Alert archive / North Carolina / Tornado Watches in 2018

Tornado Watch 376

September 15, 201820 counties in North Carolina

The Storm Prediction Center issued this tornado watch at Sep 15, 2018, 6:59 AM EDT for 20 counties in North Carolina. It was in force for 10 hr.

The area

The outline as issued.

The facts

Issued
Sep 15, 2018, 6:59 AM EDT (10:59 UTC)
Expired
Sep 15, 2018, 5:00 PM EDT
In force
10 hr
Issued by
the Storm Prediction Center
Strongest gust expected
60 kt

Counties Bladen County, NC, Brunswick County, NC, Columbus County, NC, Cumberland County, NC, Duplin County, NC, Greene County, NC, Harnett County, NC, Hoke County, NC, Johnston County, NC, Jones County, NC, Lee County, NC, Lenoir County, NC, Moore County, NC, New Hanover County, NC, Onslow County, NC, Pender County, NC, Robeson County, NC, Sampson County, NC, Wayne County, NC, Wilson County, NC

The radar

The Raleigh/Durham radar (KRAX), 76 km from the middle of the area, began a volume at 11:03 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
5%
One or more gusts of 65 knots or more
5%
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
20%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Sep 15, 7:31 AM EDTFlash Flood Warning EmergencyRAHJohnston, Sampson, Wayne3 hr
Sep 15, 9:42 AM EDTFlash Flood WarningMHXCarteret, Jones, Pamlico6 hr
Sep 15, 11:12 AM EDTTornado WarningILMPender23 min
Sep 15, 11:19 AM EDTTornado WarningRAHSampson26 min
Sep 15, 11:24 AM EDTTornado WarningMHXDuplin21 min
Sep 15, 11:30 AM EDTTornado WarningMHXDuplin, Jones, Onslow27 min
Sep 15, 2:57 PM EDTFlash Flood WarningMHXCarteret, Craven, Duplin, Jones, Lenoir, Onslow22 hr
Sep 15, 3:45 PM EDTFlash Flood WarningMHXCarteret, Jones, Pamlico8 hr
Sep 15, 4:34 PM EDTFlash Flood WarningMHXCarteret, Craven, Jones, Onslow, Pamlico7 hr

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 00:00Z, 11.0 hours before the alert went out and 141 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, Newport, NC at 00:00Z on 2018-09-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 522 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, Newport, NC at 00:00Z on 2018-09-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 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
522 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
546 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

315 
WWUS20 KWNS 151056
SEL6  
SPC WW 151056
NCZ000-CWZ000-152100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 376
NWS Storm Prediction Center Norman OK
700 AM EDT Sat Sep 15 2018

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southeastern North Carolina
  Coastal Waters

* Effective this Saturday morning and afternoon from 700 AM until
  500 PM EDT.

* Primary threats include...
  A couple tornadoes possible

SUMMARY...The tornado potential with Florence should remain in the
northeastern quadrant, especially in middle-outer bands that can
access at least marginal instability near the coast and inland.  The
risk should shift very slowly westward with time.

The tornado watch area is approximately along and 55 statute miles
either side of a line from 25 miles west southwest of Fayetteville
NC to 30 miles east of Jacksonville NC. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU6).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

OTHER WATCH INFORMATION...This tornado watch replaces tornado
watch number 375. Watch number 375 will not be in effect after
700 AM EDT. 

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean
storm motion vector 14040.

...Edwards

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 14, 8:01 PM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Cumberland, Dare, Duplin and 18 more119 min
Sep 14, 10:25 PM EDTMesoscale DiscussionSPCBladen, Brunswick, Carteret, Columbus, Craven, Cumberland and 11 more95 min
Sep 14, 11:03 PM EDTTornado WatchSPCBladen, Brunswick, Carteret, Columbus, Craven, Cumberland and 12 more8 hr
Sep 15, 2:59 AM EDTMesoscale DiscussionSPCBladen, Brunswick, Carteret, Columbus, Craven, Cumberland and 12 more91 min
Sep 15, 6:15 AM EDTMesoscale DiscussionSPCBeaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 16 more90 min
Sep 15, 12:01 PM EDTMesoscale DiscussionSPCBladen, Brunswick, Columbus, Craven, Cumberland, Duplin and 9 more119 min
Sep 15, 3:26 PM EDTMesoscale DiscussionSPCPender64 min
Sep 15, 4:38 PM EDTTornado WatchSPCBladen, Brunswick, Columbus, Cumberland, Hoke, New Hanover and 4 more6 hr

Nearby

Tornado Watches in North Carolina, 2018Every tornado watch 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.