A plane flies from Prague to Larnaca. But there is very bad weather in Cyprus. There is a lot of fog and rain. The plane cannot see to land in Larnaca.
The plane waits in the sky. Then, it flies to Paphos airport instead. The weather is better in Paphos. The plane lands there. It gets more fuel.
Later, the weather is a little better. The plane flies from Paphos to Larnaca. It arrives two hours late. The passengers wait for a long time.
Bad weather can change many plane trips. It is important to be safe.