UK Weather - Autumn 2018

[Simon Culling]

Meteorological Autumn began on the 1st of September and much of the eastern half of the UK enjoyed a warm and sunny day after a cool start. The temperature reached 25.2*C at Hull (East Park) and 25.1*C at RAF Linton-on-Ouse and was close to this level in many parts. The west was more cloudy with a few bits and pieces of rain. Here in Hythe it was a glorious sunny day with a maximum of 22*C after a cool and misty start to the day with an overnight low of 10*C.

The models were predicting a warm and dry first half of September a few days ago but have drifted somewhat in the last day or so to a cooler regime from the second week, although the generally dry theme remains. We have got used to warm and settled autumns in recent years with a delay in the usual onslaught of weather systems off the Atlantic, and there are some suggestions that the decline in Arctic sea ice has been one of the causes of this shift towards more northern blocking. Time will tell. Here is a link to one of the papers that started the discussion + research:

https://agupubs.onlinelibrary.wiley.com ... 12GL051000

[Simon Culling]

We had two sunny days this weekend here in Hythe - something I have seen called a 'blue dome day' on this site. This would have been a very good description of Sunday when the sky was completely clear and we reached 23*C - further inland 25/26*C was recorded. The two photos below give an idea of how beautiful the day was. The first was taken from the top of Mullens Lane (between Hythe and Dibden Purlieu) and the second from the shore of the Solent estuary looking towards Southampton Docks. The large liner with the red funnel is the Queen Mary 2, the flagship of the Cunard Line.

The forecast has changed again with a 'cut-off' low expected to form to our NW and drift south over the UK into the coming weekend. Not only will we see some rain, but it will become a lot cooler.

[Orion]

Sounds like a perfect day
All the trees very green still, and what a massive ship!

[Simon Culling]

Orion, the trees around here are surprisingly green despite the long period of dry weather earlier in the summer. In some locations the trees have not fared so well and have seen some of their leafage turn brown prematurely, but the general colour change for autumn is still a month or so away. The recent rainfall in the last couple of weeks has certainly helped the grass which has now mostly recovered with green new-growth appearing.

It has remained mostly sunny here in Hythe for the last few days with the mercury in the low twenties by mid afternoon. The CET for September was 16.7*C (+2.0*C) up to the 4th, which is ahead of August. The EWR was just 3mm up to the 4th, which is 4% of the monthly average of 78mm.

There remains quite a lot of uncertainty regarding the low pressure system due this weekend, with the current forecasts backing off from much rain here in the south. After that, it looks like a return to warmer and sunnier weather again for us southern softies.

[Simon Culling]

We remained dry here in Hythe yesterday (Sat 8th Aug) as the main rain area moved eastwards across central parts of England and Wales, but there was a lot of cloud and only hazy sunshine at times. It has been a little cooler in recent days (particularly at night), but still only around the average - it is one of those spells of weather where not much of interest is happening. Cloudy start to Sunday (Sc), but this has now broken up (early afternoon) to scattered Cu and plenty of sunshine.

Looking forward for the coming week and not much happening is the general theme. It looks to remain dry here in the south with some warmer air arriving form the beginning of the week, but all very average.

[Simon Culling]

The NW/SE split in the weather has remained in place over the UK for the last few days with rain and wind in the NW half and dry and brighter weather in the SE. The mild and muggy air has remained in place over the SE with the temperature reaching 25.3*C at Exeter Airport and 25.2*C at London Heathrow yesterday (Tues 11th Sept). However, the cold front is now into the south this morning (Weds 12th) and the much cooler and fresher air will be here for a few days. It is highly likely that today will see the first day not to see a temperature of 20*C recorded somewhere in the UK since mid-May.

Whilst understandably all the attention is on Hurricane Florence, one of the other storms (Hurricane Helene), which is currently in the mid-Atlantic, is re-curving NE and the current track directs it towards the UK for the middle of next week. In these circumstances all of the models begin to struggle, and we have a huge range of forecasts as a result. The most likely scenario is that the feature (then an extratropical depression) will move close to the west of the UK and this will draw in very warm air over the SE - could see close to 30*C in this area. However, a lot will change in the forecasts in the next few days.

[Simon Culling]

Expectations from former Hurricane Helene have been downgraded somewhat in the last day or so as it appears the system will be filling slowly as it crosses Eire on Mon/Tues this week. The Met Office have a weather (wind) warning for counties bordering the Irish Sea, but Met Eireann only have a rain warning for the NW of the country. It was a warm day for the time of year today (Sunday 16th Sept) with the temperature hitting 24*C in London and East Anglia and tomorrow will be a degree or two warmer as the approaching tropical based system advects plenty of warm air northwards over the UK from the south. After that, the Atlantic looks to liven up a bit and a succession of systems look set to move towards the UK, although the SE half will miss most of the wind and rain. It will turn quite a bit cooler by the end of the week, particularly by day.

The CET for September was 14.6*C (+0.4*C) up to the 15th and the EWR was 20mm up to the 14th which is 26% of the monthly total. Yet again, most of this rain has been in the north + west.

[Simon Culling]

The depression (containing the remnants of ex Hurricane Helene) passed up the Celtic Sea today as a filling feature and mostly passed by unnoticed. The UK had a breezy day, but most areas saw a few gusts to around 40mph and most of the SE half remained dry although rather cloudy. Even exposed sites on the Irish Sea only saw gusts to 60mph. The warm air was drawn north over us yesterday and the temperature hit 25-26*C in eastern parts with plenty of warm sunshine which extended far enough westwards for Hythe to have a lovely sunny day. Today, despite the cloud, the mercury still hit 23*C.

As if to make up for this, the jet stream across the Atlantic has rapidly increased in speed behind this tropical intrusion and a deep depression will form and run across southern Scotland tomorrow (Weds 19th) bringing strong gales to the north of the UK - gusts to 80mph have now been forecast from what has been named Storm Ali, the first of the season. This will herald the start of a very disturbed spell of weather into the weekend with some of the wind and rain extending further south as times go by. It will also turn a little cooler.

[Simon Culling]

Storm Ali moved very quickly across the north of Ireland and across northern Scotland (at roughly 975mb) to be over the Northern Isles (Shetland) at 969mb by 6pm this evening, Wednesday 19th September. It brought a swathe of strong winds to the north of the UK, but centred on the northern and western Ireland and through central Scotland, and particularly the Clyde and Forth valleys. This storm did not really feature in the forecast 2-3 days ago and shows that the atmosphere can still surprise us. The strongest wind gusts I can find are:

91mph at Mace Head (Co Galway) + Killowen (Co Down)
83mph at Eglinton Airport (Derry City)
81mph at Orlock Head (Co Down)
78mph at Dundrennan (Dumfries + Galloway)
77mph at Drumalbin (Lanarkshire), Newport Furnace (Co Mayo), Inverbervie (Aberdeenshire) Salsburgh (Lanarkshire) + Capel Curig (N Wales)
75mph at Claremorris (Co Mayo), Loch Glascarnoch, Aberdaron (N Wales) + Charterhall (Scottish Borders)
72mph at Glasgow Airport + Loftus (Northumberland)

Some higher gusts were recorded, but not at a standard height, including 102mph on the Tay Road Bridge in central Scotland. Tragically, there have been a number of fatalities.

https://www.bbc.co.uk/news/uk-45572946

Looking ahead, we have a very unsettled spell coming up, with an area of heavy rain developing over Wales and the Midlands (50-100mm) tomorrow with another deep low sweeping this away by Friday morning - with quite a sharp cold front expected giving squalls and heavy rain. A frontal wave arriving Sunday will contain some of the remnants of Hurricane Florence and the models are struggling with this feature and are forecasting anything between a bit of wind and rain to a dartboard of a low over the middle of the UK. The latter may be a bit OTT.

EDIT: It was also very wet in western Scotland on Wednesday as storm Ali had a lot of rain on its NE leading edge. In the 24 hours to 2100GMT, 70.6mm fell at Cluanie Inn and 58.6mm at Achnagart, both of which are in the western Highlands.

[Simon Culling]

Hot on the heels of Storm Ali was Storm Bronagh that was initially named because it was expected to produce heavy rainfall. It did this, but also deepened quickly and gave some very squally winds on its cold front. The low moved from being just SW of Eire at 12GMT on Thursday to be just SW of the southern tip of Norway (at 969mb) a day later. The storm produced a lot of rain over Wales and much of the Midlands and northern England with some quite big totals - in the 24 hours to 0900GMT on Friday 21st we saw:

78.6mm at Capel Curig (NW Wales)
76.4mm at Tideswell (Derbyshire)
66.8mm at Sennybridge (mid-Wales)
62.6mm at Bala (N Wales)

The cold front produced a windy night over much of England + Wales with gusts to 50-60mph in many places and up to 82mph on the south coast. The weather turned quite a bit cooler after the cold front passed through but at least we had some sunshine on Friday. A frontal wave is approaching the SW of England today (Saturday 22nd) and we are enjoying a thoroughly wet and dismal afternoon here in Hythe with steady rain and a temperature of just 11*C. More rain for tomorrow as the wave develops into a low pressure system and colder as the wind swings round to the north.

The CET for September was 15.1*C (+1.1*C) up to the 20th and the EWR was 51mm also up to the 20th and this is 65% of the monthly total. This will soon be 100%+.

[Simon Culling]

The frontal wave gave two rather wet days in the south over the weekend, although it did clear Sunday afternoon to give a sunny albeit cool end to the day. The rain was mostly gentle, but gave 15-25mm to most places with the highest 48 hour totals to 06:00GMT Monday (24th Sept) I can find being 38mm at North Wyke (on Dartmoor, Devon), 29mm at Plymouth and 28mm at Bournemouth Hurn Airport. The highest temperature on Sunday was just 15.6*C at both Exeter Airport + Cardiff Bute Park.

The weather has now done a volte-face with a large high pressure system building in behind the wave (which developed further to our east and has given some nasty weather to southern Germany) and will take up residence near the south of the UK for the rest of this week. As at 06:00 this morning (Monday 24th), the synop map shows a 1040mb HP just off the tip of SW Eire and it will drift very slowly into southern England later today. This will give us here in the south a week of sunny days but cool misty nights - 'tis the season of mists and mellow fruitfulness' according to John Keats in his poem 'To Autumn'.

The first of the cold nights occurred last night with a general ground frost over most of the UK and an air frost in the more prone areas - such as RAF Benson (Oxfordshire) with -0.6*C and -1.0*C at Kielder Castle (Northumberland). it will probably be a little colder again tonight.

[Simon Culling]

High pressure has persisted near the UK with one centre moving away SE only to be replaced by another cell off the Atlantic today. The effect of this has been to change the wind direction today to N-NE and this has introduced much cooler air despite continued sunshine. Yesterday (Thurs 27th Sept) the temperature hit 24*C in eastern England, but the mercury has struggled to just 17*C today and there will be another general ground frost tonight. The first such frost occurred over Most of England + Wales on Tuesday morning with quite a few sites recording a ground temperature in the range -3*C to -5*C. The lowest air temperature I can find was -2.6*C at St Harmon in central Wales.

High pressure will persist to our west and south west over the next few days and this will likely lead to further reloads of cool air from the NW/N behind weak cold fronts - dry by the time they reach southern England. It should be fairly sunny at times, but the nights will be cool.

The CET for September was 14.3*C (+0.5*C) up to the 27th and the EWR was 66mm up to the 26th, which is 84% of the monthly average. Despite my earlier prediction, the quick change to an anticyclonic regime at the beginning of this week will result in a drier than average month overall.

[Simon Culling]

Friday night into Saturday (29th Sept) was a cold one over much of the UK (and Eire) for the time of year with another general ground frost, and an air frost at quite a few inland sites. A more SW flow into NW Scotland kept it mild there (mins of 9/10*C). The lowest temperatures I can find were:

-3.6*C at Katesbridge (Co Down, N Ireland - see below)
-3.2*C at St Harmon (Powys, central Wales)
-2.2*C at Mount Dillon (Co Roscommon, Eire)
-2.1*C at South Newington (Oxfordshire)
-1.8*C at Sennybridge (Powys)
-1.6*C at Mullingar (Co Westmeath)
-1.5*C at RAF Benson + Santon Downham

Ground temperatures were as low as -6*C at some sites. The figure of -3.6*C recorded at Katesbridge appears to be a new record low September minimum for Northern Ireland beating the current record of -3.2*C recorded at Magherally (Co Down) on 30/9/1991. Awaiting Met Office quality control on this.

[Simon Culling]

The cooler air has been replaced by milder south westerly winds in the last few days and the frosty nights have gone - for the time being. We have seen 20/21*C reached in the last three days in parts of England + Wales, even on the cloudier days. Friday will see more sunshine than today and a maximum of 21/22*C in the south, but a developing low just to the south of the UK on Saturday will re-activate a front over central parts and we will have a wet and cold day as northerly winds set in and we remain on the northerly flank of the low. This will herald a cooler spell for a couple of days with more frosty nights, but the mild (and potentially warm) southerlies will return in the middle of next week as ex Hurricane Leslie finally moves from the middle of the Atlantic to near the western side of the UK.

The final CET for September was 13.7*C (+0.1*C) and the EWR was 67mm which is only 86% of the monthly average. The linked Met Office summary gives mores details of the usual regional differences here in the UK in what was a fairly average month overall - at least it was a little sunnier than normal.

https://blog.metoffice.gov.uk/2018/10/0 ... tatistics/

[Simon Culling]

Saturday was indeed cool and wet over much of England + Wales with afternoon temperatures of 7-9*C and a stiff northerly breeze. The rain cleared away to give a cold and frosty night over most of the UK, although cloud and rain returned to the NW of Scotland by Sunday morning. The temperature fall to -4.3*C at Aboyne (in east Scotland) and to -3.6*C at Redesdale Camp in Northumberland. Further south, Rostherne (Manchester) reported-1.7*C as a minimum and Pershore (Worcs) -1.6*C.

Here in Hythe it was a sunny and cool day (max 15*C) with quite a lot of cirrus making the sunshine hazy at times, but it was a great day for a walk in the New Forest - we went to Denny Lodge where a muster of the wild horses was underway by the Verderers, the guardians of the forest. The attached photos give an idea of the beauty of this forest.

The rain that moved into NW Scotland on Sunday morning (7th October) is due to persist well into Tuesday as an 'atmospheric river' gets established over this area - a wriggling front aligned WSW to ENE (and stretching back into the mid-Atlantic) will have areas of rain move along it pushing a lot of rain onto the western side of Scotland - the Met Office is going for 150mm+ for the higher ground.

[Simon Culling]

It has been a very wet couple of days in western and north western Scotland as a line of rain has got stuck on the western slopes. The rain began around lunchtime on Sunday and has mostly persisted until Tuesday evening (with a break on Monday) when it finally dried out. Below are the 60 hour totals to 18:00GMT on Tuesday 9th October from the hourly observation totals. All these stations are on low ground (below about 200m amsl), so much more will have fallen on the west facing slopes.

221mm at Achnagart (Wester Ross)
177mm at Cluanie Inn (Inverness-shire)
174mm at Tyndrum (Stirlingshire)
148mm at Kinlochewe (Wester Ross)
128mm at Dunstaffnage (Argyll & Bute)

Not surprisingly, there has been some flooding:

https://www.bbc.co.uk/news/uk-scotland- ... t-45795343

In complete contrast to this, much of England + Wales had a sunny and warm day today (Tues 9th October) with the mercury reaching 21.8*C at St James Park in London. Here in Hythe there was not a cloud in the sky and it hit 19*C.

[Simon Culling]

Most of England + Wales enjoyed a late taste of summer yesterday (Wednesday 10th October) with wall to wall sunshine and very mild temperatures. Date maximums for mid-October are around 25*C at best and we got very close to that mark. The highest temperatures were in a NW-SE sector from inland southern England through London and into the Midlands. There was also an area of north Wales that was equally warm due to the fohn effect of the SE breeze over the Welsh mountains. The highest figures were:

25.3*C at Llansdwrn (on Anglesey - a private site, but run to Met Office standards)
24.6*C at RAF Northolt
24.4*C at Bridgefoot (Cumbria - also fohn effect from the Lake District hills)
24.2*C at Throckmorten Airfield (nr Pershore)
24.1*C at Porthmadog (NW Wales) + London Heathrow
24.0*C at RAF Mona (Anglesey), Kew Gardens, East Malling (Kent) + Pershore College
23.9*C at RAF Valley (Anglesey) + Wellesbourne (Worcestershire)

This mild air has come from a southerly flow sandwiched between high pressure to the east and a series of lows in mid-Atlantic and sadly is now slowly moving away east. A significant low will develop in the Atlantic and is forecast to have a central pressure of 938mb by midnight today (Thursday) which must be one of the lowest pressures seen near 50 degrees north on this side of the Atlantic. Thankfully, the low is expected to curve north to the west of Eire and the strongest winds will remain over the ocean. However, much of the western side of the UK will see a lot of wind and rain over the next few days as other lows follow this one. The eastern side of England will hang onto the warm air for a while, but the rain will eventually spread east.

[Simon Culling]

The low pressure (named Callum by Met Eireann) duly moved north to the west of Eire during Friday (12th October) giving a windy day to all of the UK. The synoptic maps give a central pressure of 938mb at both 18Z on Thursday and at 00Z Friday with the low slowly filling during the day. Thankfully, the strongest winds remained out to sea, but some stations reported wind gusts to 80mph. Of more concern is the trailing front that is in-situ over the western side of the UK and which will remain stationary into Saturday with rain pulses moving NE along it. Over 100mm of rain has fallen on Dartmoor (SW England) and the hills of south Wales today and this figure will reach 200mm by the time the front moves east on Saturday. There will likely be some flooding, but the generally dry summer and autumn means the rivers were lower than normal and the ground dry to depth before the rain started, so this might help reduce the flooding impact.

As a result of the stalled front on the west side of the UK, more eastern parts have a very mild southerly flow and now at midnight on Friday the temperature is still 19-21*C over a wide area of England - the highest figure I can find is 20.7*C at both St James Park in central London and Writtle in Essex. Before the rain moves east, the same area will have some very warm sunshine on Saturday and we could see the mercury hit 25/26*C before the cooler air out west moves in.

[Simon Culling]

The rainfall warnings for south Wales turned out to be very accurate as the rain area got stuck over western parts of the UK from Thursday through into Saturday and only moved slowly to the east today - to give us a wet Sunday morning here in Hythe. Rainfall totals for the 72 hours to 06:00GMT for Met Office sites in southern Wales were:

218.0mm at Libanus (Powys, 331m amsl)
143.0mm at Tredegar Bryn Back Park (Gwent, 380m amsl)
119.2mm at Sennybridge (Powys, 307m amsl)

Over 100m also fell on Dartmoor in the SW of England and in north Wales and into the Lake District. The rain in Wales has caused considerable flooding which is on-going as all this rain finds its way into the rivers.

https://www.bbc.co.uk/news/uk-wales-45838058

In complete contrast to this, the east of England had a wonderful sunny Saturday (13th October) with temperatures well into the seventies on the old Fahrenheit scale. The highest temperatures were:

26.5*C at Donna Nook (Lincolnshire) - beat the old date record of 25.3*C, set at Herne Bay in 2001.
26.0*C at Weybourne (Norfolk)
25.7*C at Holbeach (Lincs) + Cambridge NIAB
25.6*C at Santon Downham (Norfolk)

As suggested above, the rain band (still aligned SSW-NNE) is slowly moving east today giving more central (and later eastern) parts the rain and we will see a general drying out into the new week with much cooler temperatures.

[Simon Culling]

The rain band duly moved slowly east over the weekend and gave quite a lot of rain to the SE quarter of the UK - an area that has not seen too much rain recently. The rain was a bit hit and miss and the far SE got very little, but clumps of heavy rain moved NE along the trailing front and in the 48 hours to 09:00GMT on Monday 15th October, 47mm fell at Reading University, 46mm at RAF Northolt, 42mm at Hampton Water Works and 38mm at Woburn.

The warm air was never really dislodged from the far SE and returned NW again on Monday with further warm sunshine in this area today (Tues 16th), and today was the eighth day in a row when 20*C was exceeded somewhere in England - not bad for mid-October.

The CET for October was 13.0*C (+1.4*C) up to the 15th and the EWR was 54mm up to the 14th, which is 62% of the monthly average of 87mm.

Looking ahead, the weather will calm down with the nondescript stuff returning as high pressure reasserts itself. Temperatures look to be around average with the odd cool night and the usual autumnal problem of overnight fog.

[Simon Culling]

It has become settled and dry since early in the week as high pressure has persisted to our south and west, and this set-up looks like holding into next week, although the axis of the high will shift more to our west as a new (and bigger cell - 1045mb) develops in the eastern Atlantic. This will introduce colder air late in the week (Thurs/Fri) as the wind swings more to the north - some forecasts have sleet/snow to quite low levels in Scotland by Saturday (27th Oct).

Yesterday and today (Sat 20th Oct) have seen clear blue skies here in Hythe and quite warm in the sunshine (16/17*C), although we have had cool starts to the day with patchy fog around dawn - which is now 7am. Sunday and Monday will continue the sunny + mild theme, but I think there will be more cloud from Tuesday onwards and it will become a little cooler.

[Simon Culling]

The clear sunny days have continued in much of England and Wales with both Sunday and Monday being blue dome days - making four in a row here in Hythe. Sunday was rather warm (the max temp was 21*C in Suffolk), but after the passage of a weak cold front overnight, Monday was cooler with a high of only 15*C at Plymouth. I visited Hatchet Pond in the New Forest yesterday afternoon and it was still warm in the sunshine, despite the northerly breeze. I have attached a couple of photos below. Today (Tues 23rd Oct) we have a sheet of cirrus and cirrostratus, but there has still been plenty of hazy sunshine and it is a little warmer.

The trend over the next few days is for much colder weather to arrive, with a true northerly setting-in from Friday. This will give us a cold weekend with a few showers, which will begin to turn wintry in the North, even to low ground. Some of the models suggest a little sleet/snow further south, but snow is a very rare visitor to southern England in October, especially here on the south coast. That said, I can remember measuring 3cm of snow in Milton Keynes on the morning of the 29th October in 2008.

The CET for October was 12.4*C (+1.2*C) up to the 22nd and the EWR was 56mm up to the 21st, which is 64% of the monthly average. The former will fall quickly in the last 5 days of the month.

[Richard]

No autumn colours in those photos yet

[Simon Culling]

Hello Richard - the turn of the autumn colours has begun, but it is rather patchy at the moment and at Hatchet Pond it was not really evident last Monday- although a lot of the trees there are conifers or related species.

It turned a lot colder yesterday (Fri 26th Oct) as a cold front moved SE across the UK introducing a cold northerly flow and plenty of showers near to the coasts - with the SST's being above normal, the cold air passing over them brings some quite vigorous convection to the coasts facing into the wind. This morning (Sat 27th Oct) there are plenty of reports of snow to near sea level over Scotland and NE England with a few cm's in places. No snow for us in Hythe, and we will have a mostly sunny and cold day today (max about 8*C), but there may be a few cold showers this afternoon - I hope not as I will be at the Premiership game between Southampton and Newcastle at St Mary's Stadium in Southampton. I will need my beanie hat!!

The CET for October was 12.2*C (+1.2*C) up to the 25th and the EWR was 57mm also up to the 25th, which is only 65% of the monthly average.

It looks to remain cold for the rest of October with some cold rain early next week. Into November and we should see a warming trend back to near average temperatures, but the models are all over the place with regard to the weather.

[Simon Culling]

Yesterday (Sat 27th October) was indeed rather cold here in the UK - at match time (3pm) at St Mary's Stadium it was cloudy (thick Cu + Sc) and windy and just 6*C with a few light showers. Walking home along Hythe Pier I had to endure a steady 20-25mph northerly breeze and an ambient of just 5*C - and still a few light showers. Not pleasant.

The showers were heavier further inland and many sites in the English Midlands reported a maximum temperature of just 5*C on Saturday with some of the showers turning to sleet and wet snow at times. Today, Sunday 28th, will see the showers slowly fading away and increasing sunshine and slightly higher temperatures but this will give us a sharp frost tonight and into Monday - could see lows down to -5*C or so.

Looking ahead, a large low is currently developing over the northern Mediterranean and this will (unusually) drift north to be near southern Scandinavia by midweek keeping the UK in the cold air with still a few showers and rather cloudy. Some of the rain on this system will likely make it into the east of England at times. After this system fades we may well be looking to the Atlantic for our weather as the jet stream ramps up.