The Met Office expects that the temperature will remain at about 27°C to 30°C throughout the county before it drops to about 23°C from tomorrow (Tuesday, August 13).
The temperature should start to drop in the late afternoon today so people have lots of time to make the most of the sunshine.
If you’re planning a family fun day out at the beach, which one should you choose and which one should you avoid? We have picked a few of the best beaches in Sussex in this gallery below.
1. Bosham Quay
This pretty beach and village is on one of the inlets of Chichester harbour. It is a great place to visit for free, but visitors are warned that the tide can come in rather fast. Photo: Steve Robards
2. South Lancing
This shingle beach between Shoreham-by-Sea and Worthing is popular with dog walkers, sailing enthusiasts, windsurfers and kite-surfers. Photo: Steve Robards
3. Brighton Beach
This one is always a big hit on hot days as it has the Palace Pier, a great town for shopping and lots of places to eat. However, it does have a reputation for getting crowded so maybe it's not the best place for people who want peace and quiet. Photo: Jon Rigby
4. Hastings and St Leonards
People made the most of these fabulous beaches last summer with revellers seen sunbathing, kayaking and swimming in the sea. Photo: staff