Snow, heavy rain and temperatures as low as minus 2C will bring Londoners an unsettled first week of the Easter school holidays.
Forecasters said daytime highs will only just get to average levels for spring.
Windy conditions and downpours will feature in most areas this week, although it will be slightly milder for the next few days with temperatures at between 12C to 14C before it turns colder again on Thursday.
The Met Office has issued a snow warning for Scotland affecting Aberdeen and Inverness from 4pm tomorrow until 11am on Wednesday with up to 6in settling on high ground and 2in at lower levels.
Met Office forecaster Tom Morgan said: “Londoners should make the most of Tuesday. We can see temperatures of 16C so it will feel relatively warm, but not as pleasant as it was a few weeks ago.
“But it’s only a brief sunny spell. The rest of the week will see showers which will become colder and windier. By Thursday and Friday, Londoners will be needing their thick coats and hats.
“There’ll possibly be wintery showers with hail and sleet. It’s a cold end to the week with overnight frosts of -2C in the most rural parts of the capital.”
Gardeners have been warned to keep an eye on their blooms as sub-zero temperatures could disrupt flowering.
Met Office meteorologist Simon Partridge said: “Typically everything started flowering and all the gardeners do need to keep an eye for the frost tonight because that will cause issues for some, I’m sure.”
A yellow weather warning put in place by national forecasters for Saturday was lifted, with conditions milder than on Friday.
Some showers are due on eastern coasts across the weekend but temperatures will generally feel less cold because of lighter winds across the country, he said.
Sunshine and dry weather could warm up most parts of the UK on Sunday but rain is likely to edge in over Northern Ireland and Scotland.
“A wetter and windier day round there and we could see some strong, possibly gale-force winds around Scotland,” Mr Partridge said.
