It is mustahab (preferable, praiseworthy) for men to perform fajr when there is more brightness in the sky. For women it is mustahab when it is not yet bright.
In summer zuhr salaat should be performed at a time when the day is cooler, and should be hasten in winter, except when it is overcast.
It is permissible to delay the asr as long as the sun does not change color (becomes yellow). To delay more than this is highly disliked. In overcast conditions asr should be hastened.
Maghrib should also be hastened except when overcast. Read more... (152 words, estimated 36 secs reading time)