of the CWA Thursday afternoon
and evening. The threat of showers and storms will continue until
a more significant Canadian cold front sweeps across the area
Friday night.

A cooler and drier Canadian air mass will return to the area for
the weekend, with temperatures near to a little below normal. As
the high shifts east early next week, southerly return flow will
bring the chance of precipitation back into the western Great
lakes region.
&&

.AVIATION...for 06Z TAF Issuance
Issued at 1141 PM CDT Mon Aug 24 2020

A cold front passing through northeast Wisconsin this evening,
will stall over central/southern WI on Tuesday. Expect scattered
showers and thunderstorms much of central and east-central
Wisconsin though the early morning hours. Gusty winds and large
hail are possible with the strongest storms. VFR conditions will
exist where no precipitation occurs. However, vsbys could quickly
drop to IFR under of the storms. Partial clearing skies will occur
late tonight across the north which has already led to patchy fog
development and visibilities dropping into the IFR/MVFR range
across north-central WI.

As long as the stalled front is in the vicinity, a few showers
and thunderstorms may develop throughout the day Tuesday, but
mainly in the afternoon hours. While VFR conditions to be most
prevalent, vsbys could drop into the MVFR category under any
precipitation. Additional chances of showers and storms will
linger into Tuesday night as the front lifts northward as a warm
front, again, some of those storms could become strong to severe
very late Tuesday night. This would be at the very end of this TAF
issuance.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM.....Kallas
LONG TERM......Kieckbusch
AVIATION.......Cooley

Hazardous Weather Outlook
National Weather Service Green Bay WI
232 PM CDT Mon Aug 24 2020

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-251945-
Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln-
Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano-
Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago-
Calumet-Manitowoc-Southern Marinette County-
Southern Oconto County-
232 PM CDT Mon Aug 24 2020

This Hazardous Weather Outlook is for north-central and northeast
Wisconsin.

.DAY ONE...Tonight

There is a slight risk of severe weather over mainly central and
east-central Wisconsin. Large hail, damaging winds and torrential
downpours will be possible.

.DAYS TWO THROUGH SEVEN...Tuesday through Monday

Thunderstorms will be possible at times through the work week.
Another severe threat may occur over north-central and northeast
Wisconsin Tuesday night into Wednesday. Large hail and heavy
rainfall will be the main threats.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed tonight. Spotters are asked to
report any hail, strong winds or rainfall over one inch.

LMZ521-522-541>543-251945-
The Bay of Green Bay south of a line from Cedar River MI to Rock
Island Passage-Lake Michigan from Washington Island to Sheboygan-
232 PM CDT Mon Aug 24 2020

This Hazardous Weather Outlook is for portions of northwest Lake
Michigan and the waters of Green Bay.

.DAY ONE...Tonight

Isolated strong to severe storms are possible late tonight,
mainly south of Sturgeon Bay. Gusty winds and hail are possible
with the strongest storms.

.DAYS TWO THROUGH SEVEN...Tuesday through Monday

Thunderstorms will be possible at times through the work week.
Another round of strong to severe storms will be possible Tuesday
night into Wednesday, especially north of Sturgeon Bay. Any
storms that develop will pose a hazard to boaters.

Kallas/Kieckbusch

Special Weather Statement
National Weather Service Green Bay WI
1119 PM CDT Mon Aug 24 2020

WIZ005-010>012-250730-
Vilas-Oneida-Forest-Florence-
1119 PM CDT Mon Aug 24 2020

...LOCALLY DENSE FOG EXPECTED OVERNIGHT INTO EARLY TUESDAY
MORNING...

Clearing skies and abundant low level moisture has led to some
patchy fog development across portions of north-central Wisconsin
late this evening. The fog is expected to expand overnight into
early Tuesday morning. The fog may become locally dense at times,
reducing visibility to one-quarter of a mile. The fog is expected
to quickly dissipate around sunrise.

If traveling overnight, be prepared for sudden changes in
visibility and be sure to allow extra time to reach your
destination.

Kurimski

Special Weather Statement
National Weather Service Green Bay WI
1136 PM CDT Mon Aug 24 2020

WIZ035-250530-
Wood WI-
1136 PM CDT Mon Aug 24 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN WOOD COUNTY UNTIL
1230 AM CDT...

At 1136 PM CDT, Doppler radar was tracking a strong thunderstorm 11
miles west of Babcock, or 18 miles southeast of Neillsville, moving
southeast at 20 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Babcock, Nekoosa, Port Edwards, Cranmoor, Sandhill Wildlife Area,
Scranton and Dexterville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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 4443 9032 4433 8986 4425 8991 4425 9032
TIME...MOT...LOC 0436Z 293DEG 18KT 4434 9036

MPC

Special Weather Statement
National Weather Service Green Bay WI
1225 AM CDT Tue Aug 25 2020

WIZ035-036-045-250615-
Wood WI-Waushara WI-Portage WI-
1225 AM CDT Tue Aug 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN WOOD...SOUTHWESTERN
PORTAGE AND WAUSHARA COUNTIES UNTIL 115 AM CDT...

At 1224 AM CDT, Doppler radar was tracking a strong thunderstorm near
New Rome, or 9 miles south of Wisconsin Rapids, moving southeast at
40 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Wisconsin Rapids, Wautoma, Redgranite, Pittsville, Plainfield,
Babcock, Lake Wazeecha, Nekoosa, Silver Lake and Port Edwards.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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 4460 9032 4405 8889 4399 8890 4398 8890
      4398 8960 4425 8960 4425 9032
TIME...MOT...LOC 0524Z 296DEG 35KT 4426 8982

MPC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1251 AM CDT TUE AUG 25 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1225 AM     HAIL             3 NW NEKOOSA            44.34N 89.92W
08/25/2020  M1.25 INCH       WOOD               WI   TRAINED SPOTTER

&&

HYKIN

Special Weather Statement
National Weather Service Green Bay WI
225 AM CDT Tue Aug 25 2020

WIZ005-010>013-018-019-251030-
Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln-
Langlade-
225 AM CDT Tue Aug 25 2020

...LOCALLY DENSE FOG EXPECTED EARLY THIS MORNING...

Clearing skies and abundant low level moisture has led to some
patchy fog development across portions of north-central Wisconsin
early this morning. The fog may become locally dense at times,
reducing visibility to one-quarter of a mile. The fog is expected
to quickly dissipate around sunrise.

If traveling this morning, be prepared for sudden changes in
visibility and be sure to allow extra time to reach your
destination.

Kurimski

Special Weather Statement
National Weather Service Green Bay WI
249 AM CDT Tue Aug 25 2020

WIZ045-048-250830-
Winnebago WI-Waushara WI-
249 AM CDT Tue Aug 25 2020

...SPECIAL WEATHER STATEMENT...

At 248 AM CDT, Doppler radar was tracking a strong thunderstorm near
Lake Poygan, or 9 miles north of Berlin, moving east at 40 mph.

Pea size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Oshkosh, Redgranite, Central Lake Winnebago, Lake Poygan, Northern
Lake Winnebago, Omro, Winneconne, Eureka, Butte Des Morts and Lake
Butte Des Morts.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

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

&&

LAT...LON 4389 8859 4397 8889 4398 8889 4398 8892
      4403 8910 4420 8903 4411 8840 4389 8840
TIME...MOT...LOC 0748Z 286DEG 37KT 4410 8897

Cooley