Early areas of clouds cleared to reveal a fine day this morning (Saturday). The Met Office forecast 'plenty of sunshine and light winds' throughout the day.
It is very warm for many in Sussex, with temperatures peaking at 24 degrees Celsius.
Met Office meteorologist Aidan McGivern said Saturday 'could be the warmest day of the year so far, across the UK'.
Cloud and sporadic rain and showers are likely to spread northeast during the evening. Some of this will be on the heavy side, 'with a risk of thunder'. Temperatures will drop as low as seven degrees Celsius.
The sun is set to disappear on Sunday but it will stay warm.
The Met Office predicts a cloudy day, with outbreaks of rain and showers at first, 'perhaps with thunder'.
These conditions should gradually move away to the north, 'leaving a drier and warmer afternoon'. Albeit quite breezy, the maximum temperature will be 25 degrees Celsius.
The Met Office said parts of the South East could potentially reach top temperatures of 25 to 27 degrees Celsius next week.
In Sussex, temperatures will peak at 21 this week.
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