Well, the Hijri date 13 Rabi Al Awwal 1404 corresponds to the Gregorian date Saturday, 17 December 1983. This date lies in the third month of the Hijri year 1404 AH, which is Rabi Al-Awwal of 1404 AH. Both this Hijri and Gregorian date occur on the single day that is Saturday without any doubt. The Arabic date 1404/03/13 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 17 December 1983 to its equivalent Arabic date.
The following is the conversion of the Arabic date 13 Rabi Al Awwal 1404 AH to its equivalent Gregorian date.
قُلِ ٱللَّهُ يُحْيِيكُمْ ثُمَّ يُمِيتُكُمْ ثُمَّ يَجْمَعُكُمْ إِلَىٰ يَوْمِ ٱلْقِيَٰمَةِ لَا رَيْبَ فِيهِ وَلَٰكِنَّ أَكْثَرَ ٱلنَّاسِ لَا يَعْلَمُونَ
Say (unto them, O Muhammad): Allah giveth life to you, then causeth you to die, then gathereth you unto the Day of Resurrection whereof there is no doubt. But most of mankind know not.
Surah Al-Jaathiya(45:26)
Sahih al-Bukhari
Fasting
Chapter: If somebody breaks the Saum thinking that the sun has set
Narrated Abu Usama from Hisham bin 'Urwa from Fatima:
Asma bint Abi Bakr said, "We broke our fast during the lifetime of the Prophet (ﷺ) on a cloudy day and then the sun appeared." Hisham was asked, "Were they ordered to fast in lieu of that day?" He replied, "It had to be made up for." Ma`mar said, "I heard Hisham saying, "I don't know whether they fasted in lieu of that day or not."
Sahih al-Bukhari 1959