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How cookies are used by the Met Office

You are asked to set your cookie preferences when you first visit the website on a new device or browser. You can change your preferences at any time.

Review or update your cookie preferences

Restricting cookies may impact functionality on the website. For example, your recently searched places will not be saved if you reject ‘Store and/or access information on a device’.

How we use cookies


When we provide services, we want to make them easy, useful and reliable. Where services are delivered on the internet, this sometimes involves placing small amounts of information on your device, for example, computer or mobile phone. These include small files known as 'cookies' or 'web storage'. 

These pieces of information are used to improve services for you by:

  • enabling a service to recognise your device so you don't have to give the same information several times during one task
  • recognising that you may already have given a username and password so you don't need to do it for every web page requested
  • measuring how many people are using services, so they can be made easier to use and there's enough capacity to ensure they are fast
  • making advertising more interesting, by collecting statistical and behavioural data to ensure the adverts that you see are more relevant to you
  • allowing you to share content on social media sites such as YouTube and Twitter.

You can turn cookies off, however, due to their role of enhancing or enabling usability and site processes, disabling cookies may prevent you from being able to use certain parts of this website.

If you would like to disable cookies on your machine, you can do this through your browser settings. The 'Help' function within your browser will tell you how.

First-party cookies

Personalising the weather forecast and observations pages

See Web storage.

Cookies consent

Name Purpose Expires
CookieControl, CookieControlTC and CookieControlAC Cookie Control cookies. This cookie is set to remember the user’s cookie preferences. The preferences are available to third parties who need consent to place cookies.

365 days


The Met Office uses Google Analytics to understand how people are using the website and identify areas that can be improved or removed. The Google Analytics cookies are used to produce statistics on how the site is used. These cookies therefore allow us to recognise and count the number of visitors and to see how visitors move around the site when they're using it. This helps us to improve the way our website works, for example by making sure users are finding what they need easily. These services are provided in Europe by Google Ireland Limited and elsewhere (outside the EEA and UK) by Google and affiliated Google Entities.

Example cookie names:

  • starts with _ga
  • _gid
  • starts with __utm

See Google Analytics Cookie Usage on Websites for more detail.

Test improvements to the website

Google Optimize is sometimes used to test small changes to the website to see how well they perform. This is known as A/B testing.

Example cookie names:

  • _gaexp
  • starts with _opt_

See Google Optimize Cookie usage for more information.

We also sometimes perform A/B testing using our own tools instead of Google Optimize.  In this case alternative cookies will be used.

Example cookie names:

  • abTestVariant


Helps protect the site from large amounts of traffic.

Example cookie names:

  • starts with _cf
  • starts with cf

See Understanding the Cloudflare Cookies for more detail.

Site feedback cookies

The Met Office uses these cookies to choose which survey to show you based on the page you are visiting.  This helps us to measure how different parts of the site are being received by the people who use them.

Example cookie names:

  • mo-gsc-state

  • mo-gsc-widget

Help diagnose problems

If you are having problems with the Met Office website we may send you a link to a page that will test your browser's capabilities. One of these tests is to see if your browser will accept cookies.

Name Purpose Expires
testcookie test if your browser is accepting cookies when user exits browser

Ensure your session is consistent

Stores which web-server you have connected to in order to provide a consistent session.

Name Purpose Expires
weare in order to provide a consistent session when user exits browser
SERVERID in order to provide a consistent session less than 1 hour

Searching the website

Set when you use the Met Office search feature.

Name Purpose Expires
JSESSIONID in order to provide a consistent session when user exits browser
__KBLoggedIn__ 0 or 1 deleted

Premium services

Our commercial services use cookies to manage which services you have access to, ensure a consistent session and to manage the sign in process.

Name Purpose Expires
AMAuthCookie Allows users who've logged in to access Premium resources when user exits browser
amlbcookie Allows the user's session to be pinned to a single server when user exits browser
WT_FPC Cookie set by WebTrends analytic service 10 Years
authpath Allows Akamai to ensure user has access to correct paths when user exits browser
DProPCookie Stores information needed to re-create a session 25 Days
hist_nsdyt Stores the list of services for display 30 Days
iPlanetDirectoryPro Facilitates Single Sign On when user exits browser
Meto-LocationGroup Contains user's location groups when user exits browser
Meto-Subscription Contains user's subscriptions when user exits browser
Meto-UserAccount Contains username, user ID and organisation ID when user exits browser

For more information on commercial service cookies, please refer to the details of the service or contact us at [email protected].


Many of these are used on older parts of the website and are being phased out.

Name Purpose Expires
III_SESSION_ID in order to provide a consistent session when user exits browser
SESSION_SCOPE in order to provide a consistent session when user exits browser
PHPSESSID in order to provide a consistent session 4 hours 46 minutes
TWIKISID in order to provide a consistent session when user exits browser
fontsize your preferred font size e.g. large < 24 hours
style if you have enabled high contrast view < 24 hours

Third-party cookies

Embedded media and other external sources of cookies

When a video or Twitter feed is embedded in one of our web pages it may set third-party cookies.


  • YouTube.com
  • Twitter.com
  • Instagram.com

Advertising cookies

Adverts are served on the website. If you have consented, Interactive Advertising Bureau (IAB) registered advertising vendors may set third-party cookies. You can review these vendors and their privacy policies at any time. Adverts may come from many different vendors including Google Advertising. More information can be found on the types of cookies used by Google.

Web storage (localStorage and sessionStorage)

Similar to cookies but the data is stored in your browser only and not sent over the internet. LocalStorage data does not expire. SessionStorage data expires when you close the browser window.


User preferences

Name Purpose
MoWxPreferredLocation, moPreferredLocation user's preferred forecast location
MoLocationSearchHistory, MOWxDomesticLocationHistory user's location search history
metoffice_expandedforecasttable, MoreDetail user's preferences for More Detail view
MOWxPrefs preferences for map-based pages
moWeatherUnits, MOWxUnits user's preference of units e.g. Celsius or Fahrenheit
MOWxWidgetPreferences user's selected widgets to be displayed on the home page set via the Customise button

Published June 2018

Updated April 2023