500 MB heights, temperatures (red), isotachs (blue), and wind barbs (black) from SPC at 21Z on Tuesday, August 21, 2007 (500 PM EDT).
The shortwave trough associated with the remnants of Tropical Storm Erin can be seen across eastern Ohio and
eastern Kentucky. Note the enhanced westerly flow just ahead and south of the trough with winds up to 40 kts.
Analyzed surface temperatures (red/purple), dew points (brown/green), and wind barbs from SPC 21Z on Tuesday, August 21, 2007 (500 PM EDT).
Note the large area with temperatures in excess of 90 degrees shown in the purple contours with much of central
and south-central North Carolina experiencing temperatures around 100 degrees. At the same time surface
dew points are in the lower 60s.
Analyzed low level lapse rates in the 0-3 km layer (blue, green, orange, and red) from SPC at 21Z on Tuesday, August 21, 2007 (500 PM EDT).
A lapse rate is the rate of temperature change with height and the image below
is for the layer from the surface to around 9,000 feet. Note the surface based, low level
lapse rates shown below exceed 8 deg C/km across include much of North
Carolina with values exceeding 9 deg C/km across central North
Carolina indicating absolute instability. These extreme values
are connected to the very hot temperatures around or just above 100 degrees.
Analyzed surface based CAPE (red) and surface based CIN (shaded in blue) from SPC at 21Z on Tuesday, August 21, 2007 (500 PM EDT).
CAPE values between 1000 and 1500 J/kg are evident across much of central North Carolina.
Analyzed precipitable water (green) and wind barbs from SPC at 21Z on Tuesday, August 21, 2007 (500 PM EDT).
Precipitable water values range from 1.6 to 1.8 inches across much of central North Carolina.
NWS Composite Reflectivity Imagery from 2032Z on 21Z on Tuesday, August 21, 2007 (500 PM EDT).
The composite reflectivity imagery is from the approximate time in which the analysis imagery above is valid.