Alert archive / North Carolina / Mesoscale Discussions in 2004

Mesoscale Discussion 2313

October 13, 200423 counties in North Carolina

The Storm Prediction Center issued this mesoscale discussion at Oct 13, 2004, 7:11 PM EDT for 23 counties in North Carolina. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Oct 13, 2004, 7:11 PM EDT (23:11 UTC)
Expired
Oct 13, 2004, 9:15 PM EDT
In force
2 hr
Issued by
the Storm Prediction Center
All 23 counties

Beaufort County, NC, Carteret County, NC, Chatham County, NC, Craven County, NC, Duplin County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Greene County, NC, Harnett County, NC, Johnston County, NC, Jones County, NC, Lee County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Orange County, NC, Pamlico County, NC, Pitt County, NC, Sampson County, NC, Wake County, NC, Wayne County, NC, Wilson County, NC

The radar

The Raleigh/Durham radar (KRAX), 79 km from the middle of the area, began a volume at 23:13 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

Newport, NC (KMHX), launched 12:00Z, 11.2 hours before the alert went out and 101 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 12:00Z on 2004-10-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 272 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 12:00Z on 2004-10-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 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
272 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
881 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

067 
ACUS11 KWNS 132312
SWOMCD
SPC MCD 132311 
NCZ000-140115-

MESOSCALE DISCUSSION 2313
NWS STORM PREDICTION CENTER NORMAN OK
0611 PM CDT WED OCT 13 2004

AREAS AFFECTED...ERN NC

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 132311Z - 140115Z

AN ISOLATED TORNADO THREAT WILL CONTINUE ACROSS ERN NC OVER THE NEXT
HOUR OR TWO. HOWEVER...DECREASING INSTABILITY SHOULD ALLOW THE
SEVERE THREAT TO DIMINISH EARLY THIS EVENING.

SEVERAL SUPERCELLS ARE ONGOING ACROSS NRN AND ERN NC ALONG AND SOUTH
OF A WARM FRONT EXTENDING EWD FROM A SFC LOW. THESE STORMS WILL
CONTINUE TO MOVE ENEWD ALONG AN INSTABILITY GRADIENT WHERE 0-6 KM
SHEAR VALUES RANGE FROM 40 TO 50 KT. THIS COMBINED WITH RELATIVELY
LOW LCL HEIGHTS AND STRONG LOW-LEVEL SHEAR...WILL CONTINUE TO
SUPPORT ROTATING CELLS AND A TORNADO WILL BE POSSIBLE OVER THE NEXT
HOUR. HOWEVER...OBJECTIVE ANALYSIS SHOWS INSTABILITY IS WEAK ACROSS
ERN NC WITH MLCAPE VALUES RANGING FROM 250 TO 500 J/KG. THE
INSTABILITY WILL WEAKEN FURTHER AS SFC TEMPS CONTINUE TO
COOL...ALLOWING THE SEVERE THREAT TO DECREASE ACROSS THE REGION.

..BROYLES.. 10/13/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...AKQ...MHX...RAH...RNK...

34847637 34757661 34917822 35327944 35707961 36257919
36167782 35897682 35537626

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 13, 1:00 PM EDTMesoscale DiscussionSPCBeaufort, Carteret, Craven, Dare, Hyde, Jones and 3 more90 min

Nearby

Mesoscale Discussions in North Carolina, 2004Every mesoscale discussion in 2004

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.