The Met Office has issued a yellow warning for rain in the capital from Sunday afternoon (April 1) through Monday (April 2).
Travel disruption is likely with a risk of flooding in west London boroughs that border the Thames.
A government warning issued on Saturday (March 31) flags a risk of flooding along the Thames from Teddington Weir to Putney Bridge.
Areas at risk of flooding include Richmond, Kew, Chiswick, Putney and Hammersmith and Fulham up to Putney bridge.
West London most likely to flood:
- Putney Embankment
- Chiswick Mall and Strand on the Green
- Thames Bank at Mortlake
- Ranelagh Drive
- Friars Lane and Water Lane
- Riverside and The Embankment at Twickenham
- The Towpath below Teddington Lock
An Environmental Agency spokesman said: "The river flow at Teddington Weir is high for this time of year at 220 cubic metres per second and is rising steadily.
"We anticipate the flows to remain high for the next few days. The forecast high tide at Richmond will be 5.03am AOD at 3.45pm BST on Saturday (March 31) with a high confidence and 5.02m AOD at 4am BST on Sunday (April 12) with a high confidence.
"Astronomical tide levels are rising. The locations potentially affected by flooding are Putney Embankment (SW15), Chiswick Mall and Strand on the Green (W4), Thames Bank at Mortlake (SW14), Ranelagh Drive (TW1), Friars Lane and Water Lane (TW9), Riverside and The Embankment at Twickenham, and the Towpath below Teddington Lock."
The Met Office warns spray and flooding from heavy rain could cause difficult driving conditions and travel disruption in London.
A Met Office spokesman said: "Rain and transient hill snow will spread northwards on Sunday. Rain will become heavy and persistent later in the day and overnight before easing from the south during Monday morning. 15-25 mm of rain is likely widely, with 40-60 mm possible locally in parts of southwest England and south Wales."
They added: "There is a chance of travel delays or cancellations to train and bus services. Spray and flooding will likely lead to difficult driving conditions and some road closures. There is a chance that homes and businesses could be flooded, causing damage to some buildings, mainly across parts of southwest England."
Keep up to date with the latest news in west London via the free getwestlondon app.
You can set up your app to see all the latest news and events from your area, plus receive push notifications for breaking news.