هل ستمطر اليوم؟

Use it just like the English equivalent. You can say it as a standalone question. You can also add it to the start of a conversation. It works perfectly when you see dark clouds. It also works when you are planning an outing. Just raise your pitch at the end to make it a question.

Use it when you are getting dressed in the morning. Ask your roommate before they head out. Use it when you see someone carrying an umbrella. It is a great icebreaker with a taxi driver. You can also text it to a friend before a beach trip. It is practical and very common in daily life.

Do not use this in a highly scientific meteorology report. In very formal Modern Standard Arabic settings, use هل ستمطر اليوم؟. However, for 99% of life, this phrase is perfect. Don't use it if it is already pouring rain. That might make you look a bit confused! Unless, of course, you are being sarcastic.

In Egypt, rain is not an everyday occurrence. When it does rain, it is a big event. People often get excited or worried about the mud. Asking about rain shows you are planning ahead. It is a common topic for small talk. In Cairo, even a little rain can change the whole day's rhythm.

If you want to ask about tomorrow, say هتمطر بكرة؟. To ask if it's raining right now, say بتمطر؟. You might also hear في مطر؟ which means 'Is there rain?'. Egyptians also use الدنيا هتمطر؟ which literally means 'Will the world rain?'. This is a very local and charming way to put it.