Alert archive / Minnesota / Mesoscale Discussions in 2007

Mesoscale Discussion 1829

August 21, 200712 counties in Minnesota

The Storm Prediction Center issued this mesoscale discussion at Aug 21, 2007, 2:16 AM CDT for 12 counties in Minnesota. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Aug 21, 2007, 2:16 AM CDT (07:16 UTC)
Expired: Aug 21, 2007, 3:15 AM CDT
In force: 59 min
Issued by: the Storm Prediction Center

Counties Anoka County, MN, Carver County, MN, Dakota County, MN, Hennepin County, MN, Isanti County, MN, McLeod County, MN, Meeker County, MN, Ramsey County, MN, Scott County, MN, Sherburne County, MN, Washington County, MN, Wright County, MN

The radar

The Minneapolis radar (KMPX), 11 km from the middle of the area, began a volume at 07:19 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

Minneapolis, MN (KMPX), launched 00:00Z, 7.3 hours before the alert went out and 11 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: 62 J/kg
Mixed-layer CIN: -345 J/kg
Mixed-layer LCL: 520 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 170 m²/s²
0-3 km storm-relative helicity: 271 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 20, 7:03 PM CDT	Mesoscale Discussion	SPC	Nobles, Rock	117 min
Aug 20, 10:23 PM CDT	Severe Thunderstorm Watch	SPC	Anoka, Blue Earth, Brown, Carver, Chippewa, Cottonwood and 25 more	5 hr
Aug 21, 4:50 PM CDT	Mesoscale Discussion	SPC	Blue Earth, Brown, Cottonwood, Dakota, Dodge, Faribault and 17 more	85 min

Nearby

Mesoscale Discussions in Minnesota, 2007 Every mesoscale discussion in 2007

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.