WISE J085510.83–071442.5 was recently discovered as the coldest known brown dwarf based on four epochs of images from the Wide-field Infrared Survey Explorer and the Spitzer Space Telescope. We have improved the accuracy of its parallax measurement by obtaining two additional epochs of Spitzer astrometry. We derive a parallactic distance of 2.31?± 0.08?pc, which continues to support its rank as the fourth closest known system to the Sun when compared to WISE J104915.57–531906.1 AB (2.02?± 0.02 pc) and Wolf 359 (2.386?± 0.012?pc). The new constraint on the absolute magnitude at 4.5 μm indicates an effective temperature of 235-260?K based on four sets of theoretical models. We also show the updated positions of WISE J085510.83–071442.5 in two color-magnitude diagrams. Whereas Faherty and coworkers cited its location in M W2 versus J – W2 as evidence of water clouds, we find that those data can be explained instead by cloudless models that employ non-equilibrium chemistry.
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