Update: Mansbridge & Woodmill alert upgraded to 'flooding is expected' warning 5.42 Oct 28
It’s thought the Yellow ‘more rain’ weather warning this weekend, an ongoing flood alert for Mansbridge and Riverside Park, and particularly high tides could cause flooding on city routes, including the A27 at Mansbridge and Woodmill Lane.
Pic from 2021

You can keep in touch with flood alerts and warnings relevant to Southampton from this link. on this page. Tide times are here.

The Met Office Yellow warning, which has been pushed back to the end of Sunday (Oct 29) is here.