Alert archive / North Carolina / Severe Thunderstorm Watches in 2017

Severe Thunderstorm Watch 120

April 3, 201716 counties in North Carolina; 13 counties in South Carolina

The Storm Prediction Center issued this severe thunderstorm watch at Apr 3, 2017, 4:36 PM EDT for 16 counties in North Carolina; 13 counties in South Carolina. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 3, 2017, 4:36 PM EDT (20:36 UTC)
Expired
Apr 3, 2017, 8:40 PM EDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 29 counties

Anson County, NC, Bladen County, NC, Columbus County, NC, Cumberland County, NC, Harnett County, NC, Hoke County, NC, Johnston County, NC, Lee County, NC, Montgomery County, NC, Moore County, NC, Richmond County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Stanly County, NC, Wayne County, NC, Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Colleton County, SC, Darlington County, SC, Dillon County, SC, Dorchester County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Marlboro County, SC, Williamsburg County, SC

The radar

The Columbia radar (KCAE), 123 km from the middle of the area, began a volume at 20:36 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 3, 4:59 PM EDTSevere Thunderstorm WarningCHSColleton61 min
Apr 3, 5:15 PM EDTSevere Thunderstorm WarningILMDarlington, Florence, Marlboro60 min
Apr 3, 5:16 PM EDTSevere Thunderstorm WarningRAHAnson, Richmond29 min
Apr 3, 5:23 PM EDTSevere Thunderstorm WarningRAHMontgomery, Moore40 min
Apr 3, 5:36 PM EDTSevere Thunderstorm WarningCHSBeaufort, Colleton, Hampton, Jasper36 min
Apr 3, 5:44 PM EDTSevere Thunderstorm WarningRAHHoke, Moore, Richmond, Scotland46 min
Apr 3, 5:46 PM EDTSevere Thunderstorm WarningCHSDorchester33 min
Apr 3, 5:54 PM EDTSevere Thunderstorm WarningRAHLee, Moore36 min
Apr 3, 5:56 PM EDTSevere Thunderstorm WarningCHSCharleston, Dorchester31 min
Apr 3, 6:00 PM EDTSevere Thunderstorm WarningILMFlorence, Williamsburg60 min
Apr 3, 6:10 PM EDTSevere Thunderstorm WarningCHSBerkeley, Charleston, Dorchester65 min
Apr 3, 6:12 PM EDTSevere Thunderstorm WarningRAHCumberland, Harnett, Hoke48 min
Apr 3, 6:21 PM EDTSevere Thunderstorm WarningRAHChatham, Harnett, Lee, Moore, Wake39 min
Apr 3, 6:36 PM EDTSevere Thunderstorm WarningCHSBerkeley, Charleston, Dorchester54 min
Apr 3, 6:42 PM EDTSevere Thunderstorm WarningILMGeorgetown, Williamsburg63 min
Apr 3, 6:50 PM EDTSevere Thunderstorm WarningILMFlorence, Horry, Marion, Williamsburg55 min
Apr 3, 7:01 PM EDTSevere Thunderstorm WarningRAHCumberland, Sampson44 min
Apr 3, 7:44 PM EDTSevere Thunderstorm WarningILMBrunswick, Columbus33 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 8.6 hours before the alert went out and 151 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, Charleston AFB, SC at 12:00Z on 2017-04-03Temperature 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, Charleston AFB, SC at 12:00Z on 2017-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1059 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 3, 2:07 PM EDTTornado WatchSPCCabarrus, Mecklenburg, Rowan, Union6 hr
Apr 3, 4:00 PM EDTMesoscale DiscussionSPCAnson, Chatham, Cumberland, Harnett, Hoke, Lee and 5 more90 min
Apr 3, 6:41 PM EDTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Bladen, Brunswick, Camden and 47 more64 min
Apr 3, 10:07 AM EDTMesoscale DiscussionSPCAbbeville, Aiken, Allendale, Anderson, Barnwell, Edgefield and 5 more83 min
Apr 3, 1:42 PM EDTMesoscale DiscussionSPCAiken, Allendale, Bamberg, Barnwell, Calhoun, Edgefield and 5 more63 min

Nearby

Severe Thunderstorm Watches in North Carolina, 2017Severe Thunderstorm Watches in South Carolina, 2017Every severe thunderstorm watch 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.