Severe Thunderstorm Warning 207, NWS Aberdeen, SD

Area Forecast Discussion
National Weather Service Aberdeen SD
158 AM CDT Fri Aug 8 2025

.KEY MESSAGES...

- Two scenarios for today. Warm air aloft keeps us capped. The other
option, if we get convection, is for either an isolated storm
through during the morning hours along the SD/ND state line, or a
stronger storm or two late afternoon/evening (30-45%) mainly in far
northeastern SD/west central MN.

- There is a slight risk (level 2 out of 5) for highway 281 and
points east. Marginal risk (1 of 5) elsewhere. Hail/high winds are
the primary threat. Isolated tornado risk is focused in western
Minnesota.

&&

.DISCUSSION...
Issued at 157 AM CDT Fri Aug 8 2025

A line of storms have set up from Hettinger all the way northeast to
Devils lake proceeding to the east. the south end of this line is
encountering very warm air loft, with 700 temperatures running at
approximately 15 to 16 Celsius. That is between one to two standard
deviations above climatology. This strong cap is situated above a
layer of Stratus. Thus the main concern going forward is the impact
of these stable boundary layer conditions on future convective
initiation. convective allowing models seem to have a very good
grasp of these conditions and are limiting convection across much of
the cwa through the course of the late morning and into the
afternoon hours, with a few indicating cells penetrating into south
dakota before dissipating. there are some hints in these convective
allowing models that some of the better chances for elevated
convection sets up across the far northeast later this morning ahead
of the warmest air aloft. A surface boundary will then provide the
focus for re-developmant as it moves across the area through the
daylight hours and judging by BUFKIT profiles we have a very tenuous
ability to breach the cap with this feature on our northern
periphery. That said steep lapse rates aloft Will enhance the severe
weather potential for any storms that do manage, with NAM/HREF
MLCAPE > 4000j/kg... but if we look at BUFKIT this would probably be
closer to 3000-35000j/kg elevated CAPE since its generated from the
top of the inversion with the passage of the boundary. Shear is
quite good for severe weather as well, at about 40kts with strong
mid-level southwesterlies this evening. Overnight with warm
advection and enhancing low level flow with decoupling, elevated
convection could get going in the far northeast and western
minnesota prior to midnight before moving out of the cwa.

Once the front moves through we'll see cold air advection tonight
with the core of coldest air aloft moving through Sunday. The HRRR
and RUC Currently do not run far enough, However smoke aloft and
near surface situated just west of the area by the end of these runs
will be a concern for the weekend and into next week as the source
region is out of Canada. The northwest flow regime degrades on
Tuesday with a zonal/wobbly pattern for the rest of the extended.
Its about that time of year where this fetch Would generate less
convective activity and as such NBM pops are too low for a mention
of storms until we get into late in the work week.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1218 AM CDT Fri Aug 8 2025

Terminals KABR,KATY,KPIR,KMBG

MVFR CIGS in KABR/KATY will persist, and develop into KMBG
through the early morning hours. CIGS may drop to IFR at some
point in the morning for KABR/KATY terminals as well. Otherwise,
tracking convection up in North Dakota currently could impact the
KMBG terminal but not a high enough probability of occurrence for
including in KABR TAF. Later this afternoon, convective
redevelopment is more probable for KABR/KATY. Will also see a wind
shift from SE/E to NW with the passage of a front through the
afternoon/evening.

&&

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

DISCUSSION...07
AVIATION...07

Hazardous Weather Outlook
National Weather Service Aberdeen SD
906 PM CDT Thu Aug 7 2025

MNZ039-046-SDZ003>011-015>023-034-036-037-090215-
Traverse-Big Stone-Corson-Campbell-McPherson-Brown-Marshall-Roberts-
Walworth-Edmunds-Day-Dewey-Potter-Faulk-Spink-Clark-Codington-Grant-
Hamlin-Deuel-Sully-Hyde-Hand-
906 PM CDT Thu Aug 7 2025 /806 PM MDT Thu Aug 7 2025/

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

.DAY ONE...Tonight.

Storms over North Dakota may form into a bowing line or lines of
storms that move over portions of northern South Dakota overnight.
Confidence is only low to moderate for this to occur, with mainly dry
weather being more likely. There is an Enhanced Risk, level 3 out of
5, for severe storms near the North Dakota, South Dakota line north
Eureka to Britton. Otherwise, there is a Slight Risk, level 2 out of
5, for severe storms. While large hail of around the size of
quarters will be possible, the main concern will be damaging winds in
excess of 60 to 70 mph.

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

There is a Slight Risk, level 2 out of 5, for severe storms mainly
near and east of the James River Friday into Friday evening. If
strong storms develop, all hazards are possible, including the
potential for a couple of tornadoes.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested. 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 X
feed.

SDZ033-035-045-048-051-090215-
Stanley-Hughes-Jones-Lyman-Buffalo-
906 PM CDT Thu Aug 7 2025 /806 PM MDT Thu Aug 7 2025/

This Hazardous Weather Outlook is for central South Dakota.

.DAY ONE...Tonight.

There is a Marginal Risk, level 1 out of 5, of severe weather. If
strong storms are able to develop, they would be capable of producing
damaging winds of around 60 mph or hail the size of quarters.

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

There is a Marginal Risk, level 1 out of 5, of severe weather Friday
morning and afternoon. If strong storms develop, they would be
capable of producing damaging winds of around 60 mph or hail the size
of quarters.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested. 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 X
feed.

06

Special Weather Statement
National Weather Service Aberdeen SD
1218 AM MDT Fri Aug 8 2025

SDZ003-015-080730-
Dewey SD-Corson SD-
1218 AM MDT Fri Aug 8 2025

...STRONG THUNDERSTORMS WILL IMPACT WESTERN CORSON AND NORTHWESTERN
DEWEY COUNTIES THROUGH 130 AM MDT...

At 1217 AM MDT, Doppler radar was tracking the outflow from strong
thunderstorms along a line extending from 9 miles north of Thunder
Hawk to near Chance. Movement was east at 35 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Bullhead, Mcintosh, Isabel, Morristown, Firesteel, Watauga, Black
Horse, Walker, Thunder Hawk, Keldron, Shambo Ranch, Klein Ranch, and
southern Standing Rock Nation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4594 10200 4594 10097 4537 10120 4536 10149
      4538 10149 4539 10147 4547 10147 4547 10200
TIME...MOT...LOC 0617Z 258DEG 32KT 4608 10199 4536 10227

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

10

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>