The complete guide to travel weather

Whether you're lured by the tropics, desert heat and dust, or a winter wonderland, there's a weather effect to suit you somewhere on the globe. The BBC weatherman Peter Cockroft offers some meteorological wisdom so you can enjoy your break - rain, hail or shine

What is the difference between 'weather' and 'climate'? We don't have a climate - just weather. You book your holiday depending on the climate, but when you arrive, there's only the weather! So what's the difference between the two? Starting with "weather": this is just what the atmosphere throws at us from day to day. "Climate", on the other hand, is what those day-to-day downpours add up to over a much longer period. That longer period is usually of the order of 30 years - in other words "climate" is the long-term summary of "weather".

What is the difference between 'weather' and 'climate'? We don't have a climate - just weather. You book your holiday depending on the climate, but when you arrive, there's only the weather! So what's the difference between the two? Starting with "weather": this is just what the atmosphere throws at us from day to day. "Climate", on the other hand, is what those day-to-day downpours add up to over a much longer period. That longer period is usually of the order of 30 years - in other words "climate" is the long-term summary of "weather".

Now, you might think "climate is just the average weather, then". But a simple average over a number of decades is going to hide some major weather events. The incidence of hurricanes can get lost in a page of wind-speed statistics. However, the likelihood of hurricanes hitting a holiday destination will have a major influence on harbour and hotel design and may even put off the more nervous traveller.

Hurricanes hardly ever happen, do they? Hurricane, typhoon or cyclone are the names given to this most destructive natural phenomena, and as far as holiday weather is concerned they should all be avoided! They originate over the tropical oceans just to the north and south of the equator where sea temperatures reach around 26C, but of course they do bump into the surrounding land masses from time to time. Even I would be tempted into seawater that warm, but you wouldn't find me anywhere near one of these brutes. (As a meteorologist I have to say they are magnificent and awe-inspiring.) In the Caribbean and the Gulf of Mexico the rhyme, "June too soon - October all over" is a pretty good guide to the main hurricane season and that holds fairly well for the eastern Pacific too. In the western Pacific and South China Sea they're called typhoons and the main season runs from April through to January. In the Bay of Bengal and Arabian Sea they're called cyclones - with May/June and October/November the times of year to avoid.

Thankfully, south of the equator they are all called tropical cyclones and there is just the one season. So if you're planning a holiday in the southern Indian Ocean or south Pacific you might want to avoid December through to April.

Having said all that, it is worth noting that any countries prone to these very powerful storms have tried-and-tested warning services. These are coupled with evacuation procedures and special storm shelters and harbours.

Does a weatherman have a rule of thumb about holiday weather? Open any half-decent atlas and you should find maps showing the differing climates across the globe and that's your first guide to holiday weather. On weather maps, you'll always find the words HIGH and LOW somewhere - this refers to the air pressure. The general guide here is: HIGH - good holiday weather, LOW - bad holiday weather.

If it's heat you're after, you might be tempted towards the equator. And while you will find some of the hottest weather in Ethiopia where temperatures average 34C or 93F, because it is a low-pressure zone you will also find rain in large amounts but short, thundery bursts. Java is a good example - it has more than 320 thundery days a year.

Heading away from the equator we run into a belt of high pressure around 25 degrees latitude and the weather is dry and sunny. How dry and how sunny? Well, the Atacama Desert in Chile has enjoyed a 400-year drought, and in the northern hemisphere parts of the Sahara have clear blue skies adding up to more than 4,000 hours of sunshine a year.

Then of course there's that wet and windy bit at around 55 degrees latitude - another low-pressure zone. That's what makes life so challenging for the UK tourist industry and ensures that holidaying at home is a bit of lottery weather-wise. The reason the weather is so changeable in this region is that it's where warm tropical air meets cold polar air. They really don't mix, and the battle between them keeps us weather forecasters in a job. However, every now and again during the summer months the tropical air will win and we'll see the classic headline "Phew - what a scorcher"; or during the winter the polar air gets the upper hand: "Big freeze continues".

And finally to the extreme extreme: to the poles where the pressure is high and it's very cold. How cold? On an annual basis the coldest place on earth is Vostok in Antarctica, which averages minus 57C. However during the winter of 1892 Verkhoyansk in Siberia, just north of the Arctic Circle, recorded a flesh-freezing minus 68C (minus 90F).

The holy grail - where in the world has the best holiday weather? If by that you mean not too hot or too cold and relatively dry with a good deal of sunshine, then you would be hard-pressed to beat southern California. San Diego's daytime temperature hovers around 20C throughout the year. Although some of the winter months can be wet there's the possibility of as much as 10 hours of sunshine a day and that goes up to 14 hours in the summer. Eilat in Israel is another possibility. Sunshine amounts are similar to San Diego's but you'd be really unlucky to get rained on there, even in the winter. The other plus is the warm water of the Gulf of Aqaba. However some might find an air temperature of 40 Celsius just too hot in mid-summer.

But there is somewhere closer that is already very popular with British holidaymakers, and good value for money... The Canaries. Yes, it can be wet and windy at times in the winter but any stormy weather is generally short-lived, and as the prevailing winds are the northeast Trades, you can escape the worst of a storm by going to the south-west of the islands. Again, you are looking at the possibility of between 10 and 14 hours of sunshine a day with temperatures throughout the year in the low twenties. Personally the only thing I'm not keen on is the chilly Atlantic - mind you there are plenty of hotel pools.

I'm a great fan of island holidays. It's easy to see what the weather is doing and if you choose one with a big hill in the middle you can usually find some protection from the worst excesses of the weather.

What effect could climate change have? Unfortunately some of the low-lying island nations around the world are under threat from rising sea levels. So if you've been planning a trip to the South Sea islands of, say, Kirabati, or you're thinking about the Indian Ocean and the Maldives, do it sooner rather than later.

Weatherwise, is there any point holidaying at home? If you decide to holiday in the British Isles, here are a few helpful hints. June tends to be the sunniest summer month, with July and August the warmest. Sea temperatures peak in late August too. Summer skies are generally cloudier inland but it's warmer than the coast. On the other hand, it's the coasts that get the lion's share of summer sunshine, and the bluest skies can be found in the Channel Islands, then the Isle of Wight followed by the south coast of England. If you're taking the car then by choosing a peninsular location you can hedge your bets to a certain extent. Cornwall is the perfect example of this - if a northerly wind is blowing sea fog on to the coast at Newquay you can drive or catch a bus or train for the 20 or so miles south to Falmouth and enjoy a sheltered, sunny day on Carrick Roads. Other areas where this can work include Dyfed, the Lleyn Peninsula, south-west Ireland and some of the Scottish islands along with north Norfolk and Kent.

Winter breaks are a bit more of a problem. Perhaps the best course of action is to remove the weather from the equation altogether. Most of the major cities have some very interesting indoor attractions and there won't be the queues - this is also true for many worldwide destinations. However, if you can travel at short notice, check the weather and you'll be able to enjoy the sights and the culture. For example, with a mild south-westerly wind blowing, somewhere like Aberdeen is likely to get a good deal of shelter from the mountains of Scotland, the cloud breaks to their lee and some warm and sunny weather can be had. Similarly in a cold northerly air stream, Cardiff can be quite a good bet or visit one of England's south coast links courses for a good chance of enjoying a sunny weekend's golf.

Where will i find a winter wonderland? If you are going skiing or boarding, snow is obviously the priority. In the northern hemisphere February is high season, the days are starting to lengthen and the snow is usually good and plentiful. But what do you do if for whatever reason you can only travel at either end of the season?

One quite often hears the advice "go high". Yes it's true the snow will probably build up quickly and last longest on the higher-resort upper slopes. But these can be exposed and extreme wind chill can turn a day on these slopes into a matter of survival. The other problem is if the runs get a lot of sun. This can turn them slushy during the afternoons and after a cold night they can be very icy in the mornings.

The best idea is to try to choose one of the higher resorts that has a good range of station heights and has runs facing as many directions as possible. Areas that come to mind are Les Quatres Vallées and Jungfrau in Switzerland, Les Trois Vallées in France and the western Alps in Italy.

Mountain weather can change very quickly so it's a good idea to take a weather check before you head for the slopes. There is also evidence that global warming is having an effect on the number of avalanches in the Alps. Always make sure you know what the risk is and if you do ski off-piste make sure you've got a good guide.

The Rocky Mountains of North America are famous for their deep powder snow. This is due to the very cold, dry atmosphere at high altitudes, which encourages the snow to stay light and feathery without settling. In fact, Mount Rainier to the south of Seattle is one of the snowiest places on earth, recording over 30 metres - that's over 100 feet - of snow on average each year. The main ski areas, however, are to the north and to the south of this.

In the Canadian Rockies, both Lake Louise and Sunshine have top stations not far off 9,000ft. So do the resorts around Lake Tahoe on the Sierra Nevada in California and in Nevada. Across the border in Utah, the Salt Lake City ski area offers runs between 7,000ft and 11,000ft, as do the Colorado Rockies.

Has the holiday weather ever caught you out? My wife and I are keen walkers and a few years ago we planned to spend a couple of weeks in the Haute Pyrenees. We'd done lots of research and marked out routes on mountain maps. We arrived in southern France at the same time as an Atlantic low - we never actually saw the mountains as they remained in cloud for the entire fortnight. Fortunately our car was fitted with fog lights. Unfortunately we both went down with food poisoning too! The depression stayed with us all the way across France to give one of the roughest Channel crossings we'd ever experienced. To add insult to injury, it turned out to be one of our most expensive holidays ever - if you're spending lots of time in bathrooms we figured they might as well be nice ones and sped between swanky hotels in our dash back to the UK.

Where can i find out more? A great general reference book is The World Weather Guide published by Hutchinson. The World Meteorological Organisation, that's the UN agency that looks after weather, has a website with links to all the major weather services around the world - www.wmo.ch

The internet is a fantastic way of keeping abreast of the latest weather. Another good site giving an up-to-date summary on tropical storms is - www.solar.ifa.hawaii.edu/Tropical

If it's day-to-day weather details you're after or a longer-range forecast then the Met Office and BBC Weather Centre sites are reliable - www.metoffice.gov.uk and www.bbc.co.uk/weather. Television and radio are also good sources of information. During the northern hemisphere skiing season, BBC1 has a late-night forecast covering snow conditions and a weather outlook for the main winter sports areas once a week, and this year there is also an update during Ski Sunday. During the summer, that same late-night forecast concentrates on some of the main holiday destinations around the world.

For the USA, the Weather Channel site is excellent - www.weather.com

Winter sports fans will find the Ski Club of Great Britain site really useful - www.skiclub.co.uk

There are telephone information services providing all sorts of leisure forecasts and mobile phone networks are offering more and more of this sort of information, so check with your supplier.

If you're hooked on weather, here are a couple of holiday reads: Chasing The Monsoon by Alexander Frater (Penguin) - a fascinating account of his pursuit of the Indian summer monsoon from Trivandrum to Cherrapunji (one of the wettest places on earth); The Perfect Storm by Sebastian Junger (Fourth Estate) - this is the book the film is based on and the reason I gave up offshore yacht racing.