  We present spectroscopy, astrometry, and photometry of the brown dwarf WISEP
J004701.06+680352.1 (W0047+68), an unusually red field L dwarf at a distance of
$12.2 \pm 0.4$ parsecs. The three-dimensional space motion identifies it as a
member of the AB Dor Moving Group, an identification supported by our
classification of W0047+68 as intermediate surface gravity (INT-G) using the
Allers \& Liu (2013) near-infrared classification system. This moving group
membership implies near-solar metallicity, age $\sim 100-125$ Myr, $M \approx
0.018~M_\odot$, and $\log g \approx 4.5$; the thick condensate clouds needed to
explain the infrared spectrum are therefore a result of the lower surface
gravity than ordinary field brown dwarfs. From the observed luminosity and
evolutionary model radius, we find $T_{eff} \approx 1300 $K, a temperature
normally associated with early T dwarfs. Thick clouds are also used to explain
the spectral properties of directly imaged giant planets, and we discuss the
successes and challenges for such substellar models in matching the observed
optical and infrared spectra. W0047+68 shows that cloud thickness is more
sensitive to intermediate surface gravity than in most models. We also present
a trigonometric parallax of the dusty L6 dwarf 2MASS J21481628+4003593. It lies
at $8.060 \pm 0.036$ parsecs; its astrometry is consistent with the view that
it is older and metal-rich.
