A fine September Saturday in Barnes: sunshine and 23°C
12 September 2026 · By Boroughly editorial — AI-assisted, human-reviewed.
September is delivering today, with the Met Office forecasting a sunny day across Barnes and a comfortable high of 23°C — well above the seasonal average and a welcome continuation of what has been a decent late-summer stretch.
The overnight low sits at 18°C, so it will feel mild well into the evening. The chance of rain is just 6%, making an umbrella firmly optional. UV index is rated at 5 (moderate), so a little sunscreen is worth applying if you're spending a few hours outside.
With the Open House Festival running across the borough this weekend — over 20 venues open their doors free of charge — the weather gives a genuine reason to get out and explore. Barnes Common, the riverside path along the Thames and the wetland centre all make for excellent morning or afternoon walks in these conditions.
The forecast was issued by the Met Office for Saturday, 12 September.