Alert archive / South Carolina / Mesoscale Discussions in 2019

Mesoscale Discussion 2136

October 31, 201912 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Oct 31, 2019, 7:58 PM EDT for 12 counties in South Carolina. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Oct 31, 2019, 7:58 PM EDT (23:58 UTC)
Expired: Oct 31, 2019, 9:00 PM EDT
In force: 62 min
Issued by: the Storm Prediction Center

Counties Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Clarendon County, SC, Colleton County, SC, Dorchester County, SC, Georgetown County, SC, Hampton County, SC, Jasper County, SC, Orangeburg County, SC, Sumter County, SC, Williamsburg County, SC

The radar

The Charleston,SC radar (KCLX), 89 km from the middle of the area, began a volume at 00:05 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

Charleston AFB, SC (KCHS), launched 12:00Z, 12.0 hours before the alert went out and 27 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: 861 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 680 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 78 m²/s²
0-3 km storm-relative helicity: 100 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.3

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.

Issued	Product	Office	Counties	Lasted
Oct 31, 1:25 PM EDT	Mesoscale Discussion	SPC	Abbeville, Anderson, McCormick	2 hr
Oct 31, 3:39 PM EDT	Tornado Watch	SPC	Abbeville, Calhoun, Cherokee, Chester, Chesterfield, Clarendon and 17 more	7 hr
Oct 31, 3:54 PM EDT	Severe Thunderstorm Watch	SPC	Aiken, Allendale, Bamberg, Barnwell, Edgefield, McCormick and 1 more	5 hr
Oct 31, 6:34 PM EDT	Mesoscale Discussion	SPC	Allendale, Bamberg, Barnwell, Beaufort, Berkeley, Calhoun and 8 more	56 min
Oct 31, 6:36 PM EDT	Mesoscale Discussion	SPC	Chesterfield, Lancaster, Marlboro	114 min

Nearby

Mesoscale Discussions in South Carolina, 2019 Every mesoscale discussion in 2019

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.