April 2016 summary

April is the middle month of meteorological spring, so as well as the traditional showers we might expect a steady increase in temperatures as the sun rises higher and the days grow longer. This year we got the showers, but temperatures actually fell as the month progressed and the last week of April was 1.4C cooler than the first. The average temperature for the month was 8.6C which is only a degree or so below normal, but a cold, dry polar airstream towards the end of the month made it feel colder than it was. We had colder Aprils in 2008, 2012 and 2013, but in those years April did at least finish up warmer than it started.

The rainfall total was 42.8mm which is right on the average – although it is often showery, April isn’t usually a particularly wet month. Despite occasional heavy showers there were no exceptional rainfall totals, and the wettest day was the 11th with 10.2mm.

Up to the 16th low pressure was in charge, with rain most days and a blustery spell around the 8th and a thunderstorm on the 14th. On the 16th a calm day with clear skies brought the highest temperature of the month at 17.9C, but even that was enough to spark off a heavy convective shower late in the afternoon.

Pressure began to build on the 16th, and from the 18th to the 21st whole the UK was under a large high pressure system. Although it was dry, there was high-level cloud which kept a lid on daytime temperatures but just allowed an air frost (-0.3C) early on the 17th.

The high moved away on the 21st, and for the next week we found ourselves between high pressure to our west and lows to our east. The result was a stream of cold, dry air fresh from the arctic keeping temperatures down and adding a noticeable chill factor. As this cold air met warm, moist air on its journey south, it generated some lively but very localised convective showers – April certianly lived up to its reputation in that respect – and on the 26th we were were treated to sleet in the morning (there was snow on the Brecon Beacons and Dartmoor) and a thunderstorm over the Bristol Channel during the afternoon. On the 28th it was cold enough for another overnight air frost.

Below-average temperatures in March and April mean that this spring is off to a cool start after our remarkably mild winter. Let’s hope May can put that right.

March 2016 summary

March was cool, wet and windy, although thanks to a spell of high pressure in the middle of the month it didn’t always feel that way. Total rainfall was 62.4mm which is on the high side for March but within the normal range. The average temperature was 6.6C, about a degree below normal, and there were six air frosts – more than we had in December 2015 or January 2016. In fact, March was colder than both December and January, and only 0.6C warmer than February. The highest temperature during the month was 14.2C on the 25th, the lowest March maximum we have recorded.

A spell of persistent high pressure, the first we have seen for some months, lasted from the 10th to the 21st and brought calm weather. There was some cloud, particularly towards the end of the period, but there were clear days too and when the sun shone it felt warmer than it was – helped by the lack of wind.

This quiet spell was sandwiched between two unsettled periods, with storm Jake early in the month and Katie on the 28th. Jake arrived on the 2nd as a secondary low pressure system which formed quickly over northern England while the “parent” low was north of Scotland. Squally weather here produced gusts to 40kts, but nothing out of the ordinary for March. Low pressure systems continued over the next week with some blustery convective showers, and on the 8th / 9th a low pressure system passing up the English Channel produced persistent overnight rain totalling 18.8mm.

After that soaking the high pressure arrived, and we saw no further rain until the 24th. The 25th saw a brief return to clear weather under a ridge of high pressure, but from the 26th the lows were in charge again. Storm Katie formed to the west of Ireland on the 27th and arrived here in the early hours of the 28th, passing right overhead shortly before 4am: before that time a South Easterly wind was gusting to 25kts, then there was a brief period of calm before a strong westerly wind signalled that the low was moving off east. A gust of 43kts was recorded at 0359, and the temperature dropped from 9.8C to 4C in the fresh polar air. Katie produced 16.2mm of rain.

As we came to the end of the month pressure began to rise again, bringing one final air frost early on the 31st.

February 2016 and winter summary

Coming after a couple of mild months dominated by a warm south-westerly airstream, February finally brought a bit more variety to the winter weather with gales, some spells of high pressure, and cold air from the north and east.

The month began with unsettled weather dominated by Atlantic lows, with gusts over 40kts on the 2nd and a long period of rain on the 6th which bought us a total of 27.8mm (but over 100mm down on Dartmoor). Things reached a climax on the morning the 8th, when a low pressure system crossing the south of the UK produced a gust of 50kts and an average wind speed of 33kts – both new records for this station.

The middle of the month saw quieter and brighter weather and a cold easterly wind, as a ridge of high pressure moved up from the south-west. The first air frost was recorded on the 11th, and the lowest temperature of the month was -3.4C early on the 16th.

The ridge dissipated over the following days and on the 21st a low pressure system north of Scotland drew in very warm air over the south of the UK, while the north shivered in a polar airstream behind the cold front. The temperature here reached 15.3C during the afternoon of the 21st, equalling a record set in February 2012. It wasn’t to last, though, and the as the cold front made its way southwards we were soon in the polar air too, with clear skies and overnight frosts.

The last week of February was dominated by high pressure over the south of the UK and a dry north-easterly breeze, which made it feel colder than it was.

The rainfall total for February was a modest 57mm. It wasn’t particularly cold overall – the average of 6.0C was actually a little above normal – but there were nine air frosts during the month compared with only three in January and none at all in December. It was a windy month, thanks mostly to the gales during the first week or so, and a wind run of 3520nm makes it our second-windiest February – beaten only by the storms of February 2014.

The extraordinarily mild December and a mild January combined to make this the warmest winter we have recorded here, with an average temperature of 8.1C – the next warmest was 2013/14 which averaged 6.8C, so the gap is large. This has also been our windiest winter, with a total wind run of 9,698 nautical miles – the previous record was 9,579NM in 2011/12, and 2013/4 which is remembered for the St Valentine’s Day storm managed only 9,010NM. The winter’s rainfall total was an unexceptional 186.4mm.

Warmest February day

Today’s daytime (0600-1800) average temperature was 12.6C making this the warmest February day since the station opened in 2007, and beating the previous record of 12.4C set in 2011. The maximum temperature recorded today was 15.3C, which equals a record set in February 2012.

Despite today’s exceptional mildness, this February is currently in third place for the overall average temperature – 2014 and 2011 were both warmer – and with some cold air on its way to us for the coming week that situation is unlikely to change. We can be pretty sure, though, that this will turn out to be our mildest winter on record thanks to the exceptionally mild December and January.

New wind speed records today

We have had plenty of warnings that low-pressure system Irene would bring notable gales, and we have just seen a new gust speed record for this station – 49.6 kts (57mph) was recorded at 1115 today. The previous record of 46.1 kts was set during that very stormy spell almost exactly two years ago when the railway in South Devon was washed away.

Lets hope there is no repeat of damage on that scale, but at the time of writing (1130) wind speeds are still increasing – the average is currently 34kts, which is also a new record for this station. The MetO forecast is that the peak will be around lunchtime today, so we may see even higher values before things quieten down.

Wind gust closes weather station!

Apologies for the break in service late this afternoon. As local residents will know, the power went off here at about 1515 and didn’t come back for a little over two hours. The computer can run for a while without mains electricity, but closed down at 1715 when the battery power ran out. Hence the web site updates stopped until power was restored and the system rebooted. I then did a check to make sure we had lost no data – all is well.

We know the power cut was caused by damage to overhead lines in the village, and it may well be associated with a wind gust of 41kts which occurred at 1515 – exactly the time the power went off. The gust was associated with a squally shower which only produced 0.2mm of rain, but also caused a sharp drop in temperature and, as we saw, packed quite a punch in the wind department as well. There are quite a few squally showers on the radar at the moment, but we can do without any more like that one – at least until the batteries here have recharged!

January 2016 summary

Ah, well – it looked for a couple of days as if January was going to bring us some proper Winter weather, but Atlantic low pressure systems dominated and it was another month that was more notable for warmth than cold – though not quite so extreme as December.

The first week or so of January saw a continuation of that warm and humid airstream which characterised most of December, so that daytime temperatures were generally into double figures. A succession of Atlantic lows meant that it rained most days and there were a few blustery winds. During the second week things became a little cooler as the lows began to draw in polar air, and a short-lived ridge of high pressure brought clear skies and our first air frost since November early on the 16th with a minimum of -1.4C.

Temperatures dropped again on the 19th and 20th when a slack area of high pressure formed over the south of the UK, with a minimum of -5.9C recorded early on the 20th: but the following day saw the return of the mild South Atlantic airstream and temperatures were soon back into double figures, with a maximum of 14.7C on the 24th.

The average temperature for the month was 6.8C, a degree or so above normal and our warmest January since 2008. Rainfall came to 66.4mm which is nothing exceptional, and although there were some blustery days it was not an unusually windy month.

With a mild January and the exceptionally mild December, it will be no surprise the average temperature so far this winter is well above normal at 9.0C – that’s about 3.5C higher than we would expect at this point. The warmest winter we have recorded here so far was 2013/14 which averaged 6.8C, so unless something remarkable happens during February that record looks set to be broken.

Winter has finally arrived

Winter finally seems to have arrived following our extraordinarily mild December, with the thermometer dropping to -5.9C at 0351 today. That isn’t an exceptional figure for mid-winter, but we do have to go back a bit to find a lower one – to 4 February 2012 to be precise, when we recorded -6.9C. Our record low is -11.3C back in December 2010, and last night’s temperature was our 18th-lowest since the station was set up in 2007, so it’s a long way off being a record-breaker. Last night’s average temperature (1800-0600) was -3.4C, our 11th= coldest night, so no prizes there either. Still, after all the mildness of recent months it certainly feels cold, and it’s good to see some clear skies again.

The average temperature so far this January is 5.6C which is what we would expect at this time of year, and 52.6mm of rain so far is  about right too. After all the anomalous weather we saw at the end of 2015, things seem to have got back to normal.

Barometer errors

The barometer on the weather station is behaving erratically – from time to time it is under-reading by up to 3 hPa, then returning to the correct value. A replacement part has been ordered, but in the meantime if the pressure figure on the web site looks wrong then it probably is. Apologies for the problem.

Update 15 January 2016 – the barometer problem should now be fixed.

December and full year summary

December was one of the most extraordinary months we have recorded here, and not always for good reasons. The outstanding feature here was the mildness, but for many in the north of the UK it will be remembered for the rainfall that led to catastrophic flooding.

Our December rainfall total was 63mm. Many places further north recorded much more than that in a day – maybe on several days – but there was no exceptional rainfall here: it rained on 25 days during the month, and the highest daily total was 15.8mm on the 30th.

Although we didn’t get the extreme rainfall, we did feel some effects of the procession of low pressure systems that caused so much damage further north. It was a windy month, our second-windiest December since the station was set up in 2007 and our sixth-windiest month overall. As storm Frank was bringing havoc to Northern Ireland and Scotland on the 30th, high winds caused the collapse of the derelict pier at Birnbeck Island not far from here: but the highest windspeeds were felt during a squally shower on the 31st with a gust of 33.9kts.

December’s average temperature was 11.2C, by far the warmest we have recorded (December 2011 was next warmest with 7.6C), 0.2C warmer than the previous month (which was the warmest November we have recorded), and a full 6C above normal for the time of year. The maximum temperature was 15.4C on the 20th, also a new December record, and the warmest day (0600-1800) was Christmas day with an average of 14.2C – which was equalled by Christmas night (1800-0600), also averaging 14.2C. These are figures we would expect to see in May or June.

Like November, it was an overwhelmingly dull month with a persistent warm and humid south-westerly airstream – there were only a couple of clear spells, and one of these brought the lowest overnight temperature of 2.3C early on the 9th. There was no air frost – the thermometer never dropped to freezing, another first for December at this station.

We arrived at the end of 2015 with the grass still growing – our second-warmest year on record with an average of 11.2C, a figure beaten only by last year which averaged 11.6C. The highest temperature recorded during 2015 was 29.7C on 1st July, and the lowest was -3.4C on 23rd January (we had frosts then – remember them?). The rainfall total for the year was 785mm, close to our average yearly figure. Overall, this has been an uninspiring year with a particularly lacklustre summer and few redeeming features. Here’s to 2016!

More December temperature records

As the north of England struggles with prolonged rainfall and catastrophic flooding, down here the December temperature records just keep on falling. Yesterday saw a new record daytime (0600-1800) average of 14.2C: and, if that wasn’t enough, Christmas night (1800/25th to 0600/26th) saw exactly the same average, beating the overnight record set only a few days ago.

The average so far this December is now 11.3C, about 6C above what we would expect for December and still warmer than the record-breaking November.

As I’m typing this I see the thermometer is at 14.5C and rising. I wonder if we might see a new maximum temperature too – the current record is 15.4C early on the 20th. Watch this space.*

(*) Update 1900 – no new maximum temperature record today, but we came close with 15.3C at 1355. More exceptionally mild weather is forecast before the end of the month, though, so it could still happen.

And warmer still . . .

Yesterday’s record December temperature of 15.1C has been beaten already – just after midnight, thanks to warm air streaming up from the southwest, the thermometer here reached a new December high of 15.4C.

The average overnight temperature (1800-0600) hit 13.9C again, despite some clear spells, and this month’s average temperature now stands at 11.5C: warmer than November, and approaching October’s average of 11.8C.

Warmest December night

There has been some talk in the media today about the exceptional warmth last night, and the figures for this weather station are no exception – last night’s average for 1800-0600 was 13.9C, by far the warmest December night we have recorded since the station was set up in 2007. To underline how very mild this December has been, seven of the top 10 warmest December days and nights recorded here have occurred during this month.

The average temperature so far this month is now 11.4C: that’s an increase of 0.3C on the average up to three days ago, and 0.4C warmer than the average for the whole of last month (which was our warmest November on record). A normal figure for this point in December would be 5.1C, and the previous record-holder for the same period was 2013 with 7.4C – so this December so far is 4C warmer than 2013, and the gap is widening.

One other point – at 0736 today we recorded a temperature of 15.1C, a new record high for December.

Needless to say there have been no air frosts this month, and from the forecasts it looks as if we could be heading for a frost-free December. Meanwhile, the hedge is still growing . . .

 

 

 

 

Record-breaking December mildness

The mild weather that we experienced in November is still with us, and the mean temperature so far this month is 11.1C.
This station’s average for the first half of December in previous years is 5.2C, ranging from 1.3C for the first half of
Decemer 2010 to 7.5C in 2013. The current extraordinarily mild spell follows the warmest November we have recorded since the station was set up in 2007.

At this point in December we would normally have seen several air frosts: on average the thermometer here has dipped below zero on five or six occasions by the 16th. There had been 11 air frosts at this point in December 2010, but only one in 2011. In the first half of December this year the lowest temperature we have seen is 2.3C – there have been no air frosts at all.

As with November, the cause of this mildness is a persistent air flow from the south Atlantic: a conveyer belt of warm, wet air. Satellite images taken during the devastating rainfall in Cumbria from the low pressure system “Desmond” showed a line of cloud stretching right back to the Bahamas, and as this warm, humid air rose over the Lake District Fells it deposited rain for hour after hour. The rainfall total here so far this month is a modest 18.6mm, and apart from the unseasonal temperatures the main effect of the air stream has been a blanket of cloud – it has been unrelentingly dull and gloomy.

Forecasters are predicting even milder weather for the coming few days so we may see that December temperature average climb higher still. Gardeners will know that we need hard frosts in the winter to kill the pests and allow plants to become dormant and get some rest: I can tell you that the hedges and grass here are still growing.

November 2015 summary

November was unusually mild and windy, but not particularly wet. Low pressure systems were the dominant feature, but for much of the month there was a persistent high pressure area over Europe and, as the Atlantic lows moved along the northern edge of this high pressure, warm and humid air was channelled over the south of the UK – hence we saw a good deal of mild and cloudy weather.

November began with very quiet weather – almost a dead calm – and for the first couple of days low ground was covered in a blanket of fog while hilltops were bathed in sunshine. A temperature of 22.3C was recorded at Trawsgoed in Wales on the 1st, a new UK record for November, but here in the fog we could only manage 12.2C. The 6th produced a new November temperature record for this station, reaching 17.7C at lunchtime in cloudy conditions – a good indicator of the warmth of the south-westerly airstream. The arrival of the first low pressure system to be named by the Met Office, Abigail, on 12th November put an end to the quiet spell, and was soon followed by Barney which produced the highest wind speeds of the month – an average of 27kts gusting to 36kts was recorded on the evening of the 17th.

The only chilly spell was from the 20th-24th, when the high over Europe receded and Atlantic lows pulled cold Polar air over the UK, producing the only air frost of the month early on the 23rd. At least we saw some blue skies in the cold, clear air.

The end of the month saw another area of high pressure develop to our south and a deep low pressure system (Clodagh) to the north. This meant a return to milder weather, but also brought more wind and rain – alhough wind speeds were not quite as high as they were in the middle of the month, the wind was persistent. Overall, this was the second-windiest November recorded here.

It was also the warmest November we have recorded with an average of 11C, as well as that high of 17.7C. The rainfall total of 67.4mm, though, was a little below average.

Despite the mild November, overall autumn temperatures were about average at 12C – September and October were both fairly cool months and offset the mild November. Rainfall was below average, though not exceptional, at 150.6mm.

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Updated 2 Dec 2015 to correct the date of the record high temperature of 17.7C.