Tag Archives: wanstead

Wanstead and the UK’s top 10 hottest days

Britain’s capital is often the location of the UK’s hottest weather but a look back to 1911 shows it is often elsewhere the mercury is highest.

The highest temperature record has been broken three times in my lifetime. Before the first occasion in August 1990 you’d often see press articles speculating: “Will the UK ever break 100 Fahrenheit?

Polo advert for the heatwave that coincided with the Queen Mother’s 90th birthday in 1990

Though 100F was recorded at Greenwich in August 1911 the station’s use of a Glaisher stand (an instrument that depends on the observer turning it away from direct sunlight throughout the day) the record was deemed unsafe and a temperature of 36.7C at Raunds, Northants, was established as the new record.

The record stood for nearly 80 years before it was eclipsed, 37.1C being measured at Chelteham.

Thirteen years later the record was broken again, this time Brogdale, near Faversham, registering 38.5C.

Sixteen years on Cambridge became the UK’s hottest place, recording 38.7C. Just three years later the UK recorded >40C for the first time, a record of 40.3C at Coningsby, Lincs.

The table below shows how Wanstead and stations around London faired on each day.

Of note is how much cooler this area is when the core of the heat is at Wisley. The 10th hottest day on July 19th 2006 saw 36.5C recorded at the RHS garden, but Wanstead was nearly 3C cooler.

Today (23/06/2026) Wisley recorded 34.6C yet Wanstead, at 31.9C, was again nearly 3C cooler.

Hours of thunder on June 23, 2026

I noticed the first drops of rain from this event riding back over Wanstead Flats from the Holly Tree around 10pm, thoughts of Messi’s majesty in Argentina’s win against Austria fast being replaced by watching clouds bubbling overhead.

Reaching home the drops didn’t come to much and I wondered if the action would miss us, like so many damp squibs in the past.

Nevertheless, I closed the roof windows and sure enough the first heavy rain arrived at 0130. And rumbled on and off for another four hours. It reminded me of the overnight storms that were so common in the 1980s.

Some 36.8mm fell, the greatest June downpour at this station for 10 years. This month’s rainfall total now stands at 93mm, 181% of average, the wettest June for 10 years and 7th wettest back to 1960.

It feels strange that the storm happened 10 years almost to the minute of the Brexit deluge of 2016.

Radar from the storm can be found at this link.

The Brexit deluge, 10 years on

It’s 10 years tonight that this station recorded over 60mm of rain in 24 hours.

It remains the largest daily fall at this station since records began in 1960.

Rainfall rates touched over 60mm/hr during the early hours of June 23rd.

The closest station at the waterworks at Redbridge Roundabout recorded a similar amount.

The next closest official station, St James’s Park, recorded only 46mm, illustrating how varied rainfall can be over a small area.

The rainfall during the event was around three times heavier than the deluge on June 2nd.

Hours of frost

The opening week or so of 2026 has already seen 30 per cent of frost hours recorded locally in an average year.

The temperature at the site in Wanstead has been -0.1C or lower for nearly 64 hours, already more than half of what was recorded here in the whole of 2020.

The mean for January is currently 1.1C, 4.1C below average. It’s also been a wet start with 28mm of rain, 53 per cent of the whole month average.

While there’s been colder starts to a year continuous data that allows this kind of analysis only stretches back to 2014 on this site.

A remarkable sunny spell

Sunshine of late seems to have been endless with the past 10 days being virtually cloudless from dawn to dusk.

After a very sunny March which saw over 170% of average sunshine recorded at Heathrow April has already seen over 56% of average sun hours in the first eight days.

In terms of the total percentage possible of sun hours the past 11 days are second only to a period in 1990 that stretched from April 27th until May 7th.

The pattern has seen an anticyclone near stationary to our north, generating a dry NE’ly feed. Some 12.2 hours of sunshine were recorded at Heathrow on the 6th.

London winter forecast 2024/25

The coming winter is likely to be mild and wet overall thanks to a predominant south-westerly Atlantic regime.

While that may sound grim for any snow and cold lovers reading this I would suggest that the possibility of brief cold snaps this season are higher than they have been during the last few winters.

This year I have tried to improve my statistical method by adding warming on to previous years to, hopefully, give better results.

In terms of rainfall and mean temperature a total of eleven years were similar to this October and November, spanning 1826 to 2021.

The probabilities for the following DJF winter were thus.

Mean temperatureProbabilityRainfallProbability
Very mild46%Wet33%
Average to mild33%Average37%
Below average21%Dry30%

London winter forecast 2024/25

Looking deeper into the stats I had a look at the Oceanic Niño Index; no years were similar to this one though the index only goes as far back as 1950 – so no real help.

The prognosis for snow at this point seems bleak – though chances may be heightened should we experience a stratospheric sudden warming in December / January. Though, as seen in 1987 where a vortex ‘split’ was recorded, this would still not guarantee wintry weather.

Looking at the data month to month would suggest the best chance of a cold snap around December 22nd through Christmas before warming up in the New Year. Beyond that I would suggest that the chances of another cold snap in January are higher than they have been for the last few winters. February, however, looks very mild and possibly very wet.

Best I can do – have a good winter all!

Below is how I think each month will unfold.

Dec mean temperatureProbabilityRainfallProbability
Very mild64%Wet27%
Average to mild27%Average46%
Below average9%Dry27%
Jan mean temperatureProbabilityRainfallProbability
Very mild10%Wet17%
Average to mild45%Average28%
Below average45%Dry55%
Feb mean temperatureProbabilityRainfallProbability
Very mild64%Wet55%
Average to mild28%Average36%
Below average8%Dry9%

Chance of a surprise white Christmas

It’s been an unusual autumn so far. A very notable lack of sun from the end of October into November was followed by an early cold snap before Storm Bert brought flooding chaos to parts of south Wales, the West Country and elsewhere.

Just before the beginning of every winter I have a crack at predicting what winter will be like; the results often being very mixed.

However, on looking at the stats so far there’s virtually no years that have been similar to this autumn; the one year being 1968.

1968, looking back at reanalyis charts, swung from mild to cold with snow on Christmas Day. The Weather Outlook mentions the conditions on the 25th.

Though the odds are very long at this stage the 850mb chart for 1968 is not beyond the realms of possibilities given the recent synoptic patterns. And if not the 25th I would suggest that a cold snap between Christmas and New Year is a better chance than evens this year.

1968 was the year Bing Crosby sung an alternative intro to White Christmas while marooned in a sunny California.

The sun is shining, the grass is green;
the orange and palm trees sway.
There’s never been such a day
in Beverly Hills, LA.
But it’s December 24th ,
and I long to be up north!

Though we think of snow at Christmas in London it is very rare. And has often been rare been since Victorian times.

Years of anomalous warmth

Today marks the 866th consecutive day that the rolling 365-day mean has been above 12C, a level that is nearly a degree above the average annual mean temperature for this region.

The next longest period, back to 1960, was 499 days starting on June 9th 2003.

The graph below shows that since around 2015 this 23,644 day period has been stuck in a high rut.

Looking at months on their own it has now been over 20 since this station recorded a month around a degree cooler than average.

The monthly mean temperature anomalies considering 1981-2010 averages.

This September is looking like it will be yet another milder than average month. If the mean for 2024 finishes above the level of 12C it will be the third 12C year in a row!

Prior to this an annual mean of 12C has been recorded on only 11 occasions since 1960: 1989, 1997, 1999, 2002, 2003, 2011, 2014, 2018, 2020, 2022, 2023 .

September thunderstorms

This September has seen a lot of convective activity with three days of thunder, already more than the whole of meteorological summer.

The first storms arrived during the early hours of the 8th. Lots of thunder and lightning though only 7.1mm of rain. Further storms bubbled up at 1200 and 1720 with 9.8mm of rain.

Both the 11th and 12th have seen further thunderstorms develop with hail recorded though rain amounts were low; with 0.4mm and 0.6mm recorded respectively.

Here’s a timelapse of cloud activity on the 8th.

July 2024 in Wanstead

The mean for July in east London was 18.4C, 0.1C below the 1981-2010 average and the coolest for 12 years.

Rainfall of 67.1mm was 154% of average, 3mm less than last July. Sunshine at 177.3 hours was 92% of average. Duller than average but not as dull as last July.

A largely uneventful month with an absence of thunder and lightning.

As thought months ago with ENSO moving toward neutral August should be the month with the best chance of any heat records being broken.

A look at the mean temperature shows how much the climate has warmed since the period 1961-90. Though the mean last month was 1.3C down on the previous 10 years it was actually 0.7C warmer than 1961-90.

9am air pressure was largely below average until the final third of the month, coinciding with the arrival of more summer-like weather.

Here’s a few extremes for the month of August across the capital.