What happens to the Eid prayer if it rains?

Outdoors is the sunnah, indoors is fine

The Prophet ﷺ normally prayed Eid in an open prayer ground (musalla) outside the town, starting the day with the prayer (Sahih al-Bukhari 956). That's why many communities in Europe and the USA book parks or sports fields for Eid. But scholars agree that bad weather is a valid reason to pray inside. A narration in Sunan Abi Dawud describes the Prophet ﷺ praying Eid in the mosque on a rainy day; its chain is considered weak, but the rule itself is agreed on.

What usually happens in practice

• Plan B venues. Most organisers have a backup, such as the main mosque, a school hall or a sports centre.
• Several shifts. Indoor spaces are smaller, so the mosque may hold two or three Eid prayers in a row.
• Last-minute updates. Changes are often posted the night before or early in the morning on the mosque's website, WhatsApp group or social media.

If you've never prayed Eid before, the steps are the same wherever it's held. See How do I pray the Eid prayer?

What if the weather is really bad?

In heavy rain or storms, Islam allows people to pray at home instead of travelling to the congregation. Ibn Abbas had the caller to prayer announce "pray in your homes" on a rainy, muddy Friday, and said this was done by someone better than him, meaning the Prophet ﷺ (Sahih al-Bukhari 901). Many scholars apply the same ease to Eid. If you miss the congregation, you can pray two rak'ahs at home. See What if I miss the Eid prayer?

Rain is a blessing, too

Rain on Eid isn't bad luck. It's a mercy from Allah and a good time for dua. When you see it, say "Allahumma sayyiban nafi'an" (O Allah, make it a beneficial rain). See What dua do I say when it rains?