Alert archive / North Dakota / Severe Thunderstorm Watches in 2018

Severe Thunderstorm Watch 270

July 10, 201811 counties in North Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Jul 10, 2018, 8:50 PM CDT for 11 counties in North Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jul 10, 2018, 8:50 PM CDT (01:50 UTC)
Expired: Jul 11, 2018, 1:56 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 70 kt

Counties Bottineau County, ND, Burke County, ND, Divide County, ND, McHenry County, ND, McKenzie County, ND, Mountrail County, ND, Pierce County, ND, Renville County, ND, Rolette County, ND, Ward County, ND, Williams County, ND

The radar

The Minot AFB radar (KMBX), 114 km from the middle of the area, began a volume at 01:52 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 10%
One or more EF2 to EF5 tornadoes: 10%
Ten or more severe wind reports: 40%
One or more gusts of 65 knots or more: 40%
Ten or more severe hail reports: 10%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 50%

Warnings issued inside it

3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jul 10, 9:19 PM CDT	Severe Thunderstorm Warning	BIS	Divide, Williams	56 min
Jul 10, 10:09 PM CDT	Severe Thunderstorm Warning	BIS	Burke, Divide, Mountrail, Renville, Ward, Williams	66 min
Jul 10, 11:07 PM CDT	Severe Thunderstorm Warning	BIS	Bottineau, Burke, McHenry, Mountrail, Renville, Ward	53 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.8 hours before the alert went out and 221 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: 2638 J/kg
Mixed-layer CIN: -184 J/kg
Mixed-layer LCL: 1499 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 162 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 10, 7:32 PM CDT	Mesoscale Discussion	SPC	Billings, Burke, Divide, Dunn, Golden Valley, McKenzie and 5 more	118 min
Jul 10, 11:20 PM CDT	Mesoscale Discussion	SPC	Bottineau, Burke, McHenry, Mountrail, Pierce, Renville and 3 more	115 min
Jul 11, 6:42 PM CDT	Tornado Watch	SPC	Richland	6 hr

Nearby

Severe Thunderstorm Watches in North Dakota, 2018 Every severe thunderstorm watch in 2018

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.