Alert archive / Nebraska / Mesoscale Discussions in 2018

Mesoscale Discussion 989

July 2, 201813 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Jul 2, 2018, 8:52 PM CDT for 13 counties in Nebraska. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
Jul 2, 2018, 8:52 PM CDT (01:52 UTC)
Expired
Jul 2, 2018, 10:15 PM CDT
In force
83 min
Issued by
the Storm Prediction Center

Counties Blaine County, NE, Buffalo County, NE, Custer County, NE, Dawson County, NE, Garfield County, NE, Hooker County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, McPherson County, NE, Sherman County, NE, Thomas County, NE, Valley County, NE

The radar

The North Platte radar (KLNX), 55 km from the middle of the area, began a volume at 01:55 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 1.9 hours before the alert went out and 53 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, N. Platte/Lee Bi, NE at 00:00Z on 2018-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3199 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 00:00Z on 2018-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 square meters per square second.193958Sfc1 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
3199 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1351 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
310 m²/s²
Significant tornado parameter
2.5
Supercell composite
24.3

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 2, 11:08 PM CDTMesoscale DiscussionSPCLogan, McPherson, Thomas67 min
Jul 3, 5:42 PM CDTSevere Thunderstorm WatchSPCDawes, Sioux7 hr

Nearby

Mesoscale Discussions in Nebraska, 2018Every mesoscale discussion 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.