Alert archive / Georgia / Mesoscale Discussions in 2017

Mesoscale Discussion 818

May 23, 20174 states

The Storm Prediction Center issued this mesoscale discussion at May 23, 2017, 4:50 PM EDT for 4 states. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: May 23, 2017, 4:50 PM EDT (20:50 UTC)
Expired: May 23, 2017, 6:15 PM EDT
In force: 85 min
Issued by: the Storm Prediction Center

All 48 counties

Baker County, FL, Hamilton County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Nassau County, FL, Wakulla County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Bryan County, GA, Bulloch County, GA, Camden County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Coffee County, GA, Echols County, GA, Effingham County, GA, Evans County, GA, Glynn County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Pierce County, GA, Screven County, GA, Tattnall County, GA, Ware County, GA, Wayne County, GA, Bladen County, NC, Brunswick County, NC, Columbus County, NC, New Hanover County, NC, Pender County, NC, Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Clarendon County, SC, Colleton County, SC, Dorchester County, SC, Georgetown County, SC, Hampton County, SC, Horry County, SC, Jasper County, SC, Marion County, SC, Williamsburg County, SC

The radar

The Charleston,SC radar (KCLX), 70 km from the middle of the area, began a volume at 20:50 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, 8.8 hours before the alert went out and 155 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: 403 J/kg
Mixed-layer CIN: -35 J/kg
Mixed-layer LCL: 774 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
May 23, 9:38 AM EDT	Mesoscale Discussion	SPC	Calhoun, Gadsden, Holmes, Jackson, Leon, Okaloosa and 2 more	2 hr
May 23, 10:10 AM EDT	Tornado Watch	SPC	Bay, Calhoun, Franklin, Gadsden, Gulf, Hamilton and 9 more	8 hr
May 23, 12:22 PM EDT	Mesoscale Discussion	SPC	Calhoun, Gadsden, Jackson, Jefferson, Leon, Liberty and 1 more	83 min
May 23, 2:45 PM EDT	Tornado Watch	SPC	Hamilton	8 hr
May 23, 2:02 PM EDT	Mesoscale Discussion	SPC	Appling, Atkinson, Bacon, Ben Hill, Berrien, Bleckley and 45 more	118 min

Nearby

Mesoscale Discussions in Georgia, 2017 Mesoscale Discussions in South Carolina, 2017 Mesoscale Discussions in Florida, 2017 Every mesoscale discussion in 2017

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.