Alert archive / Kentucky / Mesoscale Discussions in 2018

Mesoscale Discussion 1750

December 31, 20184 counties in Indiana; 18 counties in Kentucky

The Storm Prediction Center issued this mesoscale discussion at Dec 31, 2018, 3:16 PM EST for 4 counties in Indiana; 18 counties in Kentucky. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
Dec 31, 2018, 3:16 PM EST (20:16 UTC)
Expired
Dec 31, 2018, 5:15 PM EST
In force
119 min
Issued by
the Storm Prediction Center
All 22 counties

Clark County, IN, Crawford County, IN, Floyd County, IN, Harrison County, IN, Allen County, KY, Barren County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Edmonson County, KY, Grayson County, KY, Hardin County, KY, Hart County, KY, Jefferson County, KY, Larue County, KY, Logan County, KY, Meade County, KY, Nelson County, KY, Oldham County, KY, Simpson County, KY, Spencer County, KY, Warren County, KY

The radar

The Louisville radar (KLVX), 34 km from the middle of the area, began a volume at 20:15 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

Nashville Metro, TN (KBNA), launched 12:00Z, 8.3 hours before the alert went out and 180 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, Nashville Metro, TN at 12:00Z on 2018-12-31Temperature 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, Nashville Metro, TN at 12:00Z on 2018-12-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 631 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
470 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
631 m²/s²
0-3 km storm-relative helicity
689 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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
Dec 31, 1:48 PM ESTSevere Thunderstorm WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 7 more3 hr
Dec 31, 12:22 PM ESTMesoscale DiscussionSPCCalloway, Christian, Graves, Marshall, Todd, Trigg83 min

Nearby

Mesoscale Discussions in Kentucky, 2018Mesoscale Discussions in Indiana, 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.