Severe Thunderstorm Warning 8, NWS Aberdeen, SD

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
631 PM CDT Thu Jun 4 2020

.UPDATE...
Issued at 629 PM CDT Thu Jun 4 2020

Other than some hourly tweaks to pops, forecast remains on track
with a few strong to severe storms around the area.

&&

.SHORT TERM...(This Evening through Friday Night)
Issued at 348 PM CDT Thu Jun 4 2020

Forecast challenges include areal coverage/timing of convection and
areal coverage of severe storms.

Currently, temperatures are warming through the 70s into the low 80s
across the region on a developing southeasterly breeze. Skies are
partly to mostly sunny this afternoon, allowing for adequate daytime
insolation, aiding the current increasing instability west and south
in the region. Objective analysis off the SPC Meso page reveals
there is between 40 and 55 knots of deep layer shear available for
storms to work with, and likely to persist into the evening. The
surface trof/cool front the pushed through the region late last
night/early this morning is splayed out along the NE/SD border, with
plenty of boundary layer (0.5km to 850hpa layer) moisture found
pooling along and behind it this afternoon, per surface/MSAS
analysis. A secondary surface trof/cool front feature is noted again
this afternoon across far western ND tailing back into northwestern
WY, the likely forcing mechanism behind the current batch of showers
and thunderstorms that began developing between 1PM and 2PM CDT back
over southeastern MT and southwestern ND. The mid-level shortwave
impulse of interest is moving into the region, riding through 80 to
90+kt upper level jet stream winds. Severe Thunderstorm Watch 252
has been issued and is in effect until 11 PM CDT for several
counties across the western/southwestern forecast zones.

Expecting widely scattered to scattered coverage of discrete
splitting supercells west river and into the Missouri River valley
through late this evening per model hodographs, and given the
synoptic scale setup and the available pool of +12C to +14C 850hpa
dewpoint air, right-moving supercells will move into very moisture
rich boundary layer air to work with. A lack of 0-1km shear suggests
tornadic storms are less likely this afternoon/evening, with large
hail and damaging winds more probable. But, given the right
conditions, an isolated tornado is not completely out of the
question. That's what storm coverage/intensity looks like west of a
line from Mobridge to Gann Valley through late this evening. East of
that line, deep layer shear remains strong, but considerably less
favorable low level moisture and mid-level lapse rates prevail from
now through late tonight. There should be scattered/numerous
coverage of showers and thunderstorms working through northeast SD
through late this evening, but probably not of the strong to severe
variety.

Heading into Friday and Friday night, the forecast dries out as the
pattern aloft begins to take on a more amplified look and feel while
western CONUS longwave troffiness develops. At the surface,
cooler/drier airmass high pressure will be in control over the
region. Temperatures throughout the period should be running right
about normal to perhaps a degree or two above normal.

.LONG TERM...(Saturday through Thursday)
Issued at 348 PM CDT Thu Jun 4 2020

First issue in the extended is the thunderstorm chances Saturday
into Saturday night. Ingredients look good for severe storms, but
may have to deal with capping issues as 700mb temps approach +12C to
+13C over central SD. Interesting to note some of the deterministic
models are fairly scant for precipitation coverage. That said, will
maintain inherited POPs which really ramp things up by Saturday
night. Approach of the mid level shortwave should help erode
whatever cap is in place by later in the day and into the overnight
hours. Very strong low level jet will be in place as well Saturday
night. Will continue to have chances for showers and thunderstorms
through Monday as we await the passage of the cold front.

Temperatures will become rather toasty Sunday and Monday as 850mb
temps rise into the +20s C by Sunday afternoon. Looking at
widespread 90s on Sunday, with humid conditions setting in as well.
Cooler temperatures will arrive on Tuesday with the passage of
Monday's cold front.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 629 PM CDT Thu Jun 4 2020

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected except near thunderstorms this evening
where temporary IFR vsby is possible.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

UPDATE...Wise
SHORT TERM...Dorn
LONG TERM...TMT
AVIATION...Wise

Hazardous Weather Outlook
National Weather Service Aberdeen SD
337 PM CDT Thu Jun 4 2020

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-052045-
Traverse-Big Stone-Corson-Campbell-McPherson-Brown-Marshall-Roberts-
Walworth-Edmunds-Day-Dewey-Potter-Faulk-Spink-Clark-Codington-Grant-
Hamlin-Deuel-Stanley-Sully-Hughes-Hyde-Hand-Jones-Lyman-Buffalo-
337 PM CDT Thu Jun 4 2020 /237 PM MDT Thu Jun 4 2020/

This Hazardous Weather Outlook is for west central Minnesota,
central South Dakota, north central South Dakota and northeast
South Dakota.

.DAY ONE...This afternoon and tonight.

Thunderstorms this afternoon into this evening could bring strong
winds, large hail, and an isolated tornado threat. Storms should
weaken and move southeast late in the evening into the overnight.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

A strong system will bring gusty winds, strong to severe storms, and
heavy precipitation to the region this weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Weather spotters are
encouraged to submit reports to the National Weather Service in
Aberdeen. The public can submit reports on our web page, Facebook
page, or our Twitter feed.

Dorn

Special Weather Statement
National Weather Service Aberdeen SD
530 PM CDT Thu Jun 4 2020

SDZ003-004-009-015-042315-
Dewey SD-Walworth SD-Campbell SD-Corson SD-
530 PM CDT Thu Jun 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN CORSON...SOUTHERN
CAMPBELL...NORTHEASTERN DEWEY AND WALWORTH COUNTIES UNTIL 615 PM
CDT/515 PM MDT/...

At 530 PM CDT/430 PM MDT/, Doppler radar was tracking strong
thunderstorms along a line extending from near Mound City to near
Indian Creek Rec Area to near Promise. Movement was east at 45 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Mobridge, Selby, Java, Glenham, Mound City, Akaska, New Everets
Resort, Indian Creek Rec Area, Blackfoot, Promise, Indian Memorial
Rec Area, Swan Creek Rec Area, Revheim Bay Rec Area and Lake
Hiddenwood Rec Area.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT/1000
PM MDT/ for north central South Dakota.

LAT...LON 4559 9972 4559 9971 4551 9970 4546 9974
      4526 10023 4533 10082 4549 10061 4554 10051
      4569 10042 4576 9972
TIME...MOT...LOC 2230Z 274DEG 38KT 4576 10017 4552 10034 4536 10068

KF

Special Weather Statement
National Weather Service Aberdeen SD
552 PM CDT Thu Jun 4 2020

SDZ005-006-010-042330-
Brown SD-McPherson SD-Edmunds SD-
552 PM CDT Thu Jun 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN EDMUNDS...WEST
CENTRAL BROWN AND SOUTHEASTERN MCPHERSON COUNTIES UNTIL 630 PM CDT...

At 552 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles west of Plainview Colony, or 11 miles northwest of Ipswich,
moving east at 40 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations impacted include...
Ipswich, Wetonka, Plainview Colony, Long Lake Colony, Deerfield
Colony, Cravens Corner, Mina, Grassland Colony and Mina Lake Rec
Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4551 9945 4570 9930 4567 9865 4536 9877
TIME...MOT...LOC 2252Z 279DEG 34KT 4556 9920

Wise

Special Weather Statement
National Weather Service Aberdeen SD
619 PM CDT Thu Jun 4 2020

SDZ009-010-016-017-050000-
Walworth SD-Potter SD-Edmunds SD-Faulk SD-
619 PM CDT Thu Jun 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN EDMUNDS...
NORTHWESTERN FAULK...EASTERN POTTER AND SOUTHEASTERN WALWORTH
COUNTIES UNTIL 700 PM CDT...

At 618 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 8 miles south of Bowdle to near Hoven to 6
miles northwest of Gettysburg. Movement was southeast at 35 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Hoven, Lebanon, Seneca, Tolstoy, Onaka and Brentwood Colony.

LAT...LON 4521 9924 4497 9950 4490 9974 4516 10013
      4522 9994 4536 9974
TIME...MOT...LOC 2318Z 309DEG 29KT 4533 9966 4518 9986 4509 10002

KF

Special Weather Statement
National Weather Service Aberdeen SD
627 PM CDT Thu Jun 4 2020

SDZ006-010-050015-
Brown SD-Edmunds SD-
627 PM CDT Thu Jun 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN EDMUNDS AND BROWN
COUNTIES UNTIL 715 PM CDT...

At 627 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Barnard to Richmond Lake Rec Area to near
Mina Lake Rec Area. Movement was east at 45 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Aberdeen, Groton, Bath, Warner, Columbia, Westport, Claremont,
Putney, Stratford, Barnard, Mina, Houghton, Mina Lake Rec Area, Sand
Lake Wildlife Refuge and Richmond Lake Rec Area.

LAT...LON 4552 9798 4530 9833 4539 9892 4557 9876
      4559 9875 4559 9873 4564 9873 4582 9865
      4582 9798
TIME...MOT...LOC 2327Z 269DEG 39KT 4577 9844 4556 9860 4549 9882

KF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ABERDEEN SD
646 PM CDT THU JUN 4 2020

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

0644 PM     TSTM WND GST     2 W RICHMOND LAKE REC A 45.55N 98.64W
06/04/2020  M50 MPH          BROWN              SD   NWS EMPLOYEE

            0 MILE VISIBILITY IN HEAVY RAIN.

&&

KF

Special Weather Statement
National Weather Service Aberdeen SD
551 PM MDT Thu Jun 4 2020

SDZ033-050015-
Stanley SD-
551 PM MDT Thu Jun 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL STANLEY COUNTY UNTIL
615 PM MDT...

At 551 PM MDT, Doppler radar was tracking a strong thunderstorm near
Sansarc, or 33 miles south of Eagle Butte, moving southeast at 35
mph.

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

Locations impacted include...
Sansarc, Brown Church and Hayes.

A Severe Thunderstorm Watch remains in effect until 1000 PM MDT for
central South Dakota.

LAT...LON 4464 10116 4447 10069 4427 10102 4441 10116
TIME...MOT...LOC 2351Z 307DEG 32KT 4453 10114

KF