Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
The preferred opinion is that the rules of traveling start when the person goes beyond the location or the area where he lives. So, it is not allowed for him to break the fast within that area because he may be confronted with an unexpected circumstance that forces him to stay.
Responding to your question, Dr. `Abdur-Rahman Al- `Adawi, Professor of Fiqh at Al-Azhar University, states the following:
The Prophet (peace and blessings be upon him) said, “Islam is built upon five pillars: testifying that there is no god except Allah and that Muhammad is the Messenger of Allah, performing Prayer, paying the zakah, making the pilgrimage to the Sacred House (Hajj), and fasting the month of Ramadan.”(Al-Bukhari and Muslim)
Almighty Allah says, “… and whosoever of you is sick or on a journey, (let him fast the same) number of other days. Allah desire for you ease; He desire not hardship for you; and (He desires) that ye should complete the period, and that ye should magnify Allah for having guided you, and that peradventure ye may be thankful.” (Al-Baqarah 2:185)
In this verse, Almighty Allah makes it lawful for the traveler to break the fast in Ramadan. The Prophet (peace and blessings be upon him) is reported to have said, “Allah has waived meaning half of the prayer and fasting for the traveler, and from pregnant women and the sick.” (An-Nasa’i)
Consequently, breaking the fast during the month of Ramadan is allowed for the traveler, but if someone finds that he is capable of fasting, fasting would be better, as Hamzah Al-Aslami once asked the Prophet (peace and blessings be upon him), “O Messenger of Allah, I feel able to fast when traveling, will I be sinful (if I fast while traveling)?” The Prophet (peace and blessings be upon him) said, “It is a dispensation from Allah, he who makes use of it does good and he who likes to fast, there is no blame on him.” (Muslim)
The dispensation for breaking the fast (is the same as that) for shortening the prayer, that is the distance of traveling should be (at least) 85 km (53 mi). Besides, someone is not regarded as a traveler unless he goes beyond the inhabited area of the location where he lives. So, someone who intends to travel but neither starts the journey nor goes beyond his area is not permitted to break the fast.
If someone who finds that it is difficult to go on fasting while traveling or that fasting will physiologically harm him, it is better for him to break the fast. Jabir (may Allah be pleased with him) is reported to have said, “Once the Prophet (peace and blessings be upon him) passed by a man lying under a tree while water was being sprayed at his face (because of what he was feeling due to fasting). The Prophet asked, ‘What about this man?’ They said, ‘He is fasting.’ The Prophet (peace and blessings be upon him) said, ‘Fasting is not recommended while traveling.’” (An-Nasa’i)
Breaking the fast is better than fasting if the traveler is among the Muslim army. In such a case, fasting is not preferred, especially if it physiologically weakens him so that he may not be able to join the battle.
It is allowed for the person to break the fast either in the daytime or in the middle of the day, as long as he meets the conditions for being a traveler. This is because if traveling starts in the evening and continues till the daytime, it is an excuse for breaking the fast.
This is the same as if there is a reason for breaking the fast during the daytime such as illness, which is one of the two stated conditions for breaking the fast, namely, illness and traveling. Just as being affected by illness during the daytime is a reason for a person to break the fast, it is also allowed for him to break the fast in case he is traveling in the daytime. The traveler must fast the same number of days he broke in Ramadan.
Allah Almighty knows best.