Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
759 PM CDT Sat Aug 28 2021

.UPDATED for 00Z Aviation Discussion...
Issued at 748 PM CDT Sat Aug 28 2021

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 342 PM CDT Sat Aug 28 2021

Robust late morning convection dropped some impressive hail and
heavy rain across central Minnesota. This has taken some of the
punch out of the atmosphere and some recovery will need to happen
for this area to see another round of strong to severe storms this
evening. Further south, some overnight/early morning convection
across Iowa has robbed our instability across southern Minnesota as
more stable air has been advected northward. This prevented the late
morning Minnesota storms from expanding further southward. Still, a
few spotty pop up showers and thunderstorms have managed to develop
along an outflow boundary stalled out just northwest of the Twin
Cities metro.

Regarding chances for a second round of severe thunderstorms, things
are less certain. Our 18z sounding showed a favorable environment
with MU CAPE of over 1500 J/kg, low and mid level lapse rates of
around 7 C/km, and 0-6km shear of 35 kts. However, there is a cap in
place at the lower levels thanks to the more stable air being
advected northward. Taking a step back and looking at the bigger
picture, the main trough is still back over the western Dakotas with
the surface cold front just out ahead of it in eastern North Dakota.
A secondary surface low associated with the warm front that was the
focus for our morning convection is centered in Nebraska. Within the
last hour, storms have started firing along the triple point to the
west of Sioux Falls. Because of the morning activity, confidence has
decreased somewhat for our second round of severe weather and focus
has shifted to the heavy rain threat. In any case, we will see a
line of showers and thunderstorms to move across the CWA this
evening through the overnight hours associated with the cold front.

Behind the front, we will see a much nicer second half of
the weekend with seasonably cooler temperatures and plenty of
sunshine.

.LONG TERM...(Monday through Saturday)
Issued at 342 PM CDT Sat Aug 28 2021

For the long term, seasonably cooler temperatures will continue with
zonal flow in place for the first half of the week. We'll see
occasional shower chances increase as we head into the first few
days of meteorological fall with the highest chances coming Thursday
into Friday, but have opted to leave NBM PoPs as is until there is
higher confidence in timing.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 748 PM CDT Sat Aug 28 2021

Thunderstorms are expected to develop this evening. IFR conditions,
strong winds, and gusty A cold front will move through the region
later tonight into Sunday morning, and that will bring an end to the
precipitation chances. Look for VFR conditions with northwest winds
on Sunday.

KMSP...
Thunderstorms will continue at times this evening and into the
overnight hours. A few could produce IFR conditions and gusty winds.
The storm should exit the region around or shortly after 06Z.

/OUTLOOK FOR KMSP/
Mon...VFR. Wind variable less than 5 kts.
Tue...VFR. Wind SE 10 kts.
Wed...VFR. Wind SW 5-10 kts

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&

SHORT TERM...Dye
LONG TERM...Dye
AVIATION...JRB

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
338 PM CDT Sat Aug 28 2021

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
292045-
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns-
Benton-Sherburne-Isanti-Chisago-Lac Qui Parle-Swift-Chippewa-
Kandiyohi-Meeker-Wright-Hennepin-Anoka-Ramsey-Washington-
Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota-
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-Polk-Barron-Rusk-
St. Croix-Pierce-Dunn-Pepin-Eau Claire-
338 PM CDT Sat Aug 28 2021

This Hazardous Weather Outlook is for portions of central and
southern Minnesota, and west central Wisconsin.

.DAY ONE...Tonight.

Another round of rain and thunderstorms is expected this
evening and tonight with the best chances south of I-94 in
Minnesota. The primary threats with these storms will be damaging
winds and large hail with a few tornadoes also possible. In
addition, areas of heavy rain may lead to minor flooding.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will likely be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
751 PM CDT SAT AUG 28 2021

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

0620 PM     TSTM WND DMG     COMFREY                 44.11N 94.90W
08/28/2021                   BROWN              MN   TRAINED SPOTTER

            LARGE TREE UPROOTED. PIC SENT VIA TWITTER.

&&

CTG

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
807 PM CDT Sat Aug 28 2021

MNZ070-077-078-290130-
Dakota MN-Rice MN-Goodhue MN-
807 PM CDT Sat Aug 28 2021

...A strong thunderstorm will impact portions of southwestern Dakota,
west central Goodhue and central Rice Counties through 830 PM CDT...

At 807 PM CDT, Doppler radar was tracking a strong thunderstorm near
Dundas, or 6 miles southwest of Northfield, moving northeast at 40
mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This strong thunderstorm will be near...
  Dundas around 815 PM CDT.
  Northfield around 820 PM CDT.
  Stanton around 825 PM CDT.

Other locations in the path of this storm include Cannon Falls.

This includes Interstate 35 between mile markers 57 and 73.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central Minnesota.

&&

LAT...LON 4427 9338 4447 9343 4465 9300 4437 9279
TIME...MOT...LOC 0107Z 242DEG 35KT 4441 9328

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

NDC

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
817 PM CDT Sat Aug 28 2021

MNZ073-074-290145-
Brown MN-Redwood MN-
817 PM CDT Sat Aug 28 2021

...A strong thunderstorm will impact portions of southern Redwood and
west central Brown Counties through 845 PM CDT...

At 816 PM CDT, Doppler radar was tracking a strong thunderstorm near
Lamberton, or 20 miles southwest of Redwood Falls, moving east at 30
mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This strong thunderstorm will be near...
  Wabasso around 830 PM CDT.

This includes the following highways...
 U.S. Highway 14 between mile markers 45 and 82.
 U.S. Highway 71 between mile markers 52 and 69.

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.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in the Twin Cities.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central and southwestern Minnesota.

&&

LAT...LON 4432 9559 4446 9512 4424 9478 4415 9510
      4420 9510 4420 9558
TIME...MOT...LOC 0116Z 247DEG 25KT 4427 9529

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Dye

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
826 PM CDT Sat Aug 28 2021

MNZ070-077-078-WIZ024-290200-
Dakota MN-Rice MN-Goodhue MN-Pierce WI-
826 PM CDT Sat Aug 28 2021

...Strong thunderstorms will impact portions of southeastern Dakota,
northwestern Goodhue, northeastern Rice and western Pierce Counties
through 900 PM CDT...

At 826 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles south of Rosemount to near Northfield.
Movement was northeast at 45 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Strong thunderstorms will be near...
  Hastings and Cannon Falls around 840 PM CDT.
  Prescott around 845 PM CDT.

Other locations in the path of these storms include Welch and Red
Wing.

This includes U.S. Highway 61 between mile markers 95 and 104.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central Minnesota.

&&

LAT...LON 4466 9313 4475 9284 4475 9281 4476 9281
      4483 9259 4439 9261 4430 9320
TIME...MOT...LOC 0126Z 242DEG 39KT 4466 9303 4442 9311

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

NDC

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
857 PM CDT Sat Aug 28 2021

MNZ078-WIZ023-024-290230-
Goodhue MN-Pierce WI-St. Croix WI-
857 PM CDT Sat Aug 28 2021

...Strong thunderstorms will impact portions of northeastern Goodhue,
central Pierce and south central St. Croix Counties through 930 PM
CDT...

At 857 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles south of River Falls to 5 miles north
of Goodhue. Movement was east at 25 mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Strong thunderstorms will be near...
  Red Wing around 910 PM CDT.
  Ellsworth around 915 PM CDT.

Other locations in the path of these storms include Bay City.

This includes U.S. Highway 61 between mile markers 82 and 103.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4439 9274 4463 9276 4463 9273 4471 9273
      4474 9277 4478 9277 4492 9235 4451 9234
TIME...MOT...LOC 0157Z 250DEG 21KT 4476 9264 4448 9264

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

NDC

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
859 PM CDT Sat Aug 28 2021

MNZ073-074-290230-
Brown MN-Redwood MN-
859 PM CDT Sat Aug 28 2021

...A strong thunderstorm will impact portions of south central
Redwood and southwestern Brown Counties through 930 PM CDT...

At 858 PM CDT, Doppler radar was tracking a strong thunderstorm near
Lamberton, or 22 miles north of Windom, moving east at 25 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
  Springfield.

This includes the following highways...
 U.S. Highway 14 between mile markers 54 and 74.
 U.S. Highway 71 between mile markers 52 and 60.

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.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central and southwestern Minnesota.

&&

LAT...LON 4420 9510 4419 9540 4421 9544 4435 9507
      4411 9487 4411 9509
TIME...MOT...LOC 0158Z 250DEG 24KT 4419 9522

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Dye