Winter so far – 18th February rainfall update

18 02 2014

As the UK heads into a period of more normal unsettled winter weather weather, the Met Office’s National Climate Information Centre has looked at statistics for this winter so far (from 1 December 2013 to 13 February 2014).

These add to previous facts and figures we put out earlier this month, and show a picture of continuing exceptional rainfall across many areas.

Looking at regions around the UK, these provisional figures show the region of central southern and southeast England has already exceeded its record winter rainfall in the series back to 1910. Rainfall here currently at 459.3mm*, 22mm above the previous record of 437.1mm set in 1915 with two weeks still to go to the end of the season. This winter also currently ranks as the 4th wettest winter (if there is no further rain) for southwest England and south Wales combined and the 3rd wettest for England South.

Both the UK as a whole and Wales are fairly close to exceeding their respective record wettest winter levels in the national series dating back to 1910 (see table below). Average rainfall for the rest of the month could see those records broken.

All countries across the UK have already exceeded their typical average rainfall for the whole winter (according to the 1981-2010 long-term averages). Normally at this stage of the season, you’d expect to have seen only around 80% of that whole season average.

All areas are also on target for a significantly wetter than average winter, with typically around 130-160% of normal rainfall if we get average rainfall for the rest of February.

All countries and areas are also on target for a warmer than average winter.

Current record wettest winters:

Country Year Rainfall Winter 2014 to date*
UK 1995 485.1mm 452.6mm
ENGLAND 1915 392.7mm 345.6mm
WALES 1995 684.1mm 645.1mm
SCOTLAND 1995 649.5mm 590.4mm
NORTHERN IRELAND 1994 489.7mm 386.2mm

*These are provisional figures from 1 December 2013 to 13 February 2014 and could change after final quality control checks on data.





A tale of two halves for February and winter

28 02 2012

As February and winter draw to a close, early statistics show that both have been stories of two halves.

We often talk about why you can’t pre-judge a month or a season at its half-way stage, and the latest figures perfectly illustrate why that’s the case.

The mean temperature for the first half of February was very low as cold weather gripped the UK – particularly in England where temperatures were 4 °C colder than the long term (1971-2000) average.

If you’d projected those figures out to the end of the month you would have expected one of the coldest Februarys on record.

However, the second half of the month (figures go up 26 February) has seen some exceptionally mild weather to balance things out and we have ended up with a rather average month for overall UK mean temperature which so far, was just 0.1 °C above average.

This story of two halves can be seen in the maps below, with the blue colours denoting lower than average temperatures in the half-month figures on the left, and the more balanced situation by the end of the month on the right.

Winter, which meteorologically speaking runs from December to February, has been a fairly similar story – but in reverse.

A mild December and first half of January meant we had a very mild first half of the season, which led to some media headlines mooting one of the mildest winters on record.

However, the last few days of January and the first half of February were colder than average, bringing the overall temperature for the season down.

With a couple of days still to go, the early statistics show the UK’s mean temperature for winter is 0.7 C above average, making this a mild winter – comparable with several other mild winters in the last decade.

One common theme between this February and winter as a whole is dry weather – particularly for the south and east of the UK.

February was particularly dry, with the UK having seen just 62% of the normal amount of rainfall we’d expect for the whole month by the 26th. With a few days left, this is unlikely to change by much.

England was the driest country, having so far seen just 43% of the rainfall we’d expect for the month and Wales not far behind at 49%.

Winter has also been dry overall in England, with just 82% of the rainfall expected for the season and Wales has seen 89%. This is slightly balanced out in the statistics by Scotland being wetter than normal over the season, seeing 116% of its normal rainfall.

The relative lack of rainfall for February and the season as a whole can be seen in the two maps below, with the brown colours denoting drier than average weather for the month on the left and for the season on the right.





Cold weather winning the war of probabilities

25 01 2012

Late last week we put out a blog article about an unusual amount of uncertainty in the longer range forecast (for the start of February onwards) for the UK.

This is because the atmosphere is currently in a finely balanced state and, depending on which way it goes, this could lead to a continuation of milder weather or a switch to much colder conditions – with frosts, ice and snow possible.

It comes down to whether we’ll continue to see the current pattern of westerly winds bringing in milder conditions from the Atlantic, or whether a high pressure system developing over Russia will extend towards the UK to bring in cold air on easterly winds.

The Met Office and forecast centres around the world have been studying this situation closely but the 50/50 split on which outcome is the most likely has persisted – until now.

It now looks as if the scenario for colder conditions is slightly more likely, but our forecasters stress that a lot of uncertainty remains and milder weather could return.

Looking at our current forecast for the end of next week, our guidance states: “…a general continuation of the cold weather type seems most likely, but it is by no means certain. There is a risk of snow, ice and sharp frosts, with easternmost parts being most prone. However we certainly cannot discount the possibility that mild west/southwesterly winds will return instead, bringing rain at times.”

Looking further ahead, the forecast for mid-February onwards remains very uncertain too. Looking at our current guidance, it states: “…the most likely outcome is for much colder weather with winds mainly from an easterly quadrant to prevail, bringing widespread frosts, and snow to some areas. In this scenario it would be the east that would be most vulnerable to snowfall. There remains an alternative scenario, in which milder westerly winds prevail, the chances of this alternative scenario are currently rated as about one in three.”

Our forecasters will continue to closely monitor the situation, so for the latest information check our weather forecasts and warnings about what to expect.








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