At the outset, the jurists mention that the entrance of Fajr is contingent on the appearance of al-ṣubḥ al-ṣādiq (the true dawn). This corresponds to the astronomical twilight, which occurs when the sun is approximately 12–18 degrees below the horizon. Based on observation of the signs of al-ṣubḥ al-ṣādiq during this timeframe, scholars differed at the exact time for it, most notably at times that align with 15 and 18 degrees. One may also refer to the following fatwa regarding the timing of Fajr.

For separate reasons pertaining to the consequential horizon (shafaq), the scholars have also differed on the entrance of ʿIshāʾ time. For further details, one may refer to the following fatwa.

Given that this is a contentious issue that is not specific to a region and applies here in the US, one should follow their local scholar or local masjid, irrespective of their region.

And Allah knows best.

Mawlana Abdullah Zaman
Student, Darul Iftaa Chicago

Reviewed and approved

Mufti Abrar Mirza
Head Mufti, Darul Iftaa Chicago