The weekend sunny spell is set to end with Londoners told to expect cloudy skies and rain next week.
Temperatures reached 15C in the capital yesterday, making it the warmest day of the year so far.
But the Spring weather is not expected to continue as forecasters said there may be rain showers on Sunday afternoon.
The Met Office said any patchy rain or drizzle will die out by the evening, but thickening clouds and more rain showers are forecast for Monday.
There may be some sunny spells on Tuesday, however rain is forecast again for Wednesday evening and throughout Thursday.
It is a contrast to yesterday where Britons enjoyed temperatures higher than Mediterranean hotspots such as Barcelona, Rome and Athens.
Spring Weather
Craig Snell, forecaster at the Met Office, said: "Temperatures will return to around average, with highs of 10C (50F) to 11C (51.8F), cooling off a little bit but still not cold by any means.
"As we go into Sunday night it will be cold, with temperatures close to freezing in many spots if the sky is clear.
"Next week will see quite changeable weather but nothing out of the ordinary for this time of year."
The warmest day of the year previously was recorded in Exeter on January 9 when temperatures reached 16.5C (63.5F) .
The average temperature for March is just below 12C, according to Met Office data.
