Alert archive / North Carolina / Tornado Watches in 2020
Tornado Watch 493
The Storm Prediction Center issued this tornado watch at Sep 17, 2020, 3:06 PM EDT for 19 counties in North Carolina; Horry County, South Carolina. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 17, 2020, 3:06 PM EDT (19:06 UTC)
- Expired
- Sep 17, 2020, 11:00 PM EDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
Counties Bladen County, NC, Brunswick County, NC, Carteret County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Duplin County, NC, Greene County, NC, Hoke County, NC, Jones County, NC, Lenoir County, NC, New Hanover County, NC, Onslow County, NC, Pamlico County, NC, Pender County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Wayne County, NC, Horry County, SC
The radar
The Wilmington radar (KLTX), 85 km from the middle of the area, began a volume at 19:05 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 30%
Warnings issued inside it
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 17, 5:16 PM EDT | Tornado Warning | MHX | Pamlico | 29 min |
| Sep 17, 6:51 PM EDT | Tornado Warning | ILM | Horry | 24 min |
| Sep 17, 8:17 PM EDT | Tornado Warning | MHX | Carteret, Craven | 28 min |
| Sep 17, 9:16 PM EDT | Tornado Warning | MHX | Carteret | 14 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
Newport, NC (KMHX), launched 12:00Z, 7.1 hours before the alert went out and 115 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.
- Mixed-layer CAPE
- 226 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 646 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 95 m²/s²
- 0-3 km storm-relative helicity
- 148 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 17, 10:27 AM EDT | Mesoscale Discussion | SPC | Cumberland, Hoke, Robeson, Scotland | 2 hr |
| Sep 17, 2:33 PM EDT | Mesoscale Discussion | SPC | Bladen, Columbus, Cumberland, Duplin, Lenoir, Robeson and 1 more | 117 min |
| Sep 17, 6:54 PM EDT | Mesoscale Discussion | SPC | Bladen, Brunswick, Columbus, New Hanover, Onslow, Pender | 2 hr |
| Sep 17, 10:20 AM EDT | Tornado Watch | SPC | Aiken, Bamberg, Barnwell, Calhoun, Chesterfield, Clarendon and 15 more | 8 hr |
Nearby
Tornado Watches in North Carolina, 2020Tornado Watches in South Carolina, 2020Every tornado watch in 2020
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.