Alert archive / Minnesota / Mesoscale Discussions in 2020

Mesoscale Discussion 1256

July 17, 202035 counties in Minnesota; 7 counties in North Dakota; 20 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 17, 2020, 10:25 PM CDT for 35 counties in Minnesota; 7 counties in North Dakota; 20 counties in South Dakota. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jul 17, 2020, 10:25 PM CDT (03:25 UTC)
Expired
Jul 18, 2020, 12:30 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 380
All 62 counties

Aitkin County, MN, Benton County, MN, Big Stone County, MN, Carlton County, MN, Cass County, MN, Chippewa County, MN, Crow Wing County, MN, Douglas County, MN, Grant County, MN, Isanti County, MN, Itasca County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Lincoln County, MN, Lyon County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Otter Tail County, MN, Pine County, MN, Pope County, MN, Renville County, MN, Saint Louis County, MN, Sherburne County, MN, Stearns County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Traverse County, MN, Wadena County, MN, Wilkin County, MN, Wright County, MN, Yellow Medicine County, MN, Dickey County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Beadle County, SD, Brookings County, SD, Brown County, SD, Campbell County, SD, Clark County, SD, Codington County, SD, Day County, SD, Deuel County, SD, Edmunds County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Kingsbury County, SD, Marshall County, SD, McPherson County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Walworth County, SD

The radar

The Fargo/Grand Forks radar (KMVX), 195 km from the middle of the area, began a volume at 03:25 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.4 hours before the alert went out and 219 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-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2020-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1995 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2020-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1995 J/kg
Mixed-layer CIN
-87 J/kg
Mixed-layer LCL
1267 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
218 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.8

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 17, 7:57 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Becker, Beltrami, Benton, Big Stone and 31 more2 hr
Jul 17, 9:03 PM CDTMesoscale DiscussionSPCCarlton, Carver, Chisago, Dakota, Goodhue, Hennepin and 6 more117 min
Jul 17, 10:25 PM CDTSevere Thunderstorm WatchSPCAnoka, Brown, Carver, Chippewa, Chisago, Dakota and 14 more8 hr
Jul 17, 11:36 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Big Stone, Carlton, Carver and 35 more114 min
Jul 18, 1:31 AM CDTMesoscale DiscussionSPCAnoka, Brown, Carver, Chisago, Cottonwood, Dakota and 17 more89 min
Jul 18, 4:02 AM CDTMesoscale DiscussionSPCWabasha88 min
Jul 18, 3:12 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Brown, Carlton, Carver and 33 more93 min
Jul 18, 3:53 PM CDTSevere Thunderstorm WatchSPCAitkin, Anoka, Benton, Carlton, Carver, Cass and 25 more8 hr
Jul 18, 6:15 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Carver, Cass and 25 more60 min
Jul 18, 1:16 PM CDTMesoscale DiscussionSPCBenson, Billings, Bottineau, Burke, Burleigh, Divide and 19 more119 min

Nearby

Mesoscale Discussions in Minnesota, 2020Mesoscale Discussions in South Dakota, 2020Mesoscale Discussions in North Dakota, 2020Every mesoscale discussion in 2020

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.