The detection of global weather phenomena in irradiated extrasolar hot
Jupiter planets has provided tremendous insights into their atmospheric
structure. Non-irradiated substellar atmospheres probe weather in an
entirely different regime, where global atmospheric flows result
primarily from a combination of rapid rotation and internal convection -
e.g., as in the atmosphere of Jupiter - rather than from external
forcing. Isolated brown dwarfs are ideal targets for such
investigations because they possess planet-like atmospheric dynamics,
yet have greater intrinsic brightnesses and lack nearby bright stars to
contaminate observations. I will overview recent results on
non-irradiated brown dwarf atmospheres, focussing on a finding that
large atmospheric features analogous to Jupiter's Great Red Spot are
ubiquitous in cool substellar atmospheres.
I will also discuss results on the occurrence of asteroid belts around solar neighborhood stars, as found in a recently completed study on WISE. Together with the direct characterization of exoplanetary atmospheres, resolved imaging of the frost lines and terrestrial zones of nearby planetary systems offers exciting prospects for the generation of extreme-contrast imaging telescopes.