Mixed in with sunny spells there is a chance of very heavy showers and 15-25mm, and very locally in excess of 30mm of rain, could fall within an hour, bringing the risk of flooding, especially if across urban areas.
Bands of slow-moving cloud are expected to cross the county for the rest of the week, making it something of a lottery as to where the heaviest downpours will occur.
The current forecast for the weekend is cloudy but dry with the temperature edging back up to the low 20s.
The Met Office longer range forecast is that Sussex should see warmer and drier conditions.
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