Alert archive / North Carolina / Tornado Watches in 2018

Tornado Watch 372

September 13, 201815 counties in North Carolina

The Storm Prediction Center issued this tornado watch at Sep 13, 2018, 8:59 PM EDT for 15 counties in North Carolina. It was in force for 10 hr.

The area

The outline as issued.

The facts

Issued
Sep 13, 2018, 8:59 PM EDT (00:59 UTC)
Expired
Sep 14, 2018, 6:58 AM EDT
In force
10 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt

Counties Beaufort County, NC, Carteret County, NC, Craven County, NC, Dare County, NC, Duplin County, NC, Greene County, NC, Hyde County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, Onslow County, NC, Pamlico County, NC, Pitt County, NC, Tyrrell County, NC, Washington County, NC

The radar

The Morehead City radar (KMHX), 75 km from the middle of the area, began a volume at 01:03 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
30%
One or more EF2 to EF5 tornadoes
10%
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

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

IssuedProductOfficeCountiesLasted
Sep 13, 9:55 PM EDTFlash Flood WarningMHXHyde4 hr
Sep 14, 1:41 AM EDTFlash Flood WarningMHXDare, Hyde3 hr
Sep 14, 2:13 AM EDTFlash Flood WarningMHXBeaufort, Craven, Jones, Pamlico8 hr
Sep 14, 2:40 AM EDTFlash Flood Warning EmergencyMHXCarteret, Craven, Jones, Pamlico30 hr
Sep 14, 6:33 AM EDTFlash Flood WarningMHXDuplin, Lenoir20 hr
Sep 14, 6:48 AM EDTFlash Flood WarningMHXGreene, Pitt23 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, 1.0 hours before the alert went out and 75 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 2018-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 240 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 2018-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 342 square meters per square second.1939587897117Sfc1 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
240 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
571 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
342 m²/s²
0-3 km storm-relative helicity
357 m²/s²
Significant tornado parameter
0.5
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

466 
WWUS20 KWNS 140056
SEL2  
SPC WW 140056
NCZ000-CWZ000-141100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 372
NWS Storm Prediction Center Norman OK
900 PM EDT Thu Sep 13 2018

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Eastern North Carolina
  Coastal Waters

* Effective this Thursday night and Friday morning from 900 PM
  until 700 AM EDT.

* Primary threats include...
  A couple tornadoes possible

SUMMARY...A moist air mass and strong low-level wind field on the
periphery of Hurricane Florence will continue to support the
possibility of transient supercells with a brief tornado risk
through the early morning hours of Friday.

The tornado watch area is approximately along and 55 statute miles
east and west of a line from 75 miles northeast of New Bern NC to 25
miles southeast of Jacksonville NC. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU2).

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...CONTINUE...WW 371...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 08060.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 13, 8:25 PM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Hyde, Jones, Onslow and 1 more2 hr
Sep 14, 12:56 AM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Dare, Duplin, Greene and 9 more3 hr
Sep 14, 6:02 AM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Dare, Duplin, Hyde and 9 more88 min
Sep 14, 6:58 AM EDTTornado WatchSPCBeaufort, Bertie, Carteret, Chowan, Craven, Dare and 20 more10 hr
Sep 14, 11:26 AM EDTMesoscale DiscussionSPCBeaufort, Bertie, Camden, Carteret, Chowan, Craven and 19 more2 hr
Sep 14, 3:42 PM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Duplin, Edgecombe, Greene and 10 more2 hr
Sep 14, 4:48 PM EDTTornado WatchSPCBeaufort, Carteret, Craven, Cumberland, Duplin, Edgecombe and 13 more6 hr
Sep 14, 7:09 PM EDTMesoscale DiscussionSPCAlamance, Caswell, Durham, Granville, Halifax, Northampton and 4 more2 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.