If you're in the UK, then its probably about 2am till 6am.


The first third of the night is like 6pm till 10pm

second third - 10pm - 2am

and the final third is 2am - 6am.

Each with a 4hr in between time span insha'Allaah.


The above example works especially in the winter, so you can probably work it out for the rest of the seasons insha'Allaah.