Alert archive / Tennessee / Mesoscale Discussions in 2004

Mesoscale Discussion 935

May 27, 200412 counties in North Carolina; 17 counties in Tennessee; 8 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at May 27, 2004, 3:28 AM EDT for 12 counties in North Carolina; 17 counties in Tennessee; 8 counties in Virginia. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
May 27, 2004, 3:28 AM EDT (07:28 UTC)
Expired
May 27, 2004, 5:00 AM EDT
In force
92 min
Issued by
the Storm Prediction Center
All 37 counties

Alexander County, NC, Alleghany County, NC, Ashe County, NC, Avery County, NC, Burke County, NC, Caldwell County, NC, Haywood County, NC, Madison County, NC, Mitchell County, NC, Watauga County, NC, Wilkes County, NC, Yancey County, NC, Campbell County, TN, Carter County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Washington County, TN, City of Bristol, VA, City of Norton, VA, Grayson County, VA, Lee County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Washington County, VA

The radar

The Knoxville radar (KMRX), 87 km from the middle of the area, began a volume at 07:29 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, 7.5 hours before the alert went out and 234 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 2004-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 946 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 2004-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 122 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
946 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
1550 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
122 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.3
Supercell composite
5.3

Open this sounding in Storm Lab

The text

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

134 
ACUS11 KWNS 270728
SWOMCD
SPC MCD 270728 
NCZ000-VAZ000-TNZ000-KYZ000-270900-

MESOSCALE DISCUSSION 0935
NWS STORM PREDICTION CENTER NORMAN OK
0228 AM CDT THU MAY 27 2004

AREAS AFFECTED...EXTREME SERN KY...EXTREME SWRN VA...EXTREME NWRN
NC...PORTIONS NERN TN

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 270728Z - 270900Z

LINE OF TSTMS SHOULD MOVE ACROSS HIGHEST TERRAIN INVOF VA/KY BORDER
BY 8Z WITH POTENTIAL FOR OCCASIONAL DAMAGING GUSTS -- ESPECIALLY ON
NW-FACING SLOPES OF RIDGES.  ACTIVITY IS EXPECTED TO WEAKEN
THEREAFTER BUT MAINTAIN SOME STRONG -- POSSIBLY DAMAGING -- WIND
POTENTIAL SSEWD INTO MOUNTAINS OF TN/NC BORDER REGION. WW NOT
ANTICIPATED BECAUSE OF SMALL AREA AFFECTED AND FCST WEAKENING TREND.

FORWARD-PROPAGATION AND FORCED ASCENT ALONG LEADING OUTFLOW SLOPE IS
HELPING TO MAINTAIN THIS ACTIVITY DESPITE MARGINAL BUOYANCY --
ELEVATED MUCAPE LESS THAN 500 J/KG -- AND RELATIVELY STABLE LAYER OF
50S/LOW 60S SFC TEMPS. COMPLEX WILL CONTINUE TO MOVE INTO
PROGRESSIVELY MORE STABLE AIR MASS AND SHOULD WEAKEN ACROSS
MOUNTAINOUS AREA OF NERN TN/NWRN NC.

..EDWARDS.. 05/27/2004

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

ATTN...WFO...RNK...RLX...GSP...MRX...JKL...

36668436 36758345 37048217 37098169 36848117 36258071
35918090 35778144 35558300 35828399

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 26, 9:15 PM EDTSevere Thunderstorm WatchSPCBeaufort, Bertie, Camden, Chowan, Currituck, Edgecombe and 13 more5 hr
May 26, 9:40 PM EDTMesoscale DiscussionSPCAnson, Haywood, Henderson, Jackson, Polk, Transylvania and 1 more65 min
May 26, 11:21 PM EDTMesoscale DiscussionSPCBeaufort, Camden, Chowan, Currituck, Pasquotank, Perquimans and 2 more54 min
May 26, 8:57 PM EDTMesoscale DiscussionSPCMacon, Montgomery, Robertson, Sumner63 min
May 26, 8:19 PM EDTMesoscale DiscussionSPCAmelia, Arlington, Brunswick, Caroline, Charles City, Charlotte and 33 more116 min
May 27, 3:07 PM EDTMesoscale DiscussionSPCAlbemarle, Arlington, Augusta, Buckingham, Caroline, Clarke and 42 more113 min

Nearby

Mesoscale Discussions in Tennessee, 2004Mesoscale Discussions in North Carolina, 2004Mesoscale Discussions in Virginia, 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.