Alert archive / North Dakota / Mesoscale Discussions in 2025

Mesoscale Discussion 1821

July 28, 202514 counties in North Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 28, 2025, 6:21 AM MDT for 14 counties in North Dakota. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued: Jul 28, 2025, 6:21 AM MDT (12:21 UTC)
Expired: Jul 28, 2025, 8:15 AM MDT
In force: 114 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch possible
Chance of a watch: 60%

Counties Adams County, ND, Billings County, ND, Burleigh County, ND, Dunn County, ND, Emmons County, ND, Grant County, ND, Hettinger County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Oliver County, ND, Sioux County, ND, Slope County, ND, Stark County, ND

The radar

The Bismarck radar (KBIS), 100 km from the middle of the area, began a volume at 12:23 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 550Jul 28, 7:25 AM MDT

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 0.4 hours before the alert went out and 104 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 574 J/kg
Mixed-layer CIN: -258 J/kg
Mixed-layer LCL: 1128 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 21 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

680 
ACUS11 KWNS 281221
SWOMCD
SPC MCD 281221 
NDZ000-SDZ000-281415-

Mesoscale Discussion 1821
NWS Storm Prediction Center Norman OK
0721 AM CDT Mon Jul 28 2025

Areas affected...parts of western/central ND

Concerning...Severe potential...Watch possible 

Valid 281221Z - 281415Z

Probability of Watch Issuance...60 percent

SUMMARY...A persistent supercell or two may yield a confined swath
of large hail and strong gusts into late morning. Monitoring for
possible Severe Thunderstorm Watch issuance.

DISCUSSION...A couple elevated supercells are ongoing across
southwest/west-central ND, along and just north of I-94. Despite a
lack of reported severe thus far, strong westerly speed shear above
3 km (now sampled by the BIS VWP and 12Z observed sounding) has
sustained persistent organizational structures as these cells spread
across the MT/ND border. This elevated activity is likely to persist
into midday along the buoyancy gradient across western ND. Large
hail and strong gusts should be the primary hazards. Severe wind may
increase if flanking convection can form along the outflow into a
destabilizing airmass over SD. But ongoing low clouds/fog in the
swath of richest low-level moisture casts uncertainty on whether
that scenario may occur soon or later today.

..Grams/Hart.. 07/28/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...ABR...BIS...UNR...

LAT...LON   47340332 47640223 47670131 47700051 47189994 46150002
            45820094 45830219 46140321 46360389 46800394 47340332 

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 28, 4:02 AM MDT	Mesoscale Discussion	SPC	Adams, Billings, Bowman, Dunn, Golden Valley, Grant and 7 more	118 min
Jul 28, 7:31 AM MDT	Severe Thunderstorm Watch	SPC	Adams, Bowman, Burleigh, Dunn, Emmons, Grant and 10 more	6 hr
Jul 28, 9:42 AM MDT	Mesoscale Discussion	SPC	Adams, Bowman, Dickey, Emmons, Grant, Hettinger and 5 more	2 hr

Nearby

Mesoscale Discussions in North Dakota, 2025 Every mesoscale discussion in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.