Weather sites have become increasingly sophisticated over the past couple of years. While they can't predict a Hurricane Ivan months in advance, they can help you choose the best month for a holiday, receive text updates, and predict sun, windchill and pollen levels in many parts of the world.

Best five-day forecast for the UK: metoffice.gov.uk/weather/europe/uk/.

Best four-week forecast for the UK: bbc.co.uk/weather/ukweather/monthly_outlook.shtml.

Best assessment of hurricane risks: intellicast.com/DrDewpoint/Library/1384/.

Best long-term world forecast: metoffice.gov.uk/weather/seasonal/.

Best guide to choosing a US beach: intellicast.com/BoatBeach/World/UnitedStates/ClimateGuides/. For an aerial survey, click on the 'Current weather' link from Intellicast.com.

Best SMS service: metoffice.gov.uk/services/mobile/tandp.html. Especially helpful if you are walking or climbing in a remote part of Britain where internet access is poor or non-existent. Texts cost 25p each.

Best for coastal forecasts and tide tables in Britain: bbc.co.uk/weather/coast/coastalforecast/.

Best averages for cities and countries: weather.com/activities/travel/vacationplanner/.

Best for forecasting the weather at big sporting events: bbc.co.uk/weather/sports/.

Best for European forecasts and sun and pollution indices: bbc.co.uk/weather/world/.

Best mountain forecasts in the UK: metoffice.gov.uk/loutdoor/mountainsafety/mountaincall.html. Forecasts for the Brecon Beacons and Snowdonia are free; for the Highlands and Lake District, however, the Met Office operates a premium rate phone line. Try scotmountain.co.uk/weather.htm for email updates on the northern Cairngorms, sais.gov.uk for avalanche forecasts, and the free regional updates at mwis.org.uk.