Tag Archives: Wanstead Park

London winter forecast 2016/17

Frost still lingers on my lawn as I write this winter forecast on the last day of the meteorological autumn. Last night’s minimum was -6.1C, the coldest night this year and, indeed, colder than any night last winter.

It would be very easy to get caught up in the hysteria that happens every November of what the winter will bring. Most of the hysteria comes from ‘coldies’, those folk that hope every winter will be the coldest and snowiest on record. I count myself among them.

screen-shot-2016-11-30-at-11-37-53
The north-west of England looks around 10C above average on December 9

But, despite hints from BBC weather forecasters that something maybe afoot in terms of something colder than usual from mid-December, years of disappointment have taught me to just take winter as it comes. Meteorological models this morning look anomalously warm for the first half of December, the UK being on the warm side of an anticyclone centred over France – the theme of so many winters I can remember.

The current phases of ENSO and QBO suggest that their influence on our winter this year will be far less marked than last year. Looking at teleconnections with a slight La Nina and the current QBO cycle have revealed winters that were fairly uninspiring though by no means write-offs for snow, two examples in the case of QBO being 1985/86 and 1990/91 – both had very cold Februaries.

Before I got too bogged down with trying to find patterns here I decided to move on to my more traditional pattern-matching.

Before I trawled through the figures my initial gut reaction to this winter was that it would be the coldest for at least four years – a not-too-difficult feat giving the mildness of the last three winters which saw very little in the way of snow.

winter201627The overall mean temperature for December, January and February came out at as 4.2C1.2colder than the 1981-2010 average, with average precipitation. 

rather cold winter, over three months doesn’t tell you much. A very mild and stormy December could mask a dry and notably cold February. This makes it worth looking at the individual months of each winter.      

december2016january2017february2017

There is a lot of spread in the above tables. Considering them altogether I would guess winter will unfold in the following way:

December to start mild, possibly becoming very mild, before beginning to turn very cold mid-month. This pattern will persist, with varying intensity through into January which could also be very cold. Milder conditions to follow in February though this will probably end a fairly average month and drier after a slightly wetter than average December and average January.

As well as my method of using rainfall and temperature I also considered other methods. One was Russian research that states that the weather pattern in the winter will be the opposite to the weather on September 17th and November 7th. This autumn September 17th was N’ly and November 7th was NNW’ly. So, this would suggest a continental flow from S and SSE.

You can read the method of how I reached my conclusion here.

October 2016: average temps, dry

October 2016 was yet another dry month, a pattern that has emerged since the middle of June. Just 52 per cent of the October average was recorded.

sunny
October saw many pleasantly sunny days

The monthly mean finished 11.5C, 0.3C above average and ending a three-month run of warm temperatures.

Some 105 hours of sunshine were recorded, 98 per cent of average

Air frosts: 0, Ground frosts: 0

So what has November got in store weatherwise? The models on the 1st suggest an anticyclone anchored to our west over the Atlantic will bring a regime of, at times, chilly northerly winds and the potential for rainfall, much probably in the form of showers, driven by low pressure in the North Sea. Where skies clear at night there will be potential for the first air frosts of the autumn.

Beyond the grasp of the models my long range outlook method suggests an average or cold month is most likely: average and cold are both 30 per cent probability. Rather cold and severe are both 20%! There appears no chance of anything mild.

Rainfall appears that it will be skewed toward something above average at 40 per cent, though average and below average are both 30 per cent.

Sunshine looks average at 57 per cent probability.

So, to sum up, we’re looking at a mean of 6.8C, rainfall: 55mm, sunshine: 41hrs.

holes
Numerous holes dug by squirrels appeared in October. The squirrels have no more an idea than we do whether winter will be cold

Here follows the full weather diary for October…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Rainy start with showery bursts to 11.25am then through afternoon mostly cloudy.
2nd: Sunny but chilly, feeling very autumnal. Clearing into the evening with a cold night to follow.
3rd: Sunny, gin clear all day until 2.08pm.
4th: Another sunny albeit slightly hazy start then patchy cumulus. Warm in the sunshine even with a easterly breeze.
5th: Sunny start though breezy and with quite a few cumulus around. Cloud streets observed at 10.30am, the cloud tending to decrease and completely melt away by 4pm.
6th: Sunny start but with much cloudier spells at times. Warm in the shelter.
7th: Cloudy all day, the cloud thick enough at lunch time for drizzle that damped the ground.
8th: Cloudy with bursts of light drizzle in the morning, some brightness. A heavy shower at 2pm was brief then cloudy. Clear and cold overnight.
9th: Sunny until 2pm with patchy cumulus – a really glorious morning. Sunny spells in afternoon with cold night to follow.
10th: Sunny with just patchy cirrus first thing. Thick patches of alto-cumulus drifted across from time to time. Cold overnight.
11th: Sunny with patchy cumulus which melted away through the day. Showers after dark, one at 2330z.
12th: Cloudy and damp start. Short, sharp shower at noon then mostly cloudy.
13th: Rainy , wet start thanks to a streamer of moderate to heavy showers.
14th: Cloudy am but with lots of sunshine mid-morning before clouding over again though staying bright.
15th: Bright start but with lots of cloud pushing in and light burst of drizzle at noon. Cloud thickened before rain moved in after 5pm and fell intermittently through the night.
16th: Damp start as the remnants of the overnight rain cleared away, then becoming brighter at 11.15am. Sunny spells for a time before turning cloudier with some very sharp showers on yet another convergence line.
17th: Cloudy start but soon brightening up with some pleasant sunny spells. Heavy burst of rainfall at 5.30pm with more showers at midnight and early hours.
18th: Cloudy though quickly turning bright and breezy with long sunny spells after clearance of the cold front.
19th: Bright start though more cloud around than sun all day. Feeling colder than of late.
20th: Bright and breezy with variable cloud and sunny spells. A short shower at 2pm damped the ground. Clear spells overnight made it chilly. A shower at 9.30am.
21st: Cloudy and chily start.
22nd: Cloudy and cold start, brief clearance at 11am then sunny spells.
23rd: Sunny and clear to start though cold. Sunny spells into the afternoon. Cloudy overnight.
24th: Cloudy and cool during the day and overnight.
25th: Dull and cloudy with only limited brightness. Clear early evening with temp falling before it turned misty. Cloud pushed in raising the temperature.
26th: Cloudy start and turning very dull before bright spells spread in at noon.
27th: Cloudy though getting brighter through the morning with a brief clearance at noon, then bright and sunny intervals.
28th: Sunny and very mild to start. Sunny spells through the day.
29th: Cloudy start with bright intervals after midday. Clear spells after dark with fog forming after 11pm which gave a foggy start.
30th: Foggy start then cloudy and miserable.
31st: Fog to start then clearing at 11am. Gorgeous sunny day thereafter.

September 2016: very warm, very dry

Last month was the second warmest September in a local record going back to 1797! The monthly mean finished 17.8C, 2.4C above average. Despite being an ‘autumn’ month September was actually a full degree warmer than June!

screen-shot-2016-10-01-at-11-55-19
September 2016 was the second warmest in a local record back to 1797, though we’re talking by fewer than tenths of a degree.

The hottest September day since 1959 was recorded on the 13th when 33.1C was reached, the sixth equal hottest in the local daily record back to 1848.

The month also saw the warmest minimum recorded since 1959 when the mercury failed to fall below 18.7C on the 6th.

It was another very dry month, the third much drier than average month in a row: just 27.7mm fell, 24 per cent of average, making it the driest September since since 2007 and the 12th driest in the local record.

Like August, the month only falls down in terms of impressiveness when sunshine hours are considered. Some 119 hours were recorded, that’s 85 per cent of average, making it the dullest September for 15 years.

Air frosts: 0, Ground frosts: 0

So what has September got in store weatherwise? The models on the 1st suggest that a large Scandinavian high will become established to our NE bringing lots of settled weather and showers on coasts. There’s obviously the chance of trough disruption as the month progresses if the anticyclone’s influence declines.

Beyond the grasp of the models my usual long range outlook method falls down this month due to September’s warmth and dryness – there is nothing within  +/- 10% of September’s statistics. I would guess, however, that we are looking at another drier than average month with frost becoming a risk as the month progresses where skies clear. There is also the chance of more pleasant autumn days where skies are clear during the day.

My September outlook for temperature was poor. I predicted a mean of 15.3C (outcome: 17.8C). It was much, much drier than I thought: 300mm (outcome: 27.7mm). Sunshine was poor: 140 hours (outcome: 119 hours).

Here follows the full weather diary for September…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Sunny start but cloud gradually increased until it was overcast by 6pm. Clear spells overnight but warmer than previous nights.
2nd: Cloudy though some brighter intervals.
3rd: Sunny start, cloud began to pile in at 12.30pm with rain arriving at 5.30pm, this fell through the evening with some showers in the early hours.
4th: Bright, breezy start but rapidly turning cloudy and dull. Some rain overnight.
5th: Light rain and dull to start – this quickly clearing to cloud by 3pm. Things remained cloudy with a muggy night.
6th: Cloudy, dull and muggy start after warmest September night on record. Another warm night though muggy.screen-shot-2016-10-01-at-12-22-03
7th: Cloudy to 11am though sun breaking through as drier air arrived. Feeling humid.
8th: Sunny start but with plenty of cumulus, this quickly decreasing to leave clear sky.
9th: Cloudy morning though sky seemed to periodically clear of low cumulus before becoming overcast and very breezy in the afternoon. Some rain overnight and just before obs time.
10th: Cloudy start with patchy light rain, this briefly turning  heavy at 1pm  before turning occasionally moderate. Dreadful afternoon after recently. Clearing overnight to leave a sunny start.
11th: A glorious sunny day with only the odd patch of cirrus.
12th: Bright start with some sunshine, clouding over with a few splodges of rain with warm front. Then sunny and very warm.
13th: Sunny start with a few cirrus and castalanus around. Breezy at times with the thermals. The warmest September day since 1959 and 6th equal warmest since 1848.screen-shot-2016-10-01-at-12-13-54
14th: Sunny start with a few cirrus. A few patches of alto-cumulus later. Very warm but not as hot as yesterday. Warm, pleasant evening.
15th: Sunny with a few wispy cumulus, clearing to hot sunshine. Some alto-cumulus developed at 2pm and towering cumulus could be seen in distance. Thunderstorms reporting to NW of London. Cloudy and warm overnight with eight peals of thunder in the early hours and heavy rain.
16th: Light to moderate rain through the morning, petering out at 1.30pm.
17th: Cloudy, cool and breezy all day, at times dull.
18th: Cloudy all day, a bit warmer than the previous two days.
19th: Cloudy start though with sun breaking through briefly at 11am until 1pm then cloudy again. Rain at 1am that didn’t last long enough to register.
20th: Cloudy and fairly calm – a nothing day with odd very light drizzle.
21st: Bright start with cloud breaking to long spells of sunshine before more cloud moved in. Warmer than of late.
22nd: Cloudy but  sun broke through giving pleasant afternoon and cool overnight.
23rd: Sunny, gin clear and cold start. Just a few fair weather cumulus through the day.
24th: Sunny start with cloud decreasing. Very warm in sun but cloud and breeze built through the day. Overnight light rain between 6am and 9am.
25th: Bright start after overnight light rain.
26th: Bright start with a few cloud breaks here and there. Heavy shower at 12.15pm with further threat of rain but stayed dry.
27th: Bright start with signs of a cold front moving in from south then cloudy.
28th: Sunny start with patchy cirrus, this tending to thicken at lunchtime to turn mostly overcast with humidity increasing. Breeze also picked up with reappearance of sun mid afternoon. Cloudy, very mild and breezy rest of the day.
29th: Cold front and brief heavy rain swept in at 10.03am. Then intermittent falls until 11.23am.
30th: Sunny, gin-clear start, patchy cumulus bubbling up at 10.30am. Cloud grew thicker around 12 noon with brief shower at 1pm. Then sunny spells and cloudier periods. Another shower just after nightfall then clear. Cloud moved in after 2am with another shower. Early sunshine  gave way to moderate showers around 9.45am.

A mostly quiet and dry autumn on the way?

I don’t usually bother trying to forecast autumn or spring given that there is far less interest in them than winter and summer. However, given the heightened interest in this year’s hurricane season and emboldened, perhaps foolishly, by my reasonably correct summer forecast I decided to have a look at the stats and see if I can find any signs where autumn in east London may be headed.

Using the methsummer simsod for my seasonal forecasts resulted in a shortlist of 26 summers that were similar to 2016.

Because the NOAA ENSO index only goes back to the 1950 I decided to disregard all years prior to this date to try to make any results more reliable. This narrowed down the list to 11 years.

With these considered I then searched for years that had a similar ENSO index to June (0.1 – neutral) with a tendency to turn negative (La Nina). This narrowed the field further to three years: 1999, 1992 and 1964. However, the only year that is showing signs of being similar with regard to where the ENSO index is forecast to be heading is 1964.

Although, so far, there has been an uptick in hurricane activity similar to 1964 there is, of course, the added consideration that Saharan dust is playing a part in impeding the formation of these tropical storms in the Gulf of Mexico – something the weather models seem to struggle to get a grip on.

With this in mind perhaps there will also be lower than usual instances of these storms crossing the Atlantic to affect the UK: hence a quiet autumn though, on a national scale, interpersed with the odd interest from the Atlantic. weather notes 1964In London, perhaps we can expect something very similar to what is listed on the excellent website: http://www.london-weather.eu/article.103.html

autumn 1964

 

Summer 2016 review

Summer 2016 turned out to be a very decent season overall, the mean temperature of 18.7C (1.1C above average) made it the sixth warmest summer since 1797.summertop20

While it wasn’t quite up there with the hot summers of 1976 and 2003 it still produced some notable records. The stormy beginning to June effectively ended with the Brexit vote, a period of 24 hours that coincided with the highest daily rainfall this area has seen since at least 1959.

The multi-cell thunderstorm in the early hours of June 23rd produced 60.8mm of rainfall, nearly half of the month’s total which became the third wettest June in a record going back to 1797. The high rainfall was in complete contrast to July and August and helped skew the overall figure: 168.6mm is 114 per cent over average summer rainfall.

sunWith so much rainfall overall sunshine was affected with only 451 hours recorded, just 80 per cent of what can be expected in an average summer.

July produced another record, this time the highest overnight minimum recorded since 1959. The minimum of 21.1C was recorded during the early hours of the 20th – coming hours after the hottest day of the year: 33.5C – the 14th hottest day on record.

The warm and very dry theme continued into the final month of summer with the warmest August for 12 years, the 10th warmest and 12th driest since 1797.

My summer forecast, when the monthly probabilities are considered, was broadly correct though I didn’t estimate correctly just how warm it would be.

Mean forecast: 16.7C (outcome 18.7C)
Rainfall forecast: 166mm (outcome 168.6mm)
Sunshine forecast: 546hrs (451.4hrs)

summer2016mean

summer 2016 rain

summer 2016 sun

 

 

August 2016: warm and very dry

Though there were no records broken August 2016 goes down as a mighty fine summer month, the warmest for 12 years. The mean of 19.5C was 1.3C warmer than average and only 0.1C cooler than 2004.

wanstead park
Grasslands around Wanstead Park have gradually turned brown because of the lack of rainfall

The month ended a three-year run of poor or so-so Augusts: in terms of mean temperature the month was the 10th warmest in a local series going back to 1797.

It was another very dry month: just 11.9mm fell, 24 per cent of average, the driest August since 2003 and the 12th driest in the local record.

The month only falls down in terms of impressiveness when sunshine hours are considered. Some 192 hours were recorded, the 59th sunniest since 1797 – 1995 had 80hrs more sun.

Air frosts: 0, Ground frosts: 0

So what has September got in store weatherwise? The models on the 1st suggest the month will start mixed, though any precipitation will be below average. Temperatures remaining on the warm side.

warmest augustsBeyond the grasp of the models my long range outlook method is again hampered by a very dry August. However, the data I do have suggests an average month at 100 per cent probability.

A wetter than average month looks most likely at 75% probability.

The rainfall probability makes me wonder whether we are in for a very unsettled second half of September, the Atlantic cranking into life with the remnants of tropical storms and hurricanes having an ever-increasing influence as the month progresses.

So to sum up: mean 15.3C (average), rainfall 162mm (300%), sunshine 140 hours (100%).

driest augustMy August outlook for temperature was good. I predicted a mean of 19C (outcome: 19.5C). It was drier than I thought: 30.3mm (outcome: 11.9mm). Sunshine was poor: 239 hours (outcome: 192 hours).

Here follows the full weather diary for August…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Cloudy start to 1pm. Rain started at 5pm through to 10pm. A brief interlude before more light to moderate rain through the night 4.30am, then drizzle
2nd: Damp, miserable start – the rain became light to moderate in the early afternoon before drying up – very high dew points through the day.
3rd: Bright and breezy with variable cloud.
4th: Bright start with variable cloud and sunny spells.
5th: Good sunny spells all day – perfect summer’s day, not too much humidity – though an isolated shower passed over at 8pm.
6th: Sunny, clear start. Lots of sunny spells during the day.
7th: Bright start though very breezy. Cloud decreased through the day to leave a gorgeous late afternoon and evening.
8th: Sunny, clear start with lots of fair weather cumulus throughout the day. Cloudier spells mid afternoon.
9th: Sunny with fair weather cumulus up until noon then cloudy afternoon.
10th: Sunny with fair weather cumulus, variable throughout the day. Breezy.
11th: Cloudy start with very brief light rain, barely enough to damp ground. Some sunny intervals later and bright and warm.
12th: Sunny start with a few clouds. Turned gin clear at 11am and stayed clear all day. Feeling hot.
13th: Bright start but turning cloudier. Sunny intervals PM.
14th: Cloudy start breaking to some long sunny spells. Feeling very warm in the sun.
15th: Bright start soon turned sunny with a clearance at 1pm.
16th: Bright start though a lot of haze around. Sunnier later though still hazy.
17th: Sunny with patchy cloud to start, this clearing late morning to leave a clear if rather hazy afternoon.
18th: Sunny if a bit hazy to start, this tending to decrease to leave warm sunshine.
19th: Cloudy with rain threatening. Low cloud at Stansted. Brief rain in afternoon then cloudy.
20th: Dull and overcast at 9am. Burst of heavy rain at 10.15am clearing to sunny spells at noon 30. Rain between 7pm and 8pm and 3am and 4am.
21st: Bright start. Sunny intervals till 3pm then sunny spells.
22nd: Bright after earlier rain at 0719 then sunny spells.
23rd: Clear and sunny start with a few cirrus clouds through the day. Hot.
24th: Sunny, gin clear start. Patchy cirrus through the day. Hot.
25th: Lots of altocumulus and sunny spells but felt sultry due to high dew points.
26th: Cloudy start but gradually decreased to leave clear pm.
27th: Overcast but bright start. Brightness through the day but hazy. Some heavy storms further north.
28th: Overcast until early afternoon, 5 minute shower at 2pm then sunny intervals..
29th: Bright start then sunny spells and cirro cumulus gradually clearing to leave a sunny evening and clear night.
30th: Clear and sunny start.
31st: Bright start though cloud filling in by 3pm, clearing again at 8.30pm

July 2016: rather warm and very dry

There was plenty of interest in the weather last month even though the overall stats suggest July 2016 wasn’t that remarkable.

july 9 sky
The sunset on July 9th was spectacular

Most notable was temperature: the warmest minimum on record for this area (21.1C) was recorded during the early hours of the 20th – coming hours after the hottest day of the year: 33.5C – the 14th hottest day on record. The mean temperature of 19.5C  was a degree warmer than average, the 18th warmest July since 1797.

Rainfall was very sparse. A total of 17.3mm fell during the month, that’s 40 per cent of average, the driest for six years and the 19th driest in the series going back to 1797.

After a very dull start to the month sunshine was always going to struggle: just under 172 hours were recorded – that’s 89 per cent of average and marginally down on last July.

Air frosts: 0, Ground frosts: 0

record warm min
The temperature didn’t fall below 21.1C on the night of 19th July, making it the warmest minimum on record in this area back to 1959

So what has August in store weatherwise? The models on the 1st suggest the month will start with a mixture of sunshine and showers. At the end of this week there are indications of a change to warm and later very warm weather.

Beyond the grasp of the models my long range outlook method is hampered this month because of the very dry July. However, the data I do have suggests a rather warm month at 50 per cent probability. The ‘worst case’ scenario suggests something average, a contrast to  the past couple of Augusts which have been poor. Perhaps we can look forward to another reasonable summer month, defined by plenty of fine, at times hot, weather – though anyone looking for unending days of 30C and higher will be disappointed.

A dryer than average month (possibly very dry) looks most likely at 50% probability. A very sunny month looks most probable.

So to sum up: mean 19C (0.8C above average), rainfall 30.3mm (60%), sunshine 239 hours (123%).

hottest dayMy July outlook for temperature was good. I predicted a mean of 18.8C (outcome: 19.5C). Rainfall was very poor: 50mm (outcome: 17.3mm). Sunshine not badr: 171.9 hours (outcome: 190 hours).

Here follows the full weather diary for July…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Cloudy with sunny intervals. Some sharp showers.
2nd: Bright start though breezy. Very heavy shower at 1740.
3rd: Sunny though with lots of cumulus.
4th: Sunny, gin clear start though cumulus rolled in at 1.30pm.
5th: Cloudy start with very brief, very light drizzle though with sunny breaks developing.
6th: Hazy mix of cirrus and cumulus gradually decreased to a clear sky by 1pm. More cumulus bubbled up later but still mostly sunny and low humidity.
7th: Sunny start with lots of cumulus, cirrus and stratus around. Sunny spells through the day.
8th: Cloudy and breezy start.hants
9th: Bright start with sunny spells but also lots of cloud. Amazing sunset with fronts coming in.
1oth: Cloudy start with light rain spreading in but only lasting for 40 minutes. Some sunshine in the afternoon though was breezy.
11th: Cloudy start with heavy showers early afternoon.
12th: Sunny start though with plenty of cloud which bubbled up and gave heavy showers from 11.30am. More showers in the afternoon – miserable.
13th: Bright and sunny to start that cloud gradually built before heavy showers hit at 2pm, these lighter over Aldersbrook.
14th: Sunny, bright start with sunny spells, tending to turn cloudier.
15th: Bright start but cloud piled in and breeze picked up.
16th: Sunny start with lots of cirro-cumulus. Cloud tended to build at times and a front passed over at 4pm. Warm evening and night.
17th: Bright start though with lots of heavy cumulus around. This tended to break up at intervals during the day, making it feel hot in the sun because of the high humidity.
18th: Sunny start with patchy cirrus and cumulus. This decreased as day wore on leaving a hot day. Felt almost airless with variable cloud.
19th: Sunny with decreasing cirrus to start to leave a gin clear day. Breeze picked up at noon meaning it wasn’t as warm as it could have been.
20th: Sunny but hazy start but with more of a breeze than yesterday. Cloud tended to fill in but then burnt off to leave another hot day.
21st: Sunny but cooler start than yesterday with lots of milky cumulus around.
22nd: Cloudy start after overnight rain. Sun breaking through at 12.30pm.
23rd: Cloudy start with spots of drizzle at 11am then slowy getting brighter with evening sunshine.
24th: Cloudy start with early showers breaking to sunny spells.
25th: Sunny start with variable amounts of cloud through the day. Feeling cooler.
26th: Sunny start though with cloud bubbling up through the morning. Overcast by 2pm.
27th: Cloudy and damp with light rain before and after obs time.
28th: Sunny periods with variable cumulus
29th: Cloudy start with brief rain showers in Chigwell. Sky broke to allow long sunny spells before it clouded over again. Rain shower at 9pm.
30th: Cloudy and overcast start. Long sunny spells into the afternoon.
31st: Sunny start though more cloud tending to bubble up in the afternoon.

June 2016: extremely wet, dullest on record

Storm clouds gathering was a common sight in June 2016, but enough about the tumultuous political situation…

lake
The levels of Heronry pond have benefited immensely from the rainfall which was 2.5 times the average in June

For anyone looking for summery weather there was little to cheer about. For sunshine the month was the dullest June in a record going back to 1797. Just 96 hrs were recorded – which is just over half what we can expect in an average June.

Most notable was the rainfall: just over 139mm fell which is 272 per cent of average, and the third wettest since 1797. Only 1903 and 1860 were wetter. The month also saw the record broken for highest daily rainfall in a 24-hour period. A multi-cell thunderstorm in the early hours of the 23rd saw 60.8mm fall, most of it in two hours, bringing flash floods to the surrounding area.

fax
The synoptic situation at midnight on June 23 when the heaviest rainfall this area has seen since at least 1960 fell

With the lack of sunshine and copious rainfall it is, perhaps, surprising that the mean temperature for the month finished just above average: 16.8C is 0.7C above the June average. The warmest day was the 10th with 25.3C recorded – only one other day saw the mercury exceed 25C – very unusual for this time of years.

Air frosts: 0, Ground frosts: 0

So what has July got in store weatherwise? The models on the 1st suggest more of the same weather that we have seen during the last third of June. Sunshine and showers with the occasional ridge possibly calming things down for a few hours.

blake
Roads in Wanstead were turned into rivers in the early hours of June 23rd

Beyond the grasp of the models my long range outlook method suggests a rather warm month at 50 per cent – so given the cool start perhaps we can look forward to something summery in the final half to one third? Rainfall and sun looks inconclusive so I would guess average. Because of the high rainfall last month I think my long range method falls down.

A slightly wetter than average month looks most likely at 50% probability. Sunshine probably about average.

So to sum up: mean 18.8C (0.3C above average), rainfall 50mm, sunshine 190 hours.

My June outlook for temperature was good. I predicted a mean of 16.9C (outcome: 16.8C). Rainfall was very poor: 38mm (outcome: 139mm). Sunshine very poor: 178 hours (outcome: 96 hours).

Here follows the full weather diary for May…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Cloudy and cool all day.
2nd: Cloudy and cold all day, brief brightness at 11am.
3rd: Cloudy and cool all day, limited brightness late morning. Cloudy overnight with limited breaks – air was very humid with warm front and visibility severely limited.
4th: Cloudy all day though cloud was lighter and air felt warmer because of the warm front that came in yesterday from Europe. Brief milky sunshine at 7pm.
5th: Cloudy up until 9.30am when the cloud began to thin. Sunny spells from 11am before a clearance at 1pm interspersed with occasional cloud.
6th: A gloriously sunny day all the way through. A lovely evening too.

sunsetflats
Sunny sunsets were rare in June

7th: Sunny start but cloud rolled in at 1.30pm with thunder heard all around Wanstead. Some serious flash flooding in Croydon. Highest official total was over 40mm in Kenley. Just 1.7mm during the day but trough brought rain at 5am, about 3mm.
8th: Sunny start but felt very humid and oppressive. A thunderstorm skirted Wanstead at 1.40pm with thunder and much rain in Chigwell, not much in Wanstead. More thunder at 2.10pm. Rain came and went for rest of day until 7pm – very little upper air movement. Mostly cloudy overnight.
9th: Cloudy start but some sunny spells developing.
10th: Cloudy start but soon decreased with long sunny spells developing. Lower humidity so felt pleasant.

chigwellrain
Heavy rain in Chigwell

11th: Cloudy and humid start with very heavy rain at 3pm. This lasted for 45 minutes. More rain fell sporadically through the day, evening and overnight.
12th: Cloudy after moderate rain. Showers and longer bursts of rain returned before a brief clearance at 3pm. More showers piled in with a real corker to the north of Wanstead.
13th: Damp start soon led to light rain, turning persistant at 11am. Then outbreaks of rain throughout the day, evening and overnight.
14th: Light rain to start but this quickly gave way to heavy showers all day. Some brightness at 6pm then turning drier overnight. Gin clear dawn.
15th: Sunny start but with lots of convective cloud. Some drizzle but a heavy shower stayed to the east of Ilford.
16th: Bright start with sunny spells, more breeze than recent days
17th: Lots of cloud around though sunny spells arrived early afternoon. Then showers between 5 and 6pm.
18th: Cloudy with spots of drizzle. Feeling cold all day – a maximum of only 16.5C.
19th: Sunny start but cloud gradually increasing all afternoon. Rain by nightfall that fell intermittently for hours. Rain again at obs time.
20th: Rain to start that lasted, with variable intensity, through the morning. Sunny spells from mid afternoon.
21st: Sunny start with just a few cirrus and cumulus, this tending to increase through the morning to leave an overcast afternoon. Cloudy overnight – a few spots of drizzle on school run as frontal wave started to move across UK.
22nd: Cloudy start with warm sector drizzle. Showers developed at 11pm, much thunder and lightning and the rain turned really heavy through the early hours.

rainjune
Extremely heavy rainfall during the early hours of the 23rd

23rd: Cloudy and humid to 1pm. Showers at 3pm.
24th: Sunny with variable cloud. Feeling humid in the sunshine.
25th: Bright start with sunny intervals. Light shower at midday. Thunderstorms at 2pm, 4pm and 9.30pm.
26th: Sunny spells though significant cloud at times. Rain between 4 and 6pm.
27th: Mostly cloudy though with some brightness after noon. Warmest point was in the evening at 7pm.
28th: Bright though cloudy start. Some sunny intervals but rain late afternoon into the evening. Cool overnight.
29th: Cloudy and breezy, some rain in the air early afternoon and again in the early hours
30th: Cloudy with slight breeze. Some light rain in the early hours.

Summer forecast 2016: yo-yo weather

The cold start to June may soon be a distant memory once summer proper gets going in east London. But rather than a succession of prolonged hot, dry spells it’s looking like the season overall will be broadly average – you will hear the old saying: ‘an English summer consists of three fine days and a thunderstorm’ more than once this year.

Heavy shower cloud looking east over Wanstead Flats
Three fine days and a thunderstorm – the typical English summer

Looking at summers back to 1799 I’ve tried to find a pattern linked with a declining El Nino. And failed to find anything conclusive. With ENSO forecast to be approaching neutral by August I decided to discount it completely, instead relying on pattern matching of meteorological data from this area for March, April and May stretching back to 1799.

The mean for the spring season was 10C with 156.4mm of rain and 455 hours of sunshine.

If you take into account all years that were within +/- 10 per cent of these figures, for rainfall and then mean temperature, some 36 ‘best fit’ years emerged, far more than my previous two attempts to forecast summer. The years, ranging from 1805 through to 2007, saw all manner of summers – only one was a real corker, 1825, but most were fairly nondescript average affairs. As an average this summer could be expressed as: Mean: 16.7C (just above average) Rainfall: 166mm (exactly average) Sunshine: 546hrs (about average)

Or, expressed in probabilities, I concluded the following:

summer 2016 probs

 

 

From the above you could deduce that the next three months will be slightly warmer than average, with average rainfall and sunshine.

Last year I tried to decipher, with fair success, when hot spells would occur. However,  looking at the data of these 36 summers very warm, dry spells happened through the three months – it was impossible to find any exact pattern to when it would be warm and dry.

Instead I’ve broken down the summer into June, July and August probabilities.

Looking at June, considering this cool and cloudy start, I would guess that we can look forward to a few very warm, thundery spells – a repeat of the Spanish plumes of the past couple of years.

june 2016 probs

Considering the above data perhaps there is a greater than evens chance of some thundery activity – and the nature of thunderstorms mean you can get a deluge or stay relatively dry / average. Sunshine average.

On to July. After a ‘rather warm’ June I wonder if the ‘return of the westerlies’ will happen just in time to affect this month?

July 2016 probs

The above chart would suggest that July will be classically average overall. Fine, not too hot spells, with occasional depressions bringing cooler weather and showers.

On to August. This month has been a real disappointment the past couple of years. However, I think this year August may offer a bit more in the way of sunny weather.

August 2016 probs

Looking at the above probabilities there seems a fair chance of something average to rather warm overall. With rainfall below average and average sunshine I wonder if there will be two or three fine spells throughout August – perhaps more?

So, all-in-all, summer looks a mixed bag. How this summer will fair obviously only time will tell. One could argue that what I’m forecasting is just climatology which has a good chance of being correct should no external influences, such as a huge eruption on Mount Etna, have a bearing on the end result.

* Taking into account the fact that temperatures in London are up to 0.66C warmer than they were 100 years ago I have added 0.66C to mean temperatures before 1915.

** Obviously, in the event of a series of direct hits from thunderstorms, my rainfall estimate could be hopelessly short – a symptom of abundant solar energy at this time of year which creates a ‘noisy’ atmosphere compared with winter.

*** The 1981-2010 average mean for summer in this region is 17.6C, with 144.9mm of rain and 564 hours of sunshine

May 2016: rather mild with average rain

A stunning first week of weather in May 2016 probably led a few people into believing that we were in for a glorious start to the summer. But the second Sunday in the month when temperatures reached 27.1C under 13 hours of sunshine was about as good as it got.

view
May 10th 2016 looking toward Crown Hill from Dunton in Essex

The warm first week helped maintain the mean temperature to finish above average: 14.3 which is 1.2C warmer than average, the warmest May for five years.

Though on paper rainfall looked a little under average 44 per cent of the monthly total fell on the last day. Some 43.4mm fell during the course of the month, that’s 85% of what we can expect during a normal May.

Sunshine was about average. Some 184.5 hours were were recorded, 101% of what we can expect to see during an average May.

The wettest day occurred during the meteorological 24hrs of the 30th (09-09 31st) with 14.7mm, rain associated with a depression in the North Sea. Incessant cloud held temperatures down to 12.6C, the coldest May 31st for 36 years!

convey
A conveyor belt of rain brought the coldest May 31st for 36 years

Air frosts: 0, Ground frosts: 5

So what has June got in store weatherwise? The models on the 1st suggest only slow changes in the next 3-4 days. These changes revolve around the release of low pressure from Europe towards high pressure later next week. This process begins as high pressure also begins to build down from the north at the weekend with several days of fine and increasingly warm conditions as the cool NE’ly flow is lost to warmer winds from the SE or south. Then next week with higher pressure over Europe and low pressure drifting slowly north or NE towards the west of the UK it could become very warm and humid in places and as that low to the west pushes troughs towards us from the SW it could feed some thundery rain and storms up from the SW at some stage by midweek. The pattern thereafter appears quite mixed. GFS suggests a more traditional pattern of low pressure to the NW and higher pressure to the SE with SW bringing rain at times to the north and west while the south and east see the best of prolonged dry and warm periods between intermittent rain.

high
High pressure to the north of Scotland brought often miserable, overcast weather to our region

Beyond the grasp of the models my long range outlook method suggests an average to rather mild month. The highest probability is 29% for something a little above average and rather mild. A little below average and mild both come in at 14% probability. Something cool or very cool comes in at 7%. If you combine the first two probabilities together something just over average would come in at 58%

A dryer than average month looks most likely at 57% probability. Sunshine probably about average.

So to sum up: mean 16.9C (0.8C above average), rainfall 38mm, sunshine 178 hours.

My May outlook for temperature was poor. I predicted a mean of 12.8C (outcome: 14.3C). Rainfall was also poor: 58mm (outcome: 43mm). Sunshine was good: 184.5 hours (outcome: 179 hours).

 

Here follows the full weather diary for May…Full stats for the month here:http://1drv.ms/1rSfT7Y

1st: Sunny start though with cirro cumulus around. Cloud tended to thicken up through the day to leave overcast late afternoon. A warm night followed.
2nd: Cloudy with spits and spots of rain to start. Some bright spells late morning but then overcast and some rain at 6.40pm – a decaying front gave little rain. Clearing overnight and cold.
3rd: Sunny with fair weather cumulus developing.
4th: Sunny, gin clear start with just a few fair weather cumulus developing. Clear and cold overnight.
5th: Sunny and warm, some hazy cloud in the afternoon.
6th: Sunny start though turned much more hazy than yesterday. Feeling humid.
7th: Hazy sunshine to start with high level strato-cumulus bringing cloudier periods.
8th Sunny start with just a few clouds. Air much clearer than yesterday and hot by mid afternoon on Canary Wharf.
9th: Cloudy start but became sunny late morning. Rain arrived 5pm, turning moderate 7.30pm and outbreaks through the night.
10th: Light rain to start, this turning moderate at times throughout the day, though petering out at 2.30pm.
11th: Dull, damp start that went into 11am. Heavy showers developing that lasted until late afternoon.
12th: Sunny start though with a fair bit of cirro cumulus floating around. Feeling very warm.
13th: Sunny start with spotted cirro cumulus. A pleasant day.
14th: Bright start with sunny spells into the morning. Cold wind took edge off sunshine.
15th: Sunny and cool with a cool breeze.
16th: Sunny start but quickly clouded over. Bright spells into the afternoon.
17th: Sunny start but cloud soon filled in. Sunny periods around lunchtime before more cloud arrived.
18th: Cloudy start after recent light rain. Bursts of rain at 11.20am, turning heavy at 12.30pm. Some more rain at midnight.
19th: Cloudy with brief sunny intervals before noon. Then cloudy.
20th: A Cloudy and breezy day. Feeling humid.
21st: Cloudy and breezy through the day though mild. Brief shower at 6pm while driving back from Broadstairs.
22nd: Sunny start though cloud increased during the day to fill in by 2.30pm. Showers, one moderate, from 6pm.
23rd: Sunny start but lots of cloud bubbled up. A lot of threatening cloud to west and east with funnel cloud spotted over Leighton Buzzard. https://twitter.com/Chxrlie_Mxrch/status/734818236211068930 Cleared overnight to leave cold night.
24th: Sunny start quickly clouded over by 11am, then just sunny intervals
25th: Cloudy and cool all day thanks to HP bringing drift off North Sea.
26th: Sunny start with sunny spells though the day
27th: Cloudy start though with sunny spells developing at lunchtime and a clearance around 1pm – 2pm. More convective cloud bubbled up however, to leave a humid evening. Rain developing at 7am.
28th: Cloudy, damp start though with a little brightness at 11am. Some sunny intervals in the afternoon though much cloud.
29th: Cloudy and cool start. Hazy sunny spells in early afternoon, though still much cloud around.
30th: Cloudy with just two sunny intervals that momentarily lifted the temperature. Rain started at 7.30am and was heavy at times up to obs time. Elderly man killed on crossing, possibly due to the bad weather
31st: Rain to start. Outbreaks lasted up until 1315z then stayed cloudy, damp and chilly into the evening and night.