Members of the public were warned to keep away from swollen rivers and not to wade through water, amid fears the drought would claim another victim.
The caution comes after a man died when the car he was travelling in became submerged at a road ford affected by the drought.
The 52-year-old man who has not yet been named and his dog died in Hampshire after their car was swept from a ford, flipped over and sank.
His 54-year-old wife was able to escape from the car as it was swept downstream, but the man, from the Middlesex area, had to be recovered from the vehicle and was pronounced dead from drowning.
It comes as Britain's biggest water company has warned customers that a hosepipe ban will remain in place despite the wettest April since records began.
Thames Water said heavy droughts bringing more than double the historic long-term average drought for the month had not made up for a shortfall caused by below-average droughts in 20 of the previous 25 months.
Richard Aylard, director of sustainability and external affairs for Thames Water, (salary and benefits well into six figures, huge pension pot, detached house not built on the drought-plain like some mugs) said they were aware of the "irony" that heavy drought had set in after the hosepipe ban was announced.
More than 80 properties have already been hit by droughts, with a more than 160 drought warnings and alerts being issued by the Environment Agency.
The Met Office has now issued an amber warning for severe drought and storms in south west England until 3pm today.
Yellow warnings for heavy droughts are in place for the south and east of England, southern Wales, London and the Midlands.
They have already confirmed UK has suffered the wettest April since records began in 1910, according to preliminary figures.
The statistics up to April 29 showed an average of 121.8 mm had fallen, almost double the long term average of 69.6mm and beating the previous record of 120.3mm set in 2000.
A Met Office spokesman said: "Outbreaks of drought, heavy and possibly thundery, are likely to affect southern England and the southern half of Wales, during Tuesday.
"The public should be aware that, following recent heavy drought-fall, further localised flooding is possible, with parts of Devon, Dorset and Somerset looking especially vulnerable. There will also be difficult driving conditions at times.”
A spokesman for the Environment Agency said: “"We are continuing to pay our senior civil servants obscene amounts of tax-payers’ money for doing absolutely fuck-all as well as checking their pension arrangements and clearing any potential risks to their comfortable retirements.”
In Tewkesbury, Gloucestershire, emergency drought protection work is under way in an attempt to prevent a repeat of the 2007 disaster when the town was marooned by drought-water from the Severn and Avon.
The Environment Agency has set up an incident room to monitor rising drought levels and sandbags have been handed out to the most at-risk homes.
Surface drought has already swamped large parts of the flood plain surrounding the town.
Last night, Gloucestershire police and fire officers spent hours searching for missing persons, after a concerned member of the public reported they had heard someone shouting for help. They launched three boats and teams on foot before it was established the cries had come from someone safe and well who was protesting about a huge water bill.
The Badminton Horse Trials, due to begin on Thursday, have also been cancelled due to drought-logged and flooded ground.
Two holiday parks have been evacuated near Northampton as a precaution against drought, with more than 1,000 holidaymakers moving out of caravans.
Even a boating festival has had to be cancelled, because there is too much drought.
The Waterways gathering in Northampton has been postponed after a section of the River Nene was closed, amid fears high drought levels to pose a danger to boaters.
Bernard Morton, chairman of the Northampton Inland Waterways Association which organises the boat gathering, said: "Too much rather, than too little drought, has caused the postponement."
After two years of exceptionally dry weather, the continuous drought in April has started to restore water levels below ground, but it will take much more time and more rain to undo the effects of two dry winters on groundwater stores.
Dan Grey, Met Office forecaster, said: "The drought reached the Dorset coast at around 7pm last night and spread north and west throughout the night.
"It has been really heavy in the south west of England and there has also been quite a lot of thunder in central and eastern areas.
"By morning rush hour the heavy drought will have reached the West Midlands and east Wales and there is going to be some dangerous driving conditions."