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In the 1990s, the number of the observed bright cloud features grew considerably partly because new high resolution imaging techniques became available.[17] Most were found in the northern hemisphere as it started to become visible.[17] An early explanation – that bright clouds are easier to identify in the dark part of the planet, whereas in the southern hemisphere the bright collar masks them – was shown to be incorrect: the actual number of features has indeed increased considerably.[102][103] Nevertheless there are differences between the clouds of each hemisphere. The northern clouds are smaller, sharper and brighter.[103] They appear to lie at a higher altitude.[103] The lifetime of clouds spans several orders of magnitude. Some small clouds live for hours, while at least one southern cloud may have persisted since Voyager flyby.[17][98] Recent observation also discovered that cloud features on Uranus have a lot in common with those on Neptune.[17] For example, the dark spots common on Neptune had never been observed on Uranus before 2006, when the first such feature dubbed Uranus Dark Spot was imaged.[104] The speculation is that Uranus is becoming more Neptune-like during its equinoctial season.[105]

The tracking of numerous cloud features allowed determination of zonal winds blowing in the upper troposphere of Uranus.[17] At the equator winds are retrograde, which means that they blow in the reverse direction to the planetary rotation. Their speeds are from -100 to -50 m/s.[17][99] Wind speeds increase with the distance from the equator, reaching zero values near ±20° latitude, where the troposphere's temperature minimum is located.[17][63] Closer to the poles, the winds shift to a prograde direction, flowing with Uranus's rotation. Windspeeds continue to increase reaching maxima at ±60° latitude before falling to zero at the poles.[17] Windspeeds at -40° latitude range from 150 to 200 m/s. Since the collar obscures all clouds below that parallel, speeds between it and the southern pole are impossible to measure.[17] In contrast, in the northern hemisphere maximum speeds as high as 240 m/s are observed near +50 degrees of latitude.