What is the chance of the UK experiencing a wetter than average winter?

 The current Three-Month Outlook covers the early winter period of November to January. It is not a daily weather forecast but instead focuses on the likely chance of the average temperature and rainfall amounts occurring during the three month period.

Our current Three-Month Outlook says that the period as a whole gives a 30% chance of being wetter than average and a 10% chance of being drier than average: leaving a 60% chance of the period being near average precipitation. Similarly, the current outlook indicates 45% chance of being milder than average and 10% chance of the period being colder than average and therefore a 45% chance of being average.

3 Month Outlook percentagesWithin the overall dominant weather type there will always be some variability. For example, a wetter than average winter will still include drier spells and a milder winter will always include cold spells. The Outlook gives no indication of where could see above average rainfall or heavier downpours and therefore when and where there will be impacts from rain.

Will Lang, Head of Civil Contingencies for the Met Office, said: “It is important to remember that the Three-Month Outlook does not attempt to provide a detailed forecast: instead, it gives the chance that the three-month period will be drier or wetter, warmer or cooler than average, as this information is useful to planners.

“The natural variation of our weather ensures that the day-to-day pattern will vary, and cold and wintry spells of weather occur even in mild winters. It is the overall pattern which is the important component of the Three-Month Outlook”.

The Three Month Outlook is based on output from a number of computer models, including the Met Office’s, which indicates the overall pressure pattern for our latitude to be consistent with a slightly positive phase of the North Atlantic Oscillation, which favours wetter and milder than average conditions.  La Niña, established in the tropical Pacific, also increases the chances of milder conditions later in the winter.

Long-range outlooks, such as the Met Office Three-Month Outlook are at the cutting edge of meteorological science, challenging the meteorological community the world over. While our understanding of the science behind atmospheric drivers, along with the technology to produce longer-range forecasts, is improving all the time, they are different to the highly accurate forecasts we are used to using on a daily basis.

The Outlook is produced for planners in government and business who make risk-based decisions. These users are aware of the uncertainties in this type of outlook and will include them in their decision-making process. Their skill or accuracy varies with the time of year and location, due to differences in the dependence of local weather conditions on global-scale atmospheric and oceanic processes. The UK is one of the most challenging regions for which to provide robust long-range information, as UK weather is dominated by the atmospheric circulation over the North Atlantic, which is highly variable.

The Outlook is updated and published monthly. It may change from month to month as the latest information with regard to the global drivers is assessed for their impact on the UK.

For a comprehensive forecast for your area check the 30-day and 7-day forecasts on the Met Office website, mobile app or following us on Twitter and Facebook. Keep track of current weather warnings on the weather warning page.

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