Alert archive / Minnesota / Mesoscale Discussions in 2017

Mesoscale Discussion 979

June 10, 2017Lake County, Saint Louis County, Minnesota

The Storm Prediction Center issued this mesoscale discussion at Jun 10, 2017, 3:31 PM CDT for Lake County, Saint Louis County, Minnesota. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
Jun 10, 2017, 3:31 PM CDT (20:31 UTC)
Expired
Jun 10, 2017, 5:30 PM CDT
In force
119 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Lake County, MN, Saint Louis County, MN

The radar

The Duluth radar (KDLH), 73 km from the middle of the area, began a volume at 20:33 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 151 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 2017-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2017-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 882 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1069 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
882 m²/s²
0-3 km storm-relative helicity
905 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

As transmitted.

309 
ACUS11 KWNS 102031
SWOMCD
SPC MCD 102031 
MNZ000-102230-

Mesoscale Discussion 0979
NWS Storm Prediction Center Norman OK
0331 PM CDT Sat Jun 10 2017

Areas affected...MN Arrowhead

Concerning...Severe potential...Watch unlikely 

Valid 102031Z - 102230Z

Probability of Watch Issuance...20 percent

SUMMARY...Isolated thunderstorms capable of damaging wind gusts and
hail are possible during the next few hours across the MN arrowhead.
A watch is not currently anticipated.

DISCUSSION...Latest surface analysis show the frontal boundary is
located from just east of ORB southwestward through AIT. Visible
imagery shows an increasingly agitated cu field along and just ahead
of this boundary. The character of this cu field suggests convective
inhibition is eroding, which matches the most recent mesoanalysis
estimates of little remaining convective inhibition. Temperatures
have warmed into the upper 80s ahead of the front, which, when
coupled with dewpoints in the mid 60s and steep mid-level lapse
rates is supportive of MLCAPE around 1500-2000 J/kg. Additionally,
downstream kinematic profiles characterized by strong mid-level flow
(over 70 kt at 500 mb) and ample bulk shear (over 60 kt from 0-6 km
per the latest mesoanalysis) suggest the potential for storm
organization. The persistent warm mid-level temperatures and
associated capping will likely temper convective coverage and the
current expectation is for any thunderstorm activity to remain
co-located with the frontal boundary. Even so, favorable
thermodynamic and kinematic environment results in the potential for
a few damaging wind gusts and hail with any storms that do develop.
Anticipated limited spatial and temporal extent of the threat is
expected to preclude the need for a watch.

..Mosier/Bunting.. 06/10/2017

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

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

LAT...LON   47349296 48229191 48249111 47899032 46759218 46649314
            47349296

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 9, 7:08 PM CDTMesoscale DiscussionSPCClay, Kittson, Marshall, Norman, Polk67 min
Jun 9, 9:30 PM CDTMesoscale DiscussionSPCBecker, Beltrami, Clay, Clearwater, Hubbard, Kittson and 9 more60 min

Nearby

Mesoscale Discussions in Minnesota, 2017Every mesoscale discussion in 2017

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.