Calculating the Zawal time
In the name of Allah, the most Beneficent, the most Merciful.
There are three times during which it is not valid to perform obligatory prayers. The times are:
- The rising of the Sun until it completely rises to the height of a spears length.
- When the Sun is at its peak (zenith)
- When the Sun draws near to setting until it sets (Maraqi Falah p.73)
Saaiduna Uqbah Bin Amir Radiallahu Anhu said that the Prophet of Allah Sallallahu Alahi Wasalam used to forbid us to pray or bury our dead during three times. When the Sun begins to rise until it has completely risen, when the Sun is at its height at midday till it passes the meridian and when the Sun draws near to setting till it sets.’
(Sunan Abi Dawud)
With regards to your question Zawal means the time when the Sun moves away from its peak and this is when Zuhr time starts. Istiwa is when the Sun is at its highest peak at noon and that is when to read salah is impermissible. (Raddul Muhtar p.31 v.2)
To calculate ‘Istiwa’ it is half of the time between Sunrise and Sunset. The time when the Sun is at its peak is for a momentary period; therefore it is difficult to pinpoint the exact moment. Hence the jurists out of caution have said five minutes before and five minutes after ‘Istiwa’ time one should refrain from reading any salah. (Aapke Masaail p.144 v.2)
Only Allah Knows Best
Mohammed Tosir Miah
Darul Ifta Birmingham.