Alert archive / Minnesota / Mesoscale Discussions in 2021

Mesoscale Discussion 1376

July 28, 20215 counties in Minnesota

The Storm Prediction Center issued this mesoscale discussion at Jul 28, 2021, 3:32 PM CDT for 5 counties in Minnesota. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued
Jul 28, 2021, 3:32 PM CDT (20:32 UTC)
Expired
Jul 28, 2021, 5:30 PM CDT
In force
118 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
40%

Counties Beltrami County, MN, Clearwater County, MN, Lake of the Woods County, MN, Mahnomen County, MN, Red Lake County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 182 km from the middle of the area, began a volume at 20:36 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

International Fa, MN (KINL), launched 12:00Z, 8.5 hours before the alert went out and 141 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, International Fa, MN at 12:00Z on 2021-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 285 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, International Fa, MN at 12:00Z on 2021-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 square meters per square second.1939587897Sfc1 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
285 J/kg
Mixed-layer CIN
-422 J/kg
Mixed-layer LCL
1229 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
190 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

021 
ACUS11 KWNS 282033
SWOMCD
SPC MCD 282032 
MNZ000-282230-

Mesoscale Discussion 1376
NWS Storm Prediction Center Norman OK
0332 PM CDT Wed Jul 28 2021

Areas affected...North-Central MN

Concerning...Severe potential...Watch possible 

Valid 282032Z - 282230Z

Probability of Watch Issuance...40 percent

SUMMARY...Isolated to scattered severe thunderstorms may develop
across north-central MN over the next few hours. Large hail and
strong wind gust are possible with any storms that do develop.

DISCUSSION...Recent surface analysis places a cold front from just
west of Lake Of The Woods County MN southwestward through southeast
North Dakota. The air mass ahead of this cold front continues to
destabilize as low-level moist advection persists. Surface
observations show temperatures have climbed into the mid 80s across
north-central MN where skies have cleared briefly. According to
mesoanalysis, this heating has eroded the convective inhibition and
at least some modest cumulus has started to build across this
region. Expectation is for isolated to scattered convective
initiation to occur along and ahead of the front. 

Steep mid-level lapse rates atop the warm and moist low-level air
mass are supporting strong buoyancy. Recent mesoanalysis suggests
MLCAPE above 2000 J/kg across the region, with higher instability
just southwest across west-central/southwest MN. Vertical shear is
also quite strong, with recent mesoanalysis estimating effective
bulk shear around 50-60 kt. These environmental conditions will
support severe thunderstorms capable of large hail and damaging wind
gusts once initiation occurs. Storm coverage remains uncertain, but
trends are being monitored closely for potential watch issuance.

..Mosier/Hart.. 07/28/2021

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

ATTN...WFO...DLH...FGF...

LAT...LON   47869617 48419563 49229520 49349491 49099474 48729462
            48499386 47739422 47049508 47339618 47869617

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 27, 7:33 PM CDTMesoscale DiscussionSPCDakota, Dodge, Fillmore, Freeborn, Goodhue, Houston and 8 more87 min
Jul 27, 8:03 PM CDTSevere Thunderstorm WatchSPCDakota, Dodge, Fillmore, Freeborn, Goodhue, Houston and 8 more6 hr
Jul 27, 10:35 PM CDTMesoscale DiscussionSPCDodge, Fillmore, Houston, Mower, Olmsted, Winona55 min
Jul 28, 2:48 AM CDTMesoscale DiscussionSPCBig Stone, Chippewa, Douglas, Grant, Kandiyohi, Lac qui Parle and 12 more2 hr
Jul 28, 10:28 AM CDTMesoscale DiscussionSPCAitkin, Beltrami, Cass, Clearwater, Hubbard, Itasca2 hr
Jul 28, 12:59 PM CDTMesoscale DiscussionSPCKoochiching, Lake, Lake of the Woods, Saint Louis2 hr
Jul 28, 5:09 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 7 more2 hr

Nearby

Mesoscale Discussions in Minnesota, 2021Every mesoscale discussion in 2021

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.