Frequently asked questions

Access keys are keyboard shortcuts which allow a user to navigate a web site without using a mouse or other pointing device. This can sometimes be quicker and may assist those with motor skill difficulties.
How to use access keys on this web site

Firstly, ensure you are looking at the latest picture by pressing Ctrl and Reload/refresh. The graphic/text will be updated when there is a significant change in the forecast. The weather symbols are valid for the time shown above the map. The associated text should always be read as this will expand and amplify the graphic.

You need to ensure that JavaScript is switched on.

How to do this in Internet Explorer:

1. From the Tools menu select Internet Options.
2. From the Security tab set the security level to Medium. JavaScript will automatically be enabled.
3. If you wish to have more control over your security settings, select the Custom security level and click on Settings. Scroll down to the bottom of the settings window and ensure that Active scripting is enabled.

How to do this in Opera:

1. From the Tools menu select Quick preferences and make sure Enable JavaScript is ticked.

How to do this in Firefox:

1. From the Tools menu select Options.
2. From the Content tab make sure the Enable JavaScript checkbox is ticked.

How to do this in Safari:

1. From the Safari menu select Preferences.
2. From the Security tab make sure the Enable JavaScript checkbox is ticked.

You will need to look at your browser's help to see how to do this on other browsers.

You need to ensure that JavaScript is switched on. See the answer to Q1.3 for how to do this.

See our Accessibility page for instructions on how to make text larger in your browser.

This is caused by some phone software pacakges (e,g, Skype) replacing numeric strings , which resemble phone numbers, with a phone number and country code flag. You will have to look in your software package or use Google to find out how to disable this.

You need to refresh your page. We have extensive checks to ensure that data is updated on time. You might find the problem is at your ISP, contact them to ask for their pages to be updated. See question 1.11 on how to clear your cache.

If you receive a datafeed from the Met Office, we will place a link to you on our links page. For information on how to receive a datafeed, please email the Customer Centre.

You need to enable cookies to use the registered services. Our policy about cookies can be found on our privacy page.

To enable cookies in Firefox 3

1. Go to Tools Options
2. Click on Privacy tab
3. Either click 'Accept cookies from sites' or click Exceptions button and add our site to the list

To enable cookies in Internet Explorer 7

1. Go to Tools/internet options
2. Click on the Privacy tab.
3. Click on advanced
4. Select 'Override automatic cookie handling'
5. Click Accept (or prompt) First Party cookies

To enable cookies in Internet Explorer 6

1. Go to Tools/internet options
2. Click on the Privacy tab.
3. Move the slider to a suitable setting

You will need to look at your browser's help to see how to do this on other browsers.

Note that firewalls such as ZoneAlarm may have settings that may have to be changed to allow cookies.

You need to enable cookies to use the registered services. Our policy about cookies can be found on our privacy page. See the answer to question 1.9 for instructions about enabling cookies.

See wikiHow about clearing cache in various browsers

The Met Office is not responsible for the content of external internet sites

See our Services page.

As a result of aviation customer feedback we don't intend to provide TAFs and METARs on WAP at this time, but will keep this under review.

A weather information guide is available.

A weather warnings guide is available. Also see Advice on actions to take when severe weather is forecast.

A weather gadgets guide is available.

A RSS feeds guide is available.

A Marine forecast guide is available.

The Met Office website has not been specifically designed to enable downloads to mobile devices. Various mobile devices use different browsers and have different levels of javascript support. This means that the appearance and functionality of our website experienced on your mobile device may not be the same as experienced on your home computer.

Click the link below to restore the defaults to London(Heathrow)and UK
Restore the homepage defaults  

“My bookmarks” is a feature that allows you to create your own, customisable, quick links menu.
You can store up to 30 quick links by clicking on Add... featured at the top of each page.
To remove a link, simply visit the relevant page and click Remove...

Cookies are used to save your settings for features such as the “Customise my weather”, “My bookmarks” and page display options on our website. If you have specifically chosen to clear Cookies when you exit your browser, these settings will be lost.

Note the answer Q1.2. The text is updated at 0600, 1200 and 1800.

Get the latest forecast or observations from the Met Office. The past weather pages also give a brief overview of the climate of various regions round the world.

However, if you want detailed climate values for a specific place try World Climate. You can enter a location when prompted and this then provides long-term average values for daily maximum and overnight minimum temperatures, also rainfall, on a monthly basis. Remember that these are averages and that there can be significant variations from these figures.

You can see the decode by clicking on the 'Key' link on the pages with the weather symbols.

The wind chill or wind chill factor is the apparent temperature felt by warm blooded creatures — primarily humans — during cold and windy conditions. However, many factors contribute to the degree of discomfort experienced by human beings, including cold windy conditions, insulation, humidity, the quality and amount of clothing worn, body temperature, physical fitness, metabolic rate and psychological condition of the subject.

Jet streams are ribbons of very strong winds which move weather systems around the globe. They are found 9–16 km above the surface of the Earth, just below the tropopause. The position of a jet stream varies within the natural fluctuations of the environment. They are caused by the temperature difference between tropical air masses and polar air masses (PDF, 863 kB). What happens in one part of the world depends on what is happening elsewhere — the atmosphere is a complete environment with numerous connections.

Visit our Climate Change Centre or read our climate change Frequently Asked Questions page.

The Celsius scale is the World Meteorological Organization standard for temperature measurement and is used throughout the world by the meteorological community for global exchange of information.

From Celsius to Fahrenheit - F = C × 9/5 + 32

From Fahrenheit to Celsius - C = (F − 32) × 5/9

where C is the value in Celsius and F is the value in Fahrenheit.

Multiply the millibar value by 0.02953 to get the value in inches.

The SI unit for pressure is a pascal. The worldwide meteorological community uses the hectopascal, i.e. a hundred pascals, which is the metric equivalent of a millibar. However, millibars (and inches) are still used in some public forecasts in the UK and USA.

UTC stands for Universal Time Coordinated and it is equivalent to GMT. The Royal Observatory web site has more information on the history of timekeeping. It also has a description of local time.

Many questions about hurricanes are answered on our Tropical Cyclones page.

Atmospheric pressure varies over time and space and also varies with height. Since the altitude of the barometer normally stays constant (the station height) a correction is made to the reading to make it equivalent to the mean sea-level reading. This is done so that readings from different locations can be compared, with differences due to height being removed. Aneroid barometers are normally adjusted to mean sea-level values — read the barometer's instructions to see how to adjust the instrument (normally by a screw on the back). Mercury barometers cannot be adjusted (don't tamper with them because a mercury spillage is a health hazard).

To get the value for your barometer, choose a high-pressure day, pressure values are not changing very much - you can watch the TV forecasts for such a day. Go to the Met Office's observation page and choose the station nearest to your location - on a quiet weather day the distance away from you will not be significant. Adjust the barometer to the station's pressure value. You can check your barometer on other days but will have to compensate for fast-changing pressures or distance if the pressure is low or changing fast. The observation includes information about how the pressure is changing.

For many a white Christmas means a complete covering of snow, ideally falling between midnight and midday on the 25th.

However, the definition used most widely, notably by those placing and taking bets, is for a single snow flake (perhaps amongst a shower of rain and snow mixed) to be observed falling in the 24 hours of 25 December.