Weather conditions will change across the UK tomorrow, with heavy rain pouring into the West, while eastern areas will experience an unseasonably high of 22C.
The Met Office has issued a rain warning for the west of England, from Manchester to Plymouth and most of Wales, which will apply from 6pm today until 12pm tomorrow.
More than three inches (80 mm) could fall in six hours with thunderstorms and lightning, potentially cutting off communities with flooded roads.
However, conditions are also becoming much milder as southerly winds carry a warm and moist air mass from the western Mediterranean and northwestern Africa.
Temperatures reached 18°C (64°F). London in the afternoon before temperatures reach 22C (72F) in parts of the South East tomorrow, with moderate to high temperatures expected in other areas.
Cyclists cross the bridge over Flechs Water near Brockenhurst in the New Forest this morning
Met Office Chief Meteorologist Matthew Lehnert said; “Warm air flowing in from the south will allow temperatures to rise above average, although it will often be cloudy.
“Temperatures could reach 20°C or 21°C (70°F) in parts of south-east England on Wednesday, with mid-to-high temperatures expected in many parts of the UK. However, this warm and moist air mass carries the risk of heavy rainfall and isolated thunderstorms.
Forecasters expect further streaks of rain across the UK later this week and although temperatures will drop slightly, they will remain mild for this time of year.
Met Office deputy chief meteorologist Dan Holley said: “A low pressure system may bring strong winds to the north and west on Friday.
“This, combined with high spring tides, could result in some coastal impacts which could potentially last into the weekend on some coastlines.
“As the weekend approaches, the weather will continue to be unsettled with further rainfall at times, and by Sunday there is a chance that a particularly deep area of low pressure moving in from the Atlantic could bring more widespread strong winds, especially to northern and western areas.” . and some disruptions may occur in places.
“This low pressure system is not expected to develop until Friday off the coast of Canada, so at this stage there is still a lot of uncertainty about the strength and track of this system as it interacts with the jet stream over the weekend.
“We will be continually assessing the need to issue warnings over the coming days, so it is important to keep up to date with the latest forecasts.”
Zoe Hutin, a meteorologist at the Met Office, also said: “The main regions to be affected (with the first warning) are central Wales, South Wales, parts of southwest England and stretching as far as Cheshire and Manchester.”
“It will be a route from Manchester to Plymouth. Between 10 and 12 mm is likely to fall across the region, but a few places could see much more, potentially as much as 80 mm of rain in six hours.
“It's hard to say exactly where at the moment. The most vulnerable places will be the most central warning areas, but could be anywhere within that region. Areas most vulnerable to flooding will also be affected, especially low-lying ones.
The warnings were issued after heavy rain caused widespread flooding across the UK in September and early October.
In some counties in England, September was the wettest on record, with rainfall three times normal.
Oxfordshire and Bedfordshire experienced their wettest months on record, although most of the UK saw rain after a summer that was drier than usual.
Ms Hutin said: “The ground has had a chance to dry out so it's not like we're retaining excess flood water from previous rainfall.
“But given that some areas have already received significant amounts of rain over the last six weeks, and that this has been a particularly wet time of year so far, particularly across central England, this rainfall will not help with reservoirs being higher than usual.” for this time of year.
Most of Northern Ireland's rainfall is expected to be in rural areas in the south-east.
Ms Hutin said: “There isn't a large population in this part of Northern Ireland so it won't have a huge impact on a huge proportion of people.
“But this is a piece of land that is particularly prone to flooding, so while the rainfall may not be particularly (heavy) – we typically expect between 20 and 30mm – the area is quite low and reasonably swampy, which means this amount of rain will had a greater impact on this region.
“But in some high areas the depth can reach 50-80 mm, which is quite high for a window of six to 12 hours.”
