A new survey, carried out by insurance claims management specialist Town & Country Assistance, found that road accidents in which rain, hail, sleet or snow was cited as a contributory factor increased year-on-year from one-in-11.5 in the winter of 1998-99 to one-in-four in the first half of the current winter.
The company's research comes after the 2002 Government report, 'Climate Change Scenarios for the UK', which found that winters were now wetter than they have been for the past 200 years.
The survey also revealed that rain-related road accidents in summer are also on the rise in Britain.
During the summer of 2002, which suffered widespread flooding, the number of accidents in which rain was cited as a factor grew to 6.9% or one-in-14. This compared to just above 5% the year before and just below 5% in the previous two years.
Rain-related accidents last summer were at 6.6%. This is in spite of the fact that the first 10 months of 2002 were the driest in the UK since 1959.
Town & Country Assistance chief executive Theodore Agnew said: 'Our survey covers motor accidents over the last five years. As such, it has to be viewed as tentative in its conclusions. Met Office surveys usually take 50 years as a significant sample.
'Nevertheless, it would seem that there is a definite increase in road accidents in which rain or snow played a significant part over the past few years.'
The survey found that the biggest problems can happen in the event of 'ferocious downpours'.
Agnew added: 'If what might be termed this 'hard rain' is indeed the source of the problem, then we would strongly advise motorists to take particular care when confronted by torrential downpours. Otherwise, there would seem to be little doubt that the numbers of rain-related motor accidents will continue to rise.'