Alert archive / Kentucky / Mesoscale Discussions in 2018

Mesoscale Discussion 91

February 24, 20185 states

The Storm Prediction Center issued this mesoscale discussion at Feb 24, 2018, 2:58 PM CST for 5 states. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Feb 24, 2018, 2:58 PM CST (20:58 UTC)
Expired
Feb 24, 2018, 4:00 PM CST
In force
62 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 39 counties

Clay County, AR, Craighead County, AR, Greene County, AR, Mississippi County, AR, Alexander County, IL, Massac County, IL, Pulaski County, IL, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, Trigg County, KY, Webster County, KY, Butler County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Scott County, MO, Stoddard County, MO, Dyer County, TN, Gibson County, TN, Henry County, TN, Houston County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Stewart County, TN, Weakley County, TN

The radar

The Paducah radar (KPAH), 83 km from the middle of the area, began a volume at 20:59 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Little Rock, AR (KBYH), launched 12:00Z, 9.0 hours before the alert went out and 202 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, Little Rock, AR at 12:00Z on 2018-02-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 42 joules per kilogram.LCLLFCEL10008507005003002001001 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, Little Rock, AR at 12:00Z on 2018-02-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 176 square meters per square second.1939587897117Sfc1 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
42 J/kg
Mixed-layer CIN
-186 J/kg
Mixed-layer LCL
568 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
176 m²/s²
0-3 km storm-relative helicity
196 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
Feb 24, 10:26 AM CSTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 27 more64 min
Feb 24, 11:01 AM CSTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 43 more8 hr
Feb 24, 1:39 PM CSTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 31 more2 hr
Feb 24, 3:16 PM CSTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more8 hr
Feb 24, 5:29 PM CSTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Chicot, Desha, Drew and 3 more91 min
Feb 24, 4:49 PM CSTMesoscale DiscussionSPCAdair, Allen, Barren, Boyle, Breathitt, Butler and 33 more116 min

Nearby

Mesoscale Discussions in Kentucky, 2018Mesoscale Discussions in Tennessee, 2018Mesoscale Discussions in Missouri, 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.