Alert archive / South Dakota / Mesoscale Discussions in 2019
Mesoscale Discussion 1521
The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2019, 12:26 AM MDT for 4 states. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 19, 2019, 12:26 AM MDT (06:26 UTC)
- Expired
- Jul 19, 2019, 3:00 AM MDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
Counties Carter County, MT, Adams County, ND, Bowman County, ND, Butte County, SD, Corson County, SD, Harding County, SD, Lawrence County, SD, Meade County, SD, Perkins County, SD, Ziebach County, SD, Crook County, WY
The radar
The Rapid City radar (KUDX), 131 km from the middle of the area, began a volume at 06:26 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 nearest sounding before it
Rapid City, SD (KUNR), launched 00:00Z, 6.4 hours before the alert went out and 136 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.
- Mixed-layer CAPE
- 1645 J/kg
- Mixed-layer CIN
- -82 J/kg
- Mixed-layer LCL
- 1566 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 95 m²/s²
- 0-3 km storm-relative helicity
- 304 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 13.3
The text
As transmitted.
568
ACUS11 KWNS 190627
SWOMCD
SPC MCD 190626
SDZ000-NDZ000-MTZ000-WYZ000-190900-
Mesoscale Discussion 1521
NWS Storm Prediction Center Norman OK
0126 AM CDT Fri Jul 19 2019
Areas affected...Portions of far southeastern MT...far northeastern
WY...far southwestern ND...and northwestern SD
Concerning...01Z Outlook upgrade
Valid 190626Z - 190900Z
SUMMARY...Isolated severe risk should continue overnight. Large hail
appears to be the main threat. Overall threat will probably remain
too isolated for a watch.
DISCUSSION...Storms have recently strengthened across far
southeastern MT into far southwestern ND along and just ahead of a
cold front. Ascent overspreading this region associated with a
subtle shortwave trough embedded within enhanced mid/upper-level
westerly flow may also be aiding storm development. This convection
will likely remain elevated above a shallow near-surface stable
layer. But, steep mid-level lapse rates are contributing to
1500-2500+ MUCAPE, which increases with eastward extent across
western SD. Strong mid/upper-level winds will support elevated
supercells early this morning with mainly a large hail threat given
the 50-60 kt of effective bulk shear. This threat for isolated large
hail will probably persist for the next couple of hours into parts
of far southwestern ND and northwestern SD. At least a marginal risk
of severe storms is apparent, but the overall threat will probably
remain too isolated to justify watch issuance.
..Gleason/Grams.. 07/19/2019
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ABR...BIS...UNR...BYZ...
LAT...LON 45130531 45660492 46260364 46370291 46330179 45930090
45010089 44470157 44170262 44180404 44510499 45130531SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 6:08 AM MDT | Mesoscale Discussion | SPC | Brown, Clark, Codington, Day, Edmunds, Faulk and 5 more | 2 hr |
| Jul 19, 10:06 AM MDT | Mesoscale Discussion | SPC | Codington, Deuel, Grant | 114 min |
Nearby
Mesoscale Discussions in South Dakota, 2019Mesoscale Discussions in North Dakota, 2019Mesoscale Discussions in Montana, 2019Every mesoscale discussion in 2019
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.