Norwich Union uncovers the truth about British weather

Article date: 24 January 2006

A unique weather study by Norwich Union has found thatBritain’s reputation for rainy weather is unfounded.

Research by the UK’s largest insurer grouped motor claims andaccident information according to weather conditions for 2004 and2005. Contrary to popular belief, the research showed that, onaverage, it only rains 6.2% of the time across the UK at anyone time – although it is cloudy an additional 66% of thetime, which is probably not much of a surprise to anyone.

Weekends are the best time to get out for a drive, as there arefewer cars on the road – resulting in an increase in trafficspeed by 11%. Although the higher speed also means that collisionsare slightly more serious with repair costs on average about 10%more than for crashes on weekdays.

Julian Beardsworth, director of underwriting (personal lines),Norwich Union, said of the research: “Our research is theclearest indication yet of the extent to which bad and extremeweather impacts our driving performance. With the Met Officepredicting the coldest winter in a decade, motorists shouldremember that a little preparation before setting out on a journeycan avoid a breakdown or accident.”

The recent short-lived cold snap over the holidays is untypical ofrecent British winter weather: it is below freezing only 2-3% ofthe time – just 11 days a year. However, accidents increasemore than 50% when there has been a severe frost.

Julian says: “Frost and ice affect the vehicle’sability to grip the road properly. We also see a lot of accidentswhere drivers admit they had visibility problems. If there has beena frost, drivers need to allow enough time to defrost and scrapeall windows on their vehicle so that they can see properly. A cleanwindscreen – inside and out – is essential to clearvision. We’ve even heard of accidents where the driver hasliterally had his or her head out the window because theycouldn’t see through their own windscreenproperly!”

Although it’s not surprising that wet days result in moreaccidents than dry days, by just how much was a surprise. Accidentson the wettest days increase by 40% - a clear indication that evenin the rain, motorists are not taking proper precautions. The roadsare more congested in the rain as well, as people are 10% morelikely to drive when it’s raining.

Julian said: “Our research shows that drivers only slow downby 3–4% when it’s raining. We would urge drivers toslow down and allow extra stopping space between their vehicle andthe car in front of them, as stopping distances increase in wetweather. It is commonly acknowledged by road safety organisationsthat in dry conditions, drivers should allow two seconds’time between their vehicle and the vehicle ahead of them whentravelling at speed. This distance should be increased in wetconditions, and drivers should slow down accordingly.

“Accidents in wet conditions cost an average of 27% more thanaccidents on dry days – this is down to the greater impactspeed resulting from slick road conditions. That cost is not justdamage to the car, but also personal injury – so drivers needto beware that especially in the wet, speed kills.”

Finally, the report finds that extreme weather conditions of anytype tend to increase the number of accidents on the roads, soaringtemperatures add 40% while days with local thunderstorms or extremewindspeeds have 10% more crashes than wet days.


Results from Norwich Union’s Weather and Road SafetyStudy
Weather data from a variety of sources waspooled to support the analysis of Norwich Union's claims data. Theresults and their implications for road safety are exploredbelow:

  • Traffic speed is 11% faster at the weekend
    - Fewer cars on the road
  • The number of accidents is more than 50% higher when there hasbeen a severe frost
    - Gripping/Driveway
    - Contributory factors being visibility/poor grip
  • The amount of rainfall is a strong predictor of the number ofaccidents - the wettest days result in 40% more accidents than drydays
    - Grip/visibility/speed
    - Stopping distance
    - Avoiding puddles
    - Pedestrian behaviour
  • Drivers only slow by 3 to 4% when it's raining
  • People are 10% more likely to drive when it's raining
    - Choosing not to walk
  • Accidents in wet conditions cost an average of 27% more thanaccidents in dry conditions
    - Impact speed higher
    - Multiple collisions more likely
  • On days with snow we see 10% more accidents
    - Ability to grip the road
    - Traffic density - no evidence that it is lower
  • Thunderstorm conditions give rise to more claims than simplyrainy conditions
    - Torrential rain making roads exceptionally hazardous
    - Distraction of storm
    - Unpreparedness for change in condition

Weather results:

  • It rains about 6.2% of the time across the UK
  • It snows for one day a year in the average UK location
  • The wind comes from the Southerly to Westerly direction nearly60% of the time
  • It's cloudy 2/3rds of the time
  • Motorists slow down for rain and snow but not for mist
  • It's below 0 for about 2 to 3% of the time
  • It's above 20 degrees C (68 F) also about 2 to 3% of thetime
  • We spent an average of 200 hours below freezing in 2004
  • Most of the time the UK temperature is between 5 and 15degrees C

For more information, please contact:
Erik Nelson on 01603 682264 or 07989 427086, or via e-mail

Notes to editors:
Norwich Union carried out extensiveresearch over 2004 and 2005 from a variety of internet weatherreporting sources, logging current conditions at hundreds ofweather stations across the UK on a real-time basis.

About Norwich Union

  • Norwich Union is the UK’s largest insurer with a marketshare of around 14%
  • With a focus on insurance for individuals and smallbusinesses, Norwich Union insures:
    - one in five households
    - one in seven motor vehicles
    - more than 800,000 businesses
  • Norwich Union products are available through a variety ofdistribution channels including brokers, corporate partners suchas banks and building societies and Norwich Union Direct
  • Norwich Union’s news releases are available fromAviva’s internet press centre at

Norwich Union Insurance
The following are authorised and regulated by the FinancialServices Authority

Norwich Union Insurance Limited Registered in England No. 99122Registered Office: 8 Surrey Street Norwich NR1 3NG.
CGU Insurance plc Registered in Scotland No. 2116 RegisteredOffice: Pitheavlis Perth Scotland Pp 0NH

CGU International Insurance plc Registered in England No. 21487Registered Office: St Helen’s 1 Undershaft London EC3P3DQ

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