Weather on other worlds: from clouds and winds to seeking life

Weather systems are now known to be ubiquitous on brown dwarfs, and probably also on all exoplanets with atmospheres.  Photometric phase mapping of rotating brown dwarfs and exoplanets reveals storm- and band-like structures, much like in the Solar System, while spectroscopic monitoring probes the altitudes of the constituent cloud layers. Polarimetric observations are further revealing the characteristic sizes of the cloud droplets.  The empirical picture of substellar atmospheres is rapidly unravelling.  The unprecedented observational precision enabling this development is also offering an interesting new possibility: to efficiently detect habitable Earth-like planets around brown dwarfs.  These may well offer the first opportunity to discover extrasolar life with JWST.