Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
213 PM CDT Sun Jun 24 2018

.SHORT TERM...(This evening through Tuesday)
Issued at 212 PM CDT Sun Jun 24 2018

Current radar imagery shows some scattered showers/thunderstorms
across the area, with the main activity focused from southwest
into south central Minnesota, and secondary activity northeast of
the Twin Cities metro. The larger scale activity from earlier in
the day dissipated as it moved toward the metro and into an area
of reduced deep layer moisture along the leading edge of the 850
mb theta-e gradient. However, activity was able to develop in the
north/east metro where convergence was enhanced due to northeast
flow that worked its way down from Lake Superior. Expect to see
more widespread convection develop to our west/southwest this
evening/tonight which will try to move across the forecast area
again on Monday, but once again it looks like it will tend to fade
as it moves east into drier air. However, we will eventually see
the shortwave over the eastern Rockies work its way eastward,
which will bring a more widespread area of showers/thunderstorms
across the forecast area Monday night into Tuesday morning as its
associated surface low moves east along the Minnesota/Iowa border.
This could certainly exacerbate ongoing flooding issues and delay
cessation or increase the crests of river levels. The better
juxtaposition of instability and shear still looks to be to our
south, so the main potential of any severe weather still looks to
be in that area, although a few severe storms can't be ruled out.

.LONG TERM...(Tuesday night through Sunday)
Issued at 212 PM CDT Sun Jun 24 2018

Once the Tuesday shortwave trough kicks east it still appears we
will see ridging build across the central CONUS with troughing
setting up over the western CONUS by the end of the week. This
should lead to some active weather in the region from Thursday
night into the weekend with southwest upper flow initially west of
the region slowly pushing east with time. However, the guidance
still shows a fair amount of spread with where/when MCS activity
will develop and move, so the forecast will still have some chance
PoPs for a greater period of time than there will likely be
precipitation in the area. The are also some significant
differences on when the strong upper ridge will be displaced
eastward, which will obviously impact the forecast as we head
through the weekend. The ECMWF and Canadian are more progressive
than the GFS and FV3 solutions. At this point, don't have too much
confidence to favor one over the other, although upper ridges of
this forecast magnitude at this time of year are often more
stubborn than guidance would like them to be.

Any precipitation with the Monday night/Tuesday system should
shift east Tuesday night, with a weak ridge of high pressure
bringing warm and dry weather for Tuesday night and most of
Wednesday (a weak shortwave trough passing by to our north could
bring some shower/thunderstorm activity through late Wednesday).
Warm advection and moisture return will dramatically increase on
Thursday as low pressure sets up in the lee of Rockies. The
guidance currently suggests this will lead to widespread
convection (MCS activity) across the Dakotas on Thursday that will
lift northeast through northern Minnesota Thursday night into
Friday, while we remain hot, humid, and capped. After that the
guidance has much more spread due to differences with how quickly
they bring the western trough east and push the cold frontal
boundary through our area. The ECMWF and Canadian would bring it
through Friday night and early Saturday, while the GFS would delay
it by at least 24 hours (the FV3 from 06Z was somewhat between
these solutions). Our main chance for precipitation currently
looks tied to this frontal passage and forcing from the
association shortwave trough. So, will need to carry PoPs for much
of the time period from late Friday into Sunday to account for the
differences in timing and evolution.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 121 PM CDT Sun Jun 24 2018

Lots of forecast challenges out there today. We've seen a cold front
come down from Lake Superior that stretches from Alexandria, down
I-94 into Minneapolis, and off from there just to the south of
Menomonie and Eau Claire in WI. There has been a decaying cluster
of storms lumbering across southern MN all morning. Thunderstorms
developing in the northeast Twin Cities metro went up along the
interface between the front and cloud shield from decaying storms.
These will stay northeast of MSP, but will likely impact RNH.
Otherwise, location of instability and forcing over the next 24
hours looks to remain relatively station or even retreat westward
some. This means we'll continue to see the greatest threat for
additional storm potential out along the MN/SD border, with RWF
have the greatest threat of seeing additional shra/tsra through
Monday morning. We did follow the LAV and other hi-res models with
allowing MVFR cigs to develop in western MN late tonight through
Monday morning, but confidence is not overly high that this will
occur.

KMSP...Storms northeast of the metro may impact arrival/departure
gates to the northeast, but we are not anticipating any storms to
impact MSP this afternoon with these storms remaining northeast of
MSP. It may not be until Monday evening before MSP finally gets
into better forcing for precip.

/OUTLOOK FOR KMSP/
Tue...MVFR/-SHRA/-TSRA likely. Wind E bcmg NW 5-10 kts.
Wed...Chc morning MVFR. Winds NW 5-10 kts.
Thu...VFR. Winds SE 10G20 kts.

&&

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

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

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
231 PM CDT Sun Jun 24 2018

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
251945-
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-
231 PM CDT Sun Jun 24 2018

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

.DAY ONE...This Afternoon and Tonight

Any thunderstorms that develop through tonight are capable of
producing very heavy rainfall, gusty winds and small hail.
Severe weather is not expected. The greatest risk for seeing heavy
rainfall and flooding will be across southwest into south central
MN.

River flooding will continue along the Minnesota River and
its tributaries.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Thunderstorms with heavy rainfall will occur across the region
Monday and Tuesday. Severe weather potential is low at this time.

River flooding will continue along the Minnesota River and its
tributaries through next week.

The heat and humidity will begin to build late this week. This
will come with an increasing threat for thunderstorms, possibly
severe, and heavy rainfall.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation will not be needed.

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
1122 AM CDT SUN JUN 24 2018

MNZ075-082-083-241715-
Blue Earth-Watonwan-Nicollet-
1122 AM CDT SUN JUN 24 2018

...A STRONG THUNDERSTORM WILL AFFECT WESTERN BLUE EARTH...
NORTHEASTERN WATONWAN AND SOUTHEASTERN NICOLLET COUNTIES...

At 1121 AM CDT, a strong thunderstorm was located near Lake Crystal,
or 15 miles southeast of New Ulm, moving east at 15 mph.

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

Locations impacted include...
North Mankato, Lake Crystal, Madelia, Nicollet, Good Thunder, Vernon
Center, Garden City and Judson.

This includes the following highways...
 U.S. Highway 14 between mile markers 119 and 127.
 U.S. Highway 169 between mile markers 31 and 50.

Torrential rainfall is also occurring with this storm, and may cause
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 4402 9449 4411 9447 4411 9437 4408 9437
      4405 9427 4429 9419 4429 9404 4389 9409
TIME...MOT...LOC 1621Z 277DEG 13KT 4411 9431

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
104 PM CDT SUN JUN 24 2018

MNZ061>063-WIZ014-023-241900-
Anoka-Washington-Ramsey-Polk-St. Croix-
104 PM CDT SUN JUN 24 2018

...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT EAST CENTRAL ANOKA...
NORTHERN WASHINGTON...NORTHEASTERN RAMSEY...WESTERN ST. CROIX AND
SOUTH CENTRAL POLK COUNTIES...

At 104 PM CDT, strong thunderstorms were clustered over Stillwater,
or 17 miles northwest of River Falls, moving north at 10 mph.

Winds in excess of 25 mph and pea size hail are possible with these
storm.

Locations impacted include...
Oakdale, White Bear Lake, Lino Lakes, Forest Lake, Stillwater, Hugo,
Hudson, Vadnais Heights, New Richmond, Lake Elmo, Mahtomedi and
Chisago City.

This includes the following highways...
 Interstate 35 between mile markers 130 and 132.
 Interstate 94 in Wisconsin between mile markers 1 and 8.
 U.S. Highway 8 in Minnesota between mile markers 0 and 1.

Torrential rainfall is also occurring with these storms, and may
cause localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 4531 9302 4529 9302 4530 9293 4520 9235
      4491 9265 4506 9306 4533 9313
TIME...MOT...LOC 1804Z 187DEG 11KT 4509 9278

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
120 PM CDT SUN JUN 24 2018

MNZ074-082-091-241915-
Brown-Watonwan-Martin-
120 PM CDT SUN JUN 24 2018

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN MARTIN...SOUTH CENTRAL
BROWN AND WATONWAN COUNTIES...

At 120 PM CDT, a strong thunderstorm was located near Odin, or 13
miles east of Windom, moving northeast at 15 mph.

Winds in excess of 25 mph and pea size hail are possible with this
storm.

Locations impacted include...
Fairmont, St. James, Sherburn, Truman, Trimont, Welcome, Butterfield,
South Branch, Northrop, Ormsby, Darfur and Odin.

This includes Interstate 90 between mile markers 82 and 106.

Torrential rainfall is also occurring with this storm, and may cause
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 4411 9486 4424 9469 4366 9435 4363 9485
TIME...MOT...LOC 1820Z 242DEG 15KT 4386 9484

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
130 PM CDT SUN JUN 24 2018

MNZ083-084-091-092-241915-
Waseca-Blue Earth-Martin-Faribault-
130 PM CDT SUN JUN 24 2018

...A STRONG THUNDERSTORM WILL AFFECT FARIBAULT...EASTERN MARTIN...
SOUTHEASTERN BLUE EARTH AND SOUTHERN WASECA COUNTIES...

At 130 PM CDT, a strong thunderstorm was located near Minnesota Lake,
or 20 miles south of Mankato, moving east at 10 mph.

Winds in excess of 25 mph and pea size hail are possible with this
storm.

Locations impacted include...
Blue Earth, Mapleton, Winnebago, Minnesota Lake, Pemberton, Waldorf,
Easton, Frost, Delavan and Otisco.

This includes the following highways...
 Interstate 90 between mile markers 118 and 132.
 U.S. Highway 169 between mile markers 10 and 27.

Torrential rainfall is also occurring with this storm, and may cause
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 4380 9434 4403 9377 4400 9348 4355 9397
TIME...MOT...LOC 1830Z 286DEG 10KT 4389 9384

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
325 PM CDT SUN JUN 24 2018

MNZ092-242115-
Faribault-
325 PM CDT SUN JUN 24 2018

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL FARIBAULT COUNTY...

At 325 PM CDT, a strong thunderstorm was located over Blue Earth, or
18 miles east of Fairmont, moving east at 10 mph.

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

Locations impacted include...
Blue Earth, Frost, Brush Creek and Huntley.

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

LAT...LON 4355 9423 4375 9417 4372 9380 4352 9389
TIME...MOT...LOC 2025Z 282DEG 10KT 4365 9411

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Twin Cities/Chanhassen MN
427 PM CDT SUN JUN 24 2018

MNZ092-250030-
Faribault-
427 PM CDT SUN JUN 24 2018

...VERY HEAVY RAIN AND LOCALIZED MINOR FLOODING EXPECTED...

VERY HEAVY RAIN WITH THE POTENTIAL FOR LOCALIZED FLOODING WILL AFFECT
THE FOLLOWING COUNTIES...

Faribault...

At 423 PM CDT...Radar precipitation estimates show 3 to 6 inches of
rain has fallen this afternoon in and near the city of Blue Earth.
This heavy rainfall will lead ponding of water in low spots, with
high water expecting to slowly recede over the next couple of hours
as the rainfall moves out of central Faribault county.

LOCATIONS IMPACTED INCLUDE...
Blue Earth and Frost.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...AS WELL AS FARM AND COUNTRY ROADS. DO NOT
ATTEMPT TO TRAVEL ACROSS FLOODED ROADS. FIND ALTERNATE ROUTES.

LAT...LON 4358 9417 4375 9414 4371 9384 4350 9388
      4350 9391
TIME...MOT...LOC 2123Z 318DEG 0KT 4365 9410