Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
223 AM CDT Mon Aug 31 2020

.SHORT TERM...(Today through Tuesday)
Issued at 223 AM CDT Mon Aug 31 2020

Satellite and radar imagery show area of showers with some
embedded thunder moving west to east across the area. This
activity is along and ahead of a surface cold front extending from
north central Minnesota southwest into eastern Nebraska. The main
upper trough associated with it can be seen in water vapor imagery
over the central Dakotas. There is a narrow axis of instability,
with MUCAPE values up to around 1500 J/Kg just along/ahead of the
front, currently nosing into southwest and west central Minnesota.
This is maximized near the 850 mb theta-e ridge axis over that
same area, with theta-e values dropping quickly over eastern South
Dakota. Things are moving more slowly than guidance indicated
yesterday, likely due to the upper trough digging a big more than
progged. However, look for things to continue to push east through
the day today, existing the eastern portion of the forecast by
around midday. We should see clearing somewhat quickly behind the
precipitation, especially once we get into daylight hours and
mixing can help with some of the lingering low clouds currently
seen behind the front. Cooler and drier air will then build across
the area into Tuesday as high pressure slides east through the
region.

.LONG TERM...(Tuesday night through Sunday)
Issued at 223 AM CDT Mon Aug 31 2020

The longer term looks fairly quiet in terms of sensible weather,
with a few moisture starved systems moving through the region and
likely not producing much if any precipiation. Northwest upper
flow will predominate through the period, with the main upper
trough over eastern North America significantly amplifying by the
end of the period, signaling the arrival of much cooler
temperatures. However, before that happens we will have a couple
of decent warmups ahead of Alberta Clipper-like systems. Model
guidance is in remarkably good agreement on the overall evolution
of the large scale pattern through the period, making it difficult
to make any significant changes to the blended consensus forecast.
The main chances for any precipitation look to be Wednesday night
into early Thursday as a surface low moves along the US/Canadian
border and drags a frontal boundary through the area. Moisture
return ahead of that system is quite limited, so the best chance
of any precipitation will be over the northern portion of the area
where deep layer saturation is more likely to occur. A better
chance for precipitation will come during the latter half of the
weekend, although there remains disagreement on the timing and
strength of the shortwave trough progged to move through the
region. Overall, will have minimal PoPs through the period, with a
mainly just chance PoPs over the weekend. Mild weather is expected
the much of the week, with spike into the 80s on Wednesday and
Saturday ahead of the two systems of interest.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1151 PM CDT Sun Aug 30 2020

Few changes made to going TAFs. Instability not really following
showers into the area, so expect a continued downward trend in
amount of TSRA across the MPX area through the night. Starting to
see MVFR cigs expand along the cold front, so maintained brief
window of MVFR cigs at all terminals. Best punch of winds behind
the front looks to remain southwest of the MPX terminals, so did
back off on winds some immediately behind the front. No concerns
for much of Monday as skies clear out from west to east.

KMSP...Looking increasingly likely we'll see some thunder with
initial push of activity into the field, but after that, it looks
to be mainly shra. Time window for lowest cigs looks to be between
11z and 13z now, with heights under 018 still a possibility.

/OUTLOOK FOR KMSP/
TUE...VFR. Wind S 5-10 kts.
WED...VFR. Wind WSW 5-10 kts.
THU...VFR. Wind NW 15-20G30kts.

&&

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

SHORT TERM...
LONG TERM...
AVIATION...MPG

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
310 PM CDT Sun Aug 30 2020

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
312015-
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-
310 PM CDT Sun Aug 30 2020

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

.DAY ONE...Tonight.

A few severe storms are possible in far western Minnesota this
evening. The primary threat would be damaging wind gusts and large
hail. Non-severe thunderstorms are possible across the remainder
of the area tonight.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation may be needed across western Minnesota
this evening.

Borghoff

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
917 PM CDT Sun Aug 30 2020

MNZ054-064-310300-
Yellow Medicine-Lac Qui Parle-
917 PM CDT Sun Aug 30 2020

...A STRONG THUNDERSTORM WILL AFFECT LAC QUI PARLE COUNTY...

At 917 PM CDT, a strong thunderstorm was located 6 miles northeast of
Moritz, or 13 miles northeast of Clear Lake, moving east at 60 mph.

Winds in excess of 40 mph and pea size hail are possible with this
storm.

Locations impacted include...
Madison, Dawson, Marietta, Cerro Gordo, Providence, and Florida
Creek Wildlife Management Area.

LAT...LON 4505 9645 4513 9602 4502 9587 4500 9583
      4496 9582 4493 9573 4491 9572 4490 9567
      4478 9645
TIME...MOT...LOC 0217Z 255DEG 50KT 4488 9646

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
216 AM CDT Mon Aug 31 2020

MNZ073>075-310745-
Brown-Nicollet-Redwood-
216 AM CDT Mon Aug 31 2020

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN REDWOOD...CENTRAL
BROWN AND NORTHWESTERN NICOLLET COUNTIES...

At 215 AM CDT, a strong thunderstorm was located near Springfield, or
20 miles southeast of Redwood Falls, moving east at 40 mph.

Winds in excess of 30 mph and dime size hail are possible with this
storm.

Locations impacted include...
New Ulm, Sleepy Eye, Evan, Cobden, Essig, St George and New Ulm
Airport.

LAT...LON 4423 9495 4433 9499 4445 9454 4429 9448
TIME...MOT...LOC 0715Z 258DEG 35KT 4428 9491

BPH

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
249 AM CDT Mon Aug 31 2020

MNZ067-075-310815-
Sibley-Nicollet-
249 AM CDT Mon Aug 31 2020

...A STRONG THUNDERSTORM WILL AFFECT SOUTH CENTRAL SIBLEY AND NORTH
CENTRAL NICOLLET COUNTIES...

At 248 AM CDT, a strong thunderstorm was located near New Ulm, moving
east at 35 mph.

Winds in excess of 30 mph and dime size hail are possible with this
storm.

Locations impacted include...
Lafayette, New Sweden and Klossner.

LAT...LON 4435 9449 4437 9456 4440 9458 4451 9419
      4436 9415 4433 9446
TIME...MOT...LOC 0748Z 256DEG 31KT 4437 9452

BPH