According to the Met Office, both East Sussex and West Sussex will begin with heavy rain that will clear at lunchtime.
The rest of the day will be cloudy and grey.
Highs of 14 degrees Celsius and lows of 11 can be expected.
Sunset will be around 17:41 in both counties.
The evening will be dry but overcast.
The rest of the Halloween weekend will be similar with rain and clouds.