For those that live there or have been there during that time.
Most Helpful Guy
Some of the people giving you answers on here don't know what they are talking about. London is in fact one of the driest cities in Europe . Surprisingly, it is drier than Rome, Barcelona, Paris or Berlin and it is getting drier every year. For example, March 2015 only had 1 day of measurable rain, compared to Barcelona's 16 days. And if we do get any rain at this time of year, it is very, very light so an umbrella won't be needed! Remember, London isn't in the tropics! Heavy downpours only occur in the summer months, which is ironically much wetter than it is in March! Generally speaking though, London receives around 1 inch of rain in March, which is still considerably low.
March in London is a transitional month between winter and spring so temperatures will still be considered cold, although not freezing. Lows of 3C and highs of 10C (38-52F) are the norm but it can fluctuate a few degrees either side. In recent years, March has seen temperatures fall as low as -4C and rise as high as 21C (26-70F). Generally speaking though, it will be chilly and a coat will be needed, particuarly at night. Most people don't realise this, but from October-April, London is both the warmest and driest European city outside of the Mediterranean.0