Tag Archives: East London

Two April heatwaves compared

The stats are in and the average maxima for the past few days’ heatwave is 1C lower than the hot spell in 2011: a positive anomaly of 10.6C over six days.

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Although this year’s spell pipped the previous April high temp by 0.2C, the 2011 spell saw slightly higher temperatures and were recorded in a month that finished 3.3C above average – the average for this April is likely to finish only 2C above average.

April 2011 also saw just 3.3mm of rain recorded. The rainfall so far this month is already at 36.7mm, with more likely before the end of the month.

The spell in 2011 saw 74 hours of sunshine in total while this spell only saw 58 hours.

In terms of this summer it is quite possible that we won’t see a week with higher maximum anomalies or more sunshine than we saw across the southeast this week. To give you any idea of just how anon. warm last week was here is what the equivalent temperatures would be at the end of July, on average the warmest time of the year.

25th 29.8
26th 35.4
27th 39.2 (102.6F)
28th 37.7
29th 32.1
30th 33.3

* The Met Office definition of a heatwave (the same as the WMO) states:  “When the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5 °C, the normal period being 1961-1990”.

 

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The large anomalies of the past few days can be seen on this thermo trace

Repeat of March 24th 2013 only 10C colder

The weather this coming weekend reminds me of a March weekend in 2013 when large parts of the south-east woke up to a covering of snow.

Conditions in Wanstead were very knife-edge, the cover being very slushy. I remember going for a bike ride on that Sunday morning. We left Aldersbrook in sleet, the cover grew thicker as we pedalled into Essex. By the time we reached High Beach near Epping there was 8cm of fresh cover. Conditions on the 2-hour plus ride were inclement to say the least – the temperature didn’t rise above 0C!

This weekend we have a similar set-up, only this time the upper air at 5,000ft is a good 10C colder – no knife-edges this time and, if the streamer gets going, many places should see 10cm of cover. Don’t put away that sledge just yet!

 

Winter 2017/18 forecast review

At the beginning of December the opening par for my forecast for winter read:

The mean temperature for winter 2017/18 is looking average overall with average precipitation. While that doesn’t sound exciting for anyone looking for colder weather and snow I think the figures mask frequent 3 or 4 day-long cold snaps from the Arctic interspersed with milder interludes from Atlantic incursions; typical characteristics of a pattern driven by the troposphere. For anything longer term we have to hope for a warming of the stratosphere, a sudden stratospheric warming over the Arctic, that downwells into the troposphere, reversing the general westerly circulation. We are overdue an ‘SSW’ event but, even if one were to happen, its effects wouldn’t be felt until much later in the winter.

Figures generated using QBO statistics in the run up to December were identical to the outcome of 5C. It is figures generated using ENSO statistics, however, that produced the best results considering December, January and February alone.

It would seem that the winter was most influenced by the ENSO variable up until February when the effects of the SSW were enough to overcome it?results

 

 

The cold spell of February / March 1962

The last week or so has been agony for model watching coldies wishing for a snowy end to winter.

27021962
The Synoptic chart for February 27th which saw 4 inches of snow in Stratford, east London

Solutions have often flip-flopped between a mild and cold outlook. Even this morning at 6 days out the GFS and ECM model temperature outcomes differed by some 20C, a choice between spring and deepest winter!

Sometimes you have to try and second guess what is going to happen by looking at previous patterns from years past.

Yesterday at Philip Eden‘s funeral I spoke to Woodford Green resident Ron Button. He pointed out how much this February reminded him of February 1962, a month that was non-descript for the first three weeks before turning very cold and snowy. Ron, who has kept a meticulous record of the weather ever since his interest was prompted by the severe winter of 1947, produced diaries of 1962 when he was living in Stratford. The entry for 26th / 27th read: “4 inches of snow with drifting”!

The March that followed was the coldest of the 20th century, ranking 10th in my list back to 1797, and 0.3C colder than March 2013. The fact that the monthly sunshine in 1962 was only slightly below average is testament to how cold the source of the air must have been. March 2013 was very dull by comparison!

An entry in London-weather.eu reads that March was colder than any of the previous 3 winter months: “The first three weeks were mostly mild and dry. It was often breezy which resulted in fewer than average night frosts. Frontal systems off the Atlantic passed through the London area, most of them weak though on the 12th, nearly 8mm of rain fell with southwesterly winds gusting to 57 knots. During the last week of the month, it became much colder, and on the 26th snow fell with the temperature not rising above -0.3C all day.”

There was no stratospheric sudden warming that winter and ENSO was neutral.

The winter of 1961/62 ranks only 14th in my list of worst winters, mostly because the core of the cold happened in March which is considered spring in meteorological circles

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march 1962 summary

The Snow Survey of Great Britain also makes interesting reading with these entries for February and March.

feb1962feb19622

march 1962

January 2018: rather mild, wet, dull

January 2017 was a wet month. Just over 64mm of rain was recorded, 121 per cent of average, slightly less than last January.Screen Shot 2018-02-04 at 21.20.29

The monthly mean finished 6.4C, 1.2C above average and the mildest January for four years.

Some 44 hours of sunshine were recorded, 88 per cent of average, the dullest January for six years.

The most notable event was during the early hours of the 18th when the ‘storm with no name’ felled many mature trees across a swathe of England, including a large beech on Blake Hall Road that led to the closure of the road during morning rush hour.

Air frosts: 4. Ground frosts: 12. Snow falling: 1

 

Full stats for January here:http://1drv.ms/1rSfT7Y

Summary for January 2018
Temperature (°C):
Mean (1 minute)  6.5
Mean (min+max)   6.4
Mean Minimum     3.5
Mean Maximum     9.3
Minimum          -2.4 day 29
Maximum          13.5 day 28
Highest Minimum  10.8 day 28
Lowest Maximum   4.1 day 20
Air frosts       4
Rainfall (mm):
Total for month  64.4
Wettest day      15.3 day 02
High rain rate   28.2 day 02
Rain days        19
Dry days         12
Wind (mph):
Highest Gust     45.0 day 02
Average Speed    4.2
Wind Run         3124.8 miles
Gale days        1
Pressure (mb):
Maximum          1031.2 day 29
Minimum          986.4 day 02
Days with snow falling         1
Days with snow lying at 0900   0
Total hours of sunshine        44.1

London Grimness index

The last three months in east London have been sunnier than average – hard to believe as we move into a regime of easterlies that will bring showers and anticyclonic gloom.

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A sunless outlook from the Met Office last December

With no sun and short days  it is no surprise that many are probably already feeling short-changed in the solar stakes.

A blog by XMetman on a ‘grimness index’ got me thinking how London fairs in terms of sunshine, temperature and rain in any given winter season.

Using the same criteria, and assuming that most people welcome sunshine, it can be seen that since the least grim winter of 2007-08, the season, over the past 10 years, has been growing steadily worse.

Screen Shot 2017-12-21 at 21.51.54The grimmest winter, considering statistics back to 1881, was, ironically, the 1978-79 ‘Winter of Discontent’ when, again ironically, ‘Sunny Jim’ Callaghan was in Downing Street as widespread strikes coincided with the coldest winter for 16 years. On looking at the Top 10 of grim winters it is striking how most coincide with depressing world events, the Great War, World War 2 and the Korean War!

grim index

The Tory ‘Crisis? What Crisis?’ campaign was probably my first memory of a general election broadcast.

Wanstead fairs well in London cold rush

Since the early hours of Sunday I’ve been tracking official sites around London to see how Wanstead fairs in terms of retaining cold temperatures and snow.

temp trace

The results, comparing hourly obs over 62 hours, show that Wanstead was a degree cooler than St James’s Park, half a degree cooler than Heathrow and marginally cooler than Northholt. Only Kenley, with its whopping 170m of altitude, was cooler.

While half a degree doesn’t sound much it can make all the difference, as we saw at the weekend when some areas recorded inches of snow while others barely a centimetre.

Though the snow has pretty much vanished now it was evident yesterday that the area was far more wintry neighbouring Forest Gate, Leyton and Stratford which had pretty much lost all their cover.

A report on the snow event can be found here.

* For anyone who has a fascination for the weather and whether their back garden in the Counties Estate is colder than their mate’s in the Warren Estate I notice that weather stations are now even cheaper and you don’t need to connect to the net via a dedicated PC. A unit from Ventus (the W830) allows you to connect to the amateur weather network Wunderground. The internet dealer Weatherspares has them on offer. (NB. I am not on commission but would be happy to offer anyone advice who wants to buy and set one up.)

wanstead
Wanstead, Aldersbrook, the Flats and Wanstead Park are all part of a ‘green island’ in east London that tends to hold the cold better than surrounding built up areas

Dreaming of a white Christmas?

I’m not. And it is not because a glimpse at the latest GFS operational run at T+324z (on the 12th) reveals that many could be sitting down to their festive lunch in mild Atlantic air, with possible frontal rain bringing a miserable afternoon with heavy rain in the evening.

Cold spells in early to mid December often end around the 20th, a momentary change to a more mobile regime. Even the cold winter of 1962/63 saw this mid-December warm up with the snow not arriving until Boxing Day.

I will be keeping a daily eye on the GFS and adding to this blog to watch the daily twists and turns, adding to this blog from here.

Just over 24hrs away now on Sunday 24th and the weather tomorrow is again looking mild,in London, about 11C and breezy at lunchtime with rain spreading in very late evening. Best chance of any flakes over the high ground of Scotland.

Screen Shot 2017-12-24 at 08.00.37

On Saturday 23rd, just 54hrs away now, and the GFS op run is again showing the same change to cooler air albeit slightly delayed to previous runs. Temps in London about 10C / 11C, breezy – any rain not arriving to well into the evening. Best chance of any UK snow is Glasgow, into the evening as the cold front clears – and obviously flakes on high ground in the north.

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On Friday 22nd, less than 90hrs away, the GFS is again showing the UK on the cusp of a change. Conditions in London look very mild 11C – 13C before dropping back to 5C after a spell of rain in the evening. Best chance of any snow over the highest points of Scotland.

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Down to 108hrs to lunchtime on the 25th and the situation still shows the weather regime on the cusp of change with the anticyclone over France pulling away south. High temps in London about 9C or 10C with rain late in the evening. Snow risk across the Highlands as colder air digs in. Screen Shot 2017-12-21 at 08.35.34

On Wedesday 20th, the synoptic situation on 25th looks on the cusp of a big change to something more unsettled as the high pulls well south of its current position. A heavy band of rain is approaching from the west though it would be well into the evening before it affects London. Best chance of any snowfall if you fancy a flutter is Glasgow.

Screen Shot 2017-12-20 at 09.23.28

On Tuesday 19th, Christmas lunchtime appears to be the transition day from the present high pressure dominated weather to something cyclonic. In London a dry, cool and cloudy start will be quickly replaced by a spell of rain that clears eastwards. Max 11C, min 3C as the front clears. Best chance of snow looks west coast of Scotland and Pennines.Screen Shot 2017-12-19 at 08.28.58

A week from today and Christmas day will have already dawned. The GFS 00z op presents an unsettled outlook with a transition from mild to cold; London looks warmest at 9am before a cold front sweeps SE’wards. Best chance of anything wintry falling: west coast of Scotlands and Pennines. Over the last couple of years the pattern has already been locked in to mild but this year’s constant ups and downs suggests the weather type  it is all still to play for. Screen Shot 2017-12-18 at 08.13.28

On Sunday 17th, the weather is looking less settled than yesterday with a weak high pressure much further south over the Pyrenees. A cool NW’ly regime with upper air around -5C, allowing any precipitation to be wintry. A chance of snow west coast of Scotland, Pennines and north-west Wales.

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On Saturday 16th, weather on the 25th is under the influence of high pressure centred over Brittany. Quiet weather with a high of 6C or 7C after an overnight frost. There appears little chance of anything wintry falling as the source of the upper air is all the way from the Azores.

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On Friday 15th, Christmas day lunchtime again looks like a day in between a relatively settled mild pattern and a cold, unsettled regime with potential for slider lows after Boxing Day. The 25th itself again looks chilly and nondescript. A high of 6C or 7C, light winds and potential for some rain later. Things are in a state of flux so I’d expect detail to change again tomorrow.

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On Thursday 14th, midday on 25th is looking fairly non-descript. High pressure sits over the near continent with a declining ridge up to Scotland; the UK sits in a battleground with cold air over the near continent and mild air trying to push in from the Atlantic – most of the UK is just on the chilly side. The best chance of any snow is the east coast of Scotland. Still all to play for but it was this date over the past couple of years that the models started to get a good handle on Christmas day proceedings.Screen Shot 2017-12-14 at 14.35.19

Screen Shot 2017-12-13 at 09.52.12On Wednesday 13th I notice that the Daily Star reckon we are ‘odds on’ for a white Christmas, yet I can’t find a bookie anywhere to ‘lay’ these odds; at 12 days out there’s no way any model could be ‘odds on’.

This morning’s (12th) 00Z operational run of the GFS has London at 10C with a chance of rain. Best chance of any white stuff probably Aberdeen.

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November 2017: below average, dry

November 2017 was another dry month. Just over 33mm of rain was recorded, the driest November since 2011 and the 40th driest since 1797.Screen Shot 2017-12-02 at 17.23.28

The monthly mean finished 7.1C, 1C below average and only the fourth cooler than average month this year.

Some 71 hours of sunshine were recorded, 122 per cent of average – the sunniest November since 2007.

Air frosts: 6, Ground frosts: 17, snow falling: 1 (just a few flakes on the 30th, the first November snow in years.)

The start of December looks like it start mainly dry, an anticyclone over the Atlantic that has brought respite from last week’s cold weather will pull away into the continent to be replaced by low pressure. This depression will track across northern England gradually pulling cold, Polar air across the UK on Thursday.

The models go against what has followed dry Novembers in the past – patterns overwhelmingly suggest that December will be average to rather mild and on the dry side. Winter is looking average overall.

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

Summary for November 2017
Temperature (°C):
Mean (1 minute)  7.4
Mean (min+max)   7.1
Mean Minimum     3.5
Mean Maximum     10.6
Minimum          -2.7 day 24
Maximum          15.5 day 22
Highest Minimum  12.3 day 21
Lowest Maximum   3.7 day 30
Air frosts       6
Rainfall (mm):
Total for month  33.3
Wettest day      8.5 day 10
High rain rate   12.1 day 22
Rain days        14
Dry days         16
Wind (mph):
Highest Gust     22.1 day 23
Average Speed    2.7
Wind Run         1952.8 miles
Gale days        0
Pressure (mb):
Maximum          1029.6 day 17
Minimum          985.2 day 22
Days with snow falling         1
Days with snow lying at 0900   0
Total hours of sunshine        71.2
Screen Shot 2017-12-02 at 17.24.28

October 2017: warm, very dry and dull

October 2017 was a very dry month. Just 12.6mm of rain were recorded, the driest October since 1995 and the 11th driest since 1797.

The monthly mean finished 13.1C, 1.3C above average and the seventh warmer than average month this year.

Some 81 hours of sunshine were recorded, 76 per cent of average – the 4th duller than average month in a row. Just three months have been sunnier than normal in 2017!

Air frosts: 0, Ground frosts: 2

The first half of November looks like it will be predominantly anticyclonic. Expect lots of calm weather with the usual frost and fog.

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

Summary for October 2017
Temperature (°C):
Mean (1 minute)  13.2
Mean (min+max)   13.1
Mean Minimum     9.7
Mean Maximum     16.6
Minimum          0.9 day 29
Maximum          22.2 day 16
Highest Minimum  15.8 day 13
Lowest Maximum   11.3 day 30
Air frosts       0
Rainfall (mm):
Total for month  12.6
Wettest day      2.8 day 18
High rain rate   12.1 day 11
Rain days        8
Dry days         23
Wind (mph):
Highest Gust     23.5 day 02
Average Speed    3.4
Wind Run         2495.1 miles
Gale days        0
Pressure (mb):
Maximum          1034.0 day 27
Minimum          996.3 day 19
Days with snow falling         0
Days with snow lying at 0900   0
Total hours of sunshine        0.0