The Roads with the Worst Driving Weather

Bad or extreme weather can make driving more dangerous and is a common cause of car insurance claims. As car insurance specialists, we understand the risks these weather conditions create, from heavy rain, floods and ice to poor visibility, wind and even hot weather. Which got us wondering, which cities globally have the worst weather conditions for driving?   

To find out, we analysed meteorological data for 138 cities around the world over three years to find out which cities experience the most extreme driving weather. Our index identifies which cities have the riskiest combination of conditions across all weather categories (hot, cold, wet and windy), and as part of our scoring, we also calculated an ‘Erratic Weather Risk Score’, which assesses how much unusual weather a city has experienced in recent years, compared to its average weather readings since 2012.  

Key findings

• In the UK, Inverness is the riskiest city for driving based on the weather, and ranks 25th globally 

• Bristol, Birmingham, York and Newcastle upon Tyne all feature in the UK’s top ten cities with the riskiest driving weather 

• Dallas, Texas, is revealed as home to the riskiest weather for drivers globally, with an overall Risk Score of 72.5 out of a possible 100 

• The top five cities with the riskiest driving weather span three different continents 

The Riskiest Weather for Driving in the World  

To uncover which cities around the world are home to the riskiest weather for driving, we analysed weather data from 1st January 2023 to 31st December 2025 across 138 cities worldwide. We reviewed 12 different weather scenarios and weighted them in terms of how much they potentially increased the risk of an accident when driving and then found the number of days each city experienced each scenario, before calculating an overall Risk Score out of 100.  

Scenarios included situations such as the number of days when the windspeed reached at least 45mph, the number of days when the temperature was above 35°C and the number of days where there had been freezing temperatures after a day of rainfall.  

From hot desert cities in the Middle East to freezing climates in Canada, many cities are well prepared to handle the challenges that come with being based in a part of the world that frequently experiences extreme weather. But, whilst the cities that top the ‘Hottest’ and ‘Coldest’ roads rankings are in countries that regularly experience one type of severe climate, our overall rankings are less predictable.  

UK Driving Weather Risk Index: Top 10 Cities 

Notably, cities in Scotland top the rankings with the first non-Scottish city (Birmingham) entering in fifth place. The weather scenarios that separate Scotland from other cities in the UK are all under the ‘Erratic Weather Risk Score’ and these include things like the number of days where the temperature or rainfall are significantly outside what is expected for that location at that time of year.  

While cities in the UK may not rank highly overall in the global list of cities with the riskiest driving weather (Inverness is highest at 25^th), the high Erratic Weather Risk Scores of the UK cities show that the nation’s motorists have to deal with unseasonal leaps in temperature and weather conditions all year round. As extreme weather becomes more frequent in the UK, knowing how to prepare your vehicle and safely drive in hazardous conditions is more important than ever:  

Things to bear in mind when driving in wintry conditions:  

• Reduce your speed - stopping distances can be up to ten times longer on ice, so it’s important to leave plenty of room between you and the vehicle in front, and drive more slowly to allow yourself room for the extra distance needed for stopping. 

• Pack an emergency kit - a torch, blanket, phone charger and ice scraper are all handy to have if you break down in the winter, so make sure they’re packed, even for what should be a short journey. 

• Check your tyres - though the legal tread depth for tyres in the UK is 1.6mm, a depth of around 3mm or more is recommended for good grip in the winter. If you know your tyres are carrying a lot of wear, it may be worth getting them replaced ahead of the winter months. 

 Things to bear in mind when driving in hot conditions:  

• Monitor the hot air vitals: Monitoring tyre pressures helps prevent blowouts on hot roads, and regularly checking oil and coolant levels can help you avoid your car (and passengers) overheating. 

• Stay hydrated: At 35°C, reaction times can slow by up to 20%, while fatigue and dehydration can significantly impact our ability to focus. As well as carrying plenty of bottled water in the car to stay hydrated, drivers can make use of windscreen shades when parked to help prevent their car from accumulating heat while stationary; this also helps to protect the dashboard and steering wheel, which can both become damaged after prolonged heat exposure.  

• Get familiar with your air-con: It’s worth brushing up on the intricacies of your air-conditioning system before hot weather hits and making sure it’s re-gassed if needed. Simple tweaks to the use of the recirculation button can also have a significant impact on how effectively a car can cool and save fuel at the same time. 

Things to bear in mind when driving in wet and windy conditions: 

• Keep more distance between you and the car in front: Rain has a significant impact on stopping distances – the distance a car travels between a driver noticing a hazard and reaching a complete stop. While ice causes this to increase up to ten-fold, the distance can roughly double during wet conditions, or even longer if standing water causes a vehicle to aquaplane. As a result, drivers should double the standard advice of leaving a two-second gap to the vehicle in front, or more if the visibility is poor.  

• Don’t enter flood water if you don’t know how deep it is: Just six inches of water can be enough to cause serious engine damage. Even a small amount – as little as an egg cupful - can be sucked into the air intake and cause an engine to stall or shut off entirely. 

• Give lorries and bikes room on windy days: As well as avoiding exposed roads such as high bridges and high coastal roads, during high winds, drivers should drive slower and give plenty of space to lorries, motorbikes and caravans.  

Global Driving Weather Risk Index: Top 25 Cities  

The overarching trend in the top 25 is that there is not much trend at all. There is no recurring distribution pattern among the four different weather scenario categories; each city in the top 25 has got there based on a completely unique score combination. For example, Boston and Chicago hold the two highest scores for Cold Weather but have modest Erratic Weather scores, whilst Kuala Lumpur’s inclusion is down to its high Erratic and Hot Weather scores.  

When taking into consideration multiple types of difficult driving weather, it’s Dallas in Texas, United States, that takes the top spot with an overall Risk Score of 72.5 out of a possible 100. Dallas ranks top for the Wet/Windy category and 8^th for cities with the Hottest Weather (see Appendix), and its high scores across all four weather scenario categories puts the city as the riskiest overall weather-wise. 

Despite eight of the top 15 riskiest locations being found in the U.S., the top five span cities in three continents, with Japan’s Osaka ranking second (70 out of 100) and Bucharest, Romania and Florence, Italy, placing in fourth and fifth.  

There are fewer than 10 points separating the top 25 cities’ overall score, which shows difficult driving conditions brought about by severe weather is a widespread global issue, rather than something only felt by a handful of outlier cities. 

Alicia Hempsted, MoneySuperMarket’s Car Insurance Expert, says:

“When it comes to the UK cities with the riskiest driving weather, what stands out is how consistent the risk is across the whole of the UK. Whilst Scottish cities take the top positions, there is only seven points’ difference between the top ten, which shows that risky weather isn’t isolated to just one or two areas in the UK – it’s something all drivers need to be aware of.  

“While the British are often stereotyped as being weather-obsessed, these findings highlight just how much of an impact the weather can have on our daily lives and that the UK has some of the most unpredictable weather in the world. 

“Unpredictable weather can create hazardous driving conditions anywhere in the UK. That's why we're encouraging drivers to plan ahead and take extra care, rather than assuming bad weather is only a concern in some regions.” 

Methodology 

To uncover the world’s riskiest cities for drivers, according to the weather, MoneySuperMarket analysed three years of daily weather data (1st January 2023 - 31st December 2025) across 138 cities worldwide. Each city was scored across four categories, each worth 25 points, which were then combined to form an Overall Weather Risk Score out of 100.   

• Cold Weather Risk Score 

  • Wet freeze days - Number of days when temperatures crossed below 0°C after at least 1 mm of rain in the previous 24 hours and remained below freezing for at least two consecutive hours. 

  • Freezing days - Number of days when the minimum temperature fell below 0°C. 

  • Sub zero rain days - Number of days with at least 0.2 mm of rain in subzero temperatures. 

  • Snow days - Number of days with at least 0.5 cm of snowfall. 

• Hot Weather Risk Score - Number of days when the maximum temperature reached at least 35°C. 

• Wet/Windy Weather Risk Score 

  • Dry spell breaking heavy rain days - Number of dry-spell-breaking days that also recorded at least 7.5 mm of rain in one hour. 

  • Heavy rain days - Number of days with at least one hour recording 7.5 mm or more of rain. 

  • Extreme rainfall days - Number of days with total rainfall of at least 50 mm. 

  • High wind days - Number of days when the maximum wind gust reached at least 45 mph. 

• Erratic Weather Risk Score 

  • Anomalous hot days - Number of days when the maximum temperature exceeded the 95th-percentile of days within 15 days of the given date, over 2012-2022. 

  • Anomalous cold days - Number of days when the minimum temperature fell below the 5th-percentile of days within 15 days of the given date, over 2012-2022. 

  • Anomalous wet days - Number of days when rainfall exceeded the 95th percentile of wet days only within 15 days of the given date, over 2012-2022. 

Datapoints were percentile-ranked across the full dataset before scoring, allowing cities to be scored against one another rather than against fixed thresholds.   

Appendix 

European Driving Weather Risk Index: Top 10 Cities 

European results: Bucharest tops the European cities for risky driving, with a weather pattern similar to Budapest, that sees the cities enduring extreme cold driving temperatures as well as high heat conditions, whilst Milan and Lyon in Western Europe garner their place in the top ten due to the risk from severe wet and windy weather. The UK’s entries, Glasgow and Inverness, are included thanks to their mix of high Cold Weather Risk scores and incredibly high Erratic Weather Risk Scores. Ljubljana has fairly modest Hot and Erratic Scores but earns its place thanks to an extremely high Cold Weather Risk Score. As with the global rankings, there isn’t a vast difference in points among the top ten cities, underlining how narrow the gap is for risky driving conditions across Europe.  

North America Driving Weather Risk Index: Top 10 Cities 

North American results: All of the top ten cities with the riskiest weather for driving in North America are in the USA. The first non-US entry is Cuba’s Havana, which takes 11^th place, and Ottawa, despite its extreme winters, only reaches position 13th. Two Texan cities, Dallas and Houston, take the two top USA spots (and they also make the global top three, split by Japan’s Osaka. Despite Chicago holding the nickname of “The Windy City”, previous research has shown that the average annual wind speed in Dallas is actually higher! As the city also sits on the Great Plains, air rushes into the area when low-pressure systems form, creating high-speed winds that can be present for much of the year, though the wind tends to peak in winter and spring. Whereas the Cold Weather Risk Score vacillates quite dramatically across the nation, from Boston’s 23.4 (the highest Cold Weather Risk in North America) to just 11.5 for Florida’s Orlando, the weather category that all cities across the USA suffer from is Wet and Windy driving conditions. This risk is high for all the top ten and remains fairly consistent (with just over a four-point difference). Houston takes the crown for the US city with the most unpredictable driving weather, with a score of 15.2, whereas Boston, with an Erratic score of just 6.6, has reliably severe cold weather that drivers are more prepared for.   

Africa Driving Weather Risk Index: Top 10 Cities 

African results: Whilst Cold Weather Risk is modest to low across the continent of Africa, the majority of cities (save for Cairo and Tunis) also see fairly low to moderate risk from Hot weather driving conditions. South Africa’s Cape Town earns its place due to a high number of risky Wet and Windy days for drivers. The city with the most unpredictable weather in Africa is Tanzania’s Dar es Salaam, which scores 20.7/25 for Erratic Weather.  

 Asia Driving Weather Risk Index: Top 10 Cities 

Asian results: Osaka in Japan not only tops the Asian list of cities with the riskiest driving weather, but it takes second place in the overall global rankings with a Risk Score of 70/100. It earns its place due to a combination of a high Hot Weather Risk Score (21.4/25) and significant Wet/Windy Weather Risk Score (19.7/25). The city in Asia with the most unpredictable driving weather is Kuala Lumpur, which has an Erratic Weather Risk Score of 20.0/25, thanks to its tropical climate increasing the chances of volatile weather rather than the city being exposed to one seasonal extreme (such as Seoul with its Cold Weather Risk Score of 22.4/25). The most common weather danger for drivers across the Asian top ten is the heat-factor, with eight out of the top ten cities scoring over 20 for the Hot Weather Risk. 

 South America Driving Weather Risk Index: Top 10 Cities 

South American results: Buenos Aires takes the lead as the South American city whose climate poses the greatest risk to drivers, thanks to its high score (19.2/25) for risky wet and windy weather. Cold weather doesn’t pose a significant danger to drivers across South America, but hot temperatures are a significant risk to drivers in Rio de Janeiro, whereas Quito and Santiago earn their place in the top ten due to their unpredictable weather; both score over 17 points in the Erratic Weather Risk category. Compared to the global and other continent rankings, there is quite a large points difference for Overall Risk Score across the South American top ten. 

 Australasia Driving Weather Risk Index: Top 5 Cities 

Australasian results: Cold temperatures are virtually a non-risk for drivers in Australia and New Zealand; the dangers come from a mix of hot, wet, windy and unpredictable weather. Auckland, the only entry in the top five for New Zealand, dramatically stands apart from the Australian entries when you look at its low Hot Weather Risk Score, but it has the highest score of the five for erratic and unusual weather causing trouble for drivers. Perth takes top place, not only with the highest Hot Weather Risk Score for the continent but also the highest Wet/Windy Weather Risk Score too. 

 The Top 10 Cities for Cold Weather Risk 

Cold Weather Score results: For our analysis, as well as looking at the number of snow days (those with at least 0.5cm snowfall) and freezing days (when the minimum temperature fell below 0°C), we also counted the number of days with at least 0.2mm rain in subzero temperatures, and the number of wet freeze days, when temperatures crossed below 0°C after at least 1mm rain in the previous 24hrs, for at least two hours. Based on these conditions, Ottawa is revealed as the city with the most inclement winter weather for driving, scoring a near-perfect 24.9 out of 25 for the category. With more than 147 freezing days per year on average over the last three years, the highest of any city analysed, and 18 wet freeze days posing a high risk of black ice, the Canadian city lives up to its reputation of being one of the coldest capitals in the world. Montreal follows closely with a score of 24.6, while Helsinki, Finland, completes the top three.  

 The Top 10 Cities for Wet/Windy Weather Risk 

Wet and Windy Score results: Wet and windy weather is likely to be the weather that springs to mind for many when thinking about challenging driving conditions, but it’s not just heavy rain that can be a problem; it’s also the conditions in which it falls. For example, heavy rain after a long dry spell creates more challenging conditions than usual, as oil accumulates on the road’s surface, creating a ‘slick’ effect when finally becoming wet. As a result, we’ve combined four different wet/windy weather conditions for this metric: heavy rain days (those with at least one hour recording 7.5mm or more of rain), extreme rainfall days (with total rainfall of at least 50mm), high wind days (with maximum gusts reaching at least 45mph) and dry-spell breaking days, when at least 7.5mm rain is recorded in one hour.  

 The Top 10 Cities for Hot Weather Risk 

Hot Weather Score results: Our barometer for a city with hot weather that can create increased risk on the road is simple: those with the most days of the year when the temperature reaches at least 35°C. In general, 30°C is the point at which temperatures start to become risky for driving, not just due to the impact on the roads and vehicles, but also on the driver themselves, while these risks increase even more sharply once the 35°C barrier is reached. Our data shows that Riyadh in Saudi Arabia experiences the highest hot weather risk in the world, with more than 177 days per year on average recording temperatures of 35°C or more. All of the top five cities can be found in the Middle East, with Doha, Abu Dhabi, Dubai and Cairo all recording more than 131 days per year with this level of searing heat - though temperatures can often reach 42°C to 45°C in these locations during the summer months. With a hot desert climate, Las Vegas in the United States also ranks highly (6th) for hot weather risk, with a score of 24.1 out of a possible 25, while Delhi, India, ranks 7th, with Dallas in 8^th.  

 Erratic Driving Weather Index: The Top 10 Cities 

Erratic Weather Score results: As part of our scoring, we’ve also calculated an ‘Erratic Weather Risk Score’, which looks at how much unusual weather a city has experienced in recent years, compared to the average weather for that location since 2012. We included this measure because it can be assumed that cities that rank highly for consistent seasonal extremes, like very hot or cold weather, are likely to be more prepared for driving dangers when the weather is predictable. Drivers in these cities will have experience and measures in place for safer driving in harsh weather, for example, Canadian drivers who regularly deal with sub-zero winters will usually swap to winter tyres with better grip for navigating slippery roads, and also ensure they carry a few more winter essentials with them on their journeys, such as a small shovel, a bag of sand, extra windscreen washer fluid and extra warm layers such as gloves, a hat and a blanket.  

The results above show the cities that are most likely to be caught out and unprepared for dangerous driving weather, and when looking at this metric, seven of the top 10 locations that are likely to be least prepared for the weather conditions in their area are from the UK, with Aberdeen ranking highest with a score of 21.1 out of 25. Inverness follows closely in second (with a score of 21.0), while Glasgow (20.2) and Edinburgh (20.0) also rank in the top six.