Tornado and Hail in Minnesota, May 18, 2022

Area Forecast Discussion
National Weather Service Duluth MN
1233 PM CDT Wed May 18 2022

.DISCUSSION...(Today through Tuesday)
Issued at 432 AM CDT Wed May 18 2022

Several chances for thunderstorms, some severe, today and tomorrow
before drier and cooler conditions settle in for the weekend.

A little 300mb jet streak and associated 500mb shortwave/vorticity
max will push out from the Canadian Prairies today, bringing an area
of low pressure and subsequent cold front to our region. MUCAPE of
500-1500 J/kg, 30-50knots of bulk shear, and a building 850mb LLJ
should work together for an isolated severe threat across much of
the Northland. With a mean wind seemingly very perpendicular to the
cold front, storms may try to remain discrete, but with long
hodographs some cell merging and a messy attempt at a linear
structure could materialize. Some surface based storms are possible
between 21-03Z from the Iron Range through the Twin Ports and to the
Chequamegon-Nicolet National Forest with a minimal tornado threat.
Low level wind profiles don't appear super indicative of a
substantial tornado threat and we are largely expecting primary
hazards to be hail and wind.

Some scattered showers may be possible over northern Minnesota
Thursday morning and early afternoon before our second chance for
thunderstorms builds in over the late afternoon and into the
evening. As a stronger 300mb jet exit region moves over the Northern
Plains and Great Lakes a warm front is progged to lift over central
Minnesota and northern Wisconsin. Models vary somewhat on just how
north this front makes it, and that will be a major determiner of
the severe weather threat. The warm front will be the delineation
for any surface based storms and a subsequent tornado threat, which
may only exist right along our southern CWA border, otherwise severe
wind and hail will be possible. Additionally, models indicate that
mean winds will be very parallel to the warm frontal boundary,
creating a potential flash flooding threat, especially with PWATS
over 1" in NW WI. However, training storms will likely be needed to
realize any flash flooding, as storms will be trucking along with
mean winds near 50knots.

While the severe threat should stay mostly south of Highway 2,
rainfall is still expected over northern MN Thursday afternoon and
evening under the portion of the system with better synoptic
forcing. Upwards of 1" of rain is possible along the International
Border Thursday night into Friday morning, after up to 0.5" may fall
this afternoon and evening. This will likely continue to exacerbate
already historical flooding in the Rainy River Basin, where lakes
and rivers have broken record levels and surpassed 2014 flood
heights. An additional 0.5-1" along the North Shore over the next
two days will also keep rivers running fast. Across the area, expect
high water to likely stay high at least through the weekend as
already swollen waterways are reinforced by widespread rainfall.
Locally higher amounts under thunderstorms could lead to additional
flooding concerns not already addressed with Flood Warnings.

Our weather should quiet down into the weekend, as some cooler air
moves in. Especially Saturday and Sunday morning, some chilly
temperatures may require Frost or Freeze headlines for a portion to
all of the CWA.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1224 PM CDT Wed May 18 2022

VFR but degrading quickly this afternoon as a cluster/line of
thunderstorms crosses. There will likely be IFR conditions, but
for now just covered the TS threat with VCTS in the TAF.
Ammendments likely when the line begins to develop. After the
storms, expect a stratus deck to develop. More storms expected
tomorrow. Westerly winds are expected to decrease overnight.

&&

.MARINE...
Issued at 432 AM CDT Wed May 18 2022

Fairly calm conditions are expected over Lake Superior today and
tomorrow. However, thunderstorms are possible over all of Western
Lake Superior in the afternoons and evenings, and gusty, erratic
winds/waves and cloud-to-water lightning will be possible. Thursday
night into Friday, northeast winds will build over Lake Superior,
and may force waves high enough to warrant a small craft advisory
for portions of the nearshore waters. Westerly winds may become
gusty Friday afternoon, but are largely expected to remain below
20knots, thanks to our springtime stable layer.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  60  45  57  43 /  70  40  40  80
INL  62  41  57  41 /  80  30  60  80
BRD  72  47  64  47 /  70  20  40  80
HYR  64  46  66  49 /  70  60  50  90
ASX  63  45  60  45 /  70  70  40  90

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&

DISCUSSION...Levens
AVIATION...Wolfe
MARINE...Levens

Hazardous Weather Outlook
National Weather Service Duluth MN
406 AM CDT Wed May 18 2022

MNZ010>012-018>021-025-026-033>038-WIZ001>004-006>009-191030-
Koochiching-North St. Louis-Northern Cook/Northern Lake-
North Itasca-Central St. Louis-Southern Lake/North Shore-
Southern Cook/North Shore-North Cass-South Itasca-South Cass-
Crow Wing-Northern Aitkin-South Aitkin-Carlton/South St. Louis-
Pine-Douglas-Bayfield-Ashland-Iron-Burnett-Washburn-Sawyer-Price-
406 AM CDT Wed May 18 2022

This Hazardous Weather Outlook is for portions of northeast
Minnesota and northwest Wisconsin.

.DAY ONE...Today and Tonight

Thunderstorms are possible today into this evening. A few severe
storms are possible this afternoon into this evening, first
developing over northern Minnesota then into northwest Wisconsin
later afternoon into this evening. Large hail and damaging winds
are the main threats with the storms.

High water levels will continue in the Rainy River Basin over far
northern Minnesota, as well as around the Island Lake Reservoir
and areas downstream on the Cloquet River, especially around Side
Lake and Hunter Lake. Minor flooding will continue along the
Mississippi River between Aitkin and Fort Ripley in Crow Wing
County and near Scanlon along the St. Louis River where Flood
Warnings are in effect. A Flood Warning remains in effect for the
Island Lake Reservoir and areas downstream on the Cloquet River.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Another round of strong to severe thunderstorms is possible
Thursday afternoon and evening from the Brainerd Lakes area east
through Pine City and Hinckley into much of northern Wisconsin.
Large hail, damaging wind, and heavy rain are the main threats.

Water levels will remain high across many of the Northland's
rivers, creeks, and streams, especially in the Rainy River Basin,
Island Lake Reservoir, Cloquet River, and the Mississippi Basin.

.SPOTTER INFORMATION STATEMENT...

Skywarn spotters may be needed.

LSZ121-140>148-150-191030-
Bayfield to Oak Point WI-Grand Portage to Grand Marais MN-
Grand Marais to Taconite Harbor MN-
Taconite Harbor to Silver Bay Harbor MN-
Silver Bay Harbor to Two Harbors MN-Two Harbors to Duluth MN-
Duluth MN to Port Wing WI-Port Wing to Sand Island WI-
Sand Island to Bayfield WI-Oak Point to Saxon Harbor WI-
Outer Apostle Islands Beyond 5 NM from Mainland-
406 AM CDT Wed May 18 2022

This Hazardous Weather Outlook is for portions of Lake Superior
and the Nearshore waters of western Lake Superior.

.DAY ONE...Today and Tonight

Strong to severe thunderstorms are possible this afternoon and
evening. Potential hazards include strong wind gusts, large hail,
and frequent cloud to water lightning.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Another round of strong thunderstorms will be possible Thursday
afternoon and evening, mainly along the South Shore and around the
Twin Ports.

Melde

More information may be obtained at the following web address:
http://www.weather.gov/duluth (all lower case)

Special Weather Statement
National Weather Service Duluth MN
148 PM CDT Wed May 18 2022

MNZ018-181915-
North Itasca MN-
148 PM CDT Wed May 18 2022

...A strong thunderstorm will impact portions of northeastern Itasca
County through 215 PM CDT...

At 147 PM CDT, Doppler radar was tracking a strong thunderstorm near
Marcell, or 29 miles north of Grand Rapids, moving east at 25 mph.

HAZARD...Winds gusts up to 30 mph and half inch hail.

SOURCE...Radar indicated.

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

This storm will remain over mainly rural areas of northeastern Itasca
County, including the following locations... North Star Lake,
Talmoon, Gunn Lake, Balsam Lake, Scenic State Park, Spider Lake and
Coon Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors, including anyone on or in the water, should seek
shelter inside a sturdy building or hard topped vehicle.

&&

LAT...LON 4757 9383 4771 9375 4772 9326 4746 9333
      4746 9337
TIME...MOT...LOC 1847Z 280DEG 23KT 4764 9371

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...30 MPH

Britt/PA