Mild wet winter continues in early January figures

16 01 2014

Provisional half-month statistics up to the 15th of January show a continuation of the generally mild and wet theme of the UK’s winter thus far.

The mean UK temperature up to the 15th of January is 5.1 °C, which is 1.5 °C above the long-term (1981-2010) average.

The mild January so far follows on from a mild UK December, which had a mean temperature of 5.7 °C, which is 1.8 °C above the long-term average – making it the eighth mildest December in records dating back to 1910, and the mildest since 1988.

It’s a similar story with UK rainfall. We’d normally expect about 48% of the January average rainfall by the 15th of the month, but the UK has seen 87.9mm so far – which equates to 72% of the January average.

As usual, there are regional varations. England has been particularly wet so far this month, having already seen close to its full-month average, and Wales is not too far behind. Scotland and Northern Ireland, however, are closer to the ‘normal’ amount of rain we’d expect at this stage.

The wet January so far once again follows the theme set in December, which saw 184.7mm of rain – which is 154% of the average for the month.

While this means January, and winter, so far have been mild and wet, it doesn’t mean they will finish that way. We often see half-month or half-season figures which then change dramatically by the end of the period. So the message is, it’s too early to judge how January 2014 or winter 2013/4 will finish up.

The main reason for the mild and wet weather so far is that we have seen a predominance of west and south-west winds, bringing in mild air from the Atlantic – as well as generally unsettled conditions.

The table below shows provisional figures from 1-15 of January, with actual figures so far compared to full-month averages. We would normally expect rainfall and sunshine to be about 48% of the full-month average at this stage.

Mean Temperature Sunshine hours Rainfall  
January 1-15
Actual Diff from Avg Actual % of Avg Actual % of Avg
  degC degC hours % mm %
UK 5.1 1.5 26.1 55 87.9 72
England 6.0 1.9 34.7 64 80.4 97
Wales 5.8 1.7 20.6 42 137.7 88
Scotland 3.6 1.0 15.4 43 91.2 51
N Ireland 4.4 0.2 14.6 33 62.8 54




October 2013 one of the top ten warmest

5 11 2013

Provisional Met Office statistics for October show it was one of the warmest in the national record dating back to 1910.

The mean temperature for the UK is 11.2 °C, which is 1.7 °C above the long-term (1981-2010) average. This makes it the 9th warmest on record, and means that five out of the top ten warmest Octobers have occurred since 2000 – the others being 2011 (11.3 °C), 2005 and 2006 (11.7 °C) and the warmest on record 2001 (12.2 °C).

Mild nights were a feature across the UK, with most stations south of Scotland yet to report an air frost.

Map showing October rainfall amounts relative to 1981-2010 average

Map showing October rainfall amounts relative to 1981-2010 average

October 2013 is also notable because it was, for most places, dull and relatively wet. Sunshine hours for the UK were 83 % of the long term average, while rainfall was 27 % above average. For England this was provisionally the wettest October since 2000 and equal-8th wettest in the series.

Northern Ireland and the Western Isles of Scotland have had around average sunshine, but Shetland, south-east Scotland and the north-west of both England and Wales have been particularly dull.

Mean temp Sunshine Rainfall
October 1-28 Actual (°C) Diff to Avg Actual (hrs) % of Avg Actual (mm) % of Avg
UK 11.2 1.7 77.2 83 161.1 127
England 12.2 1.9 87.3 85 139.1 152
Wales 11.9 2.0 77.6 83 223 131
Scotland 9.4 1.4 58 77 181 103
N Ireland 10.8 1.4 91.5 104 159.6 133

A full summary of the month will be available on our climate pages shortly





October set for top ten warmest

1 11 2013

5 November 2013 Update – The full month figures are available in our latest blog

Early statistics for October up to the 28th of the month suggest this October is likely to be one of the warmest in records dating back to 1910.

Map showing relative warmth of October temperatures across the UK.

Map showing relative warmth of October temperatures across the UK.

The mean temperature for the UK from the 1st to the 28th is 11.6 °C, which is 2.1 °C above the long-term (1981-2010) average. It’s currently ranked joint fifth warmest in the records, but this could change once the final three days of data have been included.

Mild temperatures were experienced across all parts of the UK – with October currently being in the top ten warmest for England, Wales, Scotland and Northern Ireland. However, it was particularly mild in Wales, with this October currently ranked as the joint warmest on record alongside 2001.

There were no autumn heat waves through October, just a persistence of mild conditions – particularly mild nights – and frost has been rare through the month.

October 2013 is also notable because it was dull and, for most places, relatively wet. Sunshine hours are currently below the long-term average, while rainfall is already above ‘normal’ levels for everywhere apart from Scotland – which is about average.

Below are figures from 1-28 October, and we’ll update on the full-month figures early next week.

Below is a table showing statistics for 1-28 October, and we’ll update with full-month statistics early next week.

Mean temp Sunshine Rainfall
October 1-28 Actual (°C) Diff to Avg Actual (hrs) % of Avg Actual (mm) % of Avg
UK 11.6 2.1 67.3 73 147.6 116
England 12.6 2.2 74.4 72 131.6 143
Wales 12.3 2.4 66.7 72 208.9 123
Scotland 9.7 1.8 52.7 70 157.9 90
N Ireland 11.2 1.8 84.1 96 145.6 122




UK’s unsettled weather and the jet stream

21 10 2013

The UK is set to see unsettled weather throughout this week as heavy rain and windy conditions are expected to affect many areas, whilst temperatures will remain mild for the time of year.

We talk about the jet stream quite a bit in the UK because it has such a big influence on our weather, and this week is no exception as it’s playing a leading role in determining the unsettled outlook.

What is the jet stream?

The jet stream is a band of fast moving westerly winds high up in the atmosphere which circle around the pole in the northern hemisphere. It can feature winds of up to 200 knots (230 mph) or more, and these winds tend to guide wet and windy weather systems which come in off the Atlantic.

The jet moves around a fair bit and its position can have a big impact on weather here in the UK depending on where it is.

If the Jet is over the UK or just to the south, we tend to get a lot of wet and windy conditions as it brings weather systems straight to us. If the jet is to the north of us, it guides that changeable weather away to the north to leave the UK with more settled conditions.

What’s the jet stream doing now?

Unsurprisingly given the outlook for this week, the jet is positioned more or less directly over the UK – but it’s the detail of its track which is important.

As you can see from the picture below, the jet currently swoops south from western Canada – moving over the Atlantic before taking a sharp turn north to head over the UK.

Forecast chart showing  expected position of the jet stream at 1pm on Tuesday 22 October

Forecast chart showing expected position of the jet stream at 1pm on Tuesday 22 October

This means relatively cool air is being dragged south then over the Atlantic, where warmer seas heat the air from below. This causes the air to warm and rise – creating instability and generating cloud and rain.

By the time weather systems reach they UK they have picked up a lot of rain and relatively warm air, bringing us the wet but mild conditions we are currently seeing.

What’s the weather outlook?

Currently unsettled weather looks set to impact the UK through the week, with heavy rain affecting many areas at times.

There may be more settled conditions on Thursday, and perhaps again on Saturday, but looking further ahead into the start of next week the outlook is for unsettled weather to continue.

You can stay up to date with what to expect with our detailed forecasts out to 5-days and our weather warnings, as well as a general view of what we expect out to 30 days.

You can find out more about the jet stream in our YouTube video.








Follow

Get every new post delivered to your Inbox.

Join 5,912 other followers

%d bloggers like this: