Composite maps from significant tornado events across the southern Appalachian region of surface isobars, 850-hPa isoheights, 500-hPa isoheights, and 250-hPa isotachs.
Figure 5. Composite maps from significant tornado events across the southern Appalachian region of (top left) surface isobars (hPa), (top right) 850-hPa isoheights (m), (bottom left) 500-hPa isoheights (m), and (bottom right) 250-hPa isotachs (m s-1).

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