Alert archive / North Carolina / Mesoscale Discussions in 2003

Mesoscale Discussion 2102

August 5, 200323 counties in North Carolina; 9 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Aug 5, 2003, 9:20 PM EDT for 23 counties in North Carolina; 9 counties in Virginia. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued
Aug 5, 2003, 9:20 PM EDT (01:20 UTC)
Expired
Aug 5, 2003, 10:15 PM EDT
In force
55 min
Issued by
the Storm Prediction Center
All 32 counties

Alamance County, NC, Chatham County, NC, Cumberland County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Granville County, NC, Halifax County, NC, Harnett County, NC, Hoke County, NC, Johnston County, NC, Lee County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Person County, NC, Richmond County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wilson County, NC, Brunswick County, VA, City of Emporia, VA, City of Franklin, VA, Greensville County, VA, Isle of Wight County, VA, Lunenburg County, VA, Mecklenburg County, VA, Southampton County, VA, Sussex County, VA

The radar

The Raleigh/Durham radar (KRAX), 38 km from the middle of the area, began a volume at 01:20 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

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 1.3 hours before the alert went out and 98 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, Greensboro/Hi Pt, NC at 00:00Z on 2003-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1051 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, Greensboro/Hi Pt, NC at 00:00Z on 2003-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 59 square meters per square second.19395878Sfc1 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
1051 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
1040 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.4

Open this sounding in Storm Lab

The text

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

775 
ACUS11 KWNS 060121
SWOMCD
SPC MCD 060120 
VAZ000-NCZ000-060215-

MESOSCALE DISCUSSION 2102
NWS STORM PREDICTION CENTER NORMAN OK
0820 PM CDT TUE AUG 05 2003

AREAS AFFECTED...SERN VA/CNTRL NC

CONCERNING...SEVERE THUNDERSTORM WATCH 843...

VALID 060120Z - 060215Z

...OVERALL SEVERE THREAT SEEMS TO BE DIMINISHING...

WITH THE LOSS OF DAYTIME HEATING...STORMS ARE GRADUALLY WEAKENING.
ALTHOUGH LARGE SCALE ASCENT REMAINS STRONG...LOW LEVEL LAPSE RATES
HAVE WEAKENED AND LATEST RADAR TRENDS INDICATE THE CLUSTER OF STORMS
FROM TDF/RDU/GSB IS MOVING THROUGH A RAIN-COOLED AIRMASS WHICH HAS
BEEN OVERTURNED PREVIOUSLY. HOWEVER...FARTHER EAST...STORMS FORMING
FROM SFQ SWWD TO ISO HAVE SOME POTENTIAL TO PRODUCE ISOLATED SEVERE
WEATHER INCLUDING SOME HAIL AND/OR WINDS WITHIN THE NEXT 1-2 HOURS.

..TAYLOR.. 08/06/2003

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

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

34987994 35438011 37037837 36907662 35007848

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 5, 8:32 PM EDTMesoscale DiscussionSPCArlington, Fairfax, Prince William, City of Alexandria, City of Fairfax, City of Falls Church and 2 more88 min

Nearby

Mesoscale Discussions in North Carolina, 2003Mesoscale Discussions in Virginia, 2003Every mesoscale discussion in 2003

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.