  We report the discovery of a bright (J = 13.83$\pm$0.03) methane brown dwarf,
or T dwarf, by the Two Micron All Sky Survey. This object, 2MASSI
J0559191-140448, is the first brown dwarf identified by the newly commissioned
CorMASS instrument mounted on the Palomar 60-inch Telescope. Near-infrared
spectra from 0.9 - 2.35 $\micron$ show characteristic CH$_4$ bands at 1.1, 1.3,
1.6, and 2.2 $\micron$, which are significantly shallower than those seen in
other T dwarfs discovered to date. Coupled with the detection of an FeH band at
0.9896 $\micron$ and two sets of K I doublets at J-band, we propose that 2MASS
J0559-14 is a warm T dwarf, close to the transition between L and T spectral
classes. The brightness of this object makes it a good candidate for detailed
investigation over a broad wavelength regime and at higher resolution.
