1976 | Wanstead Meteo

June 2017 has been a month of real contrasts. A thundery deluge on the 2nd was followed by conditions typically brought by the European monsoon.

Warm weather followed in the second week before a full-blown heatwave arrived bringing the hottest June spell since 1976.

The mean temperature for the month finished at 18.9C, that’s 2.8C above average. It was the second warmest June in a local record going back to 1797. Though it was only 0.4C cooler than 1976 it was also much wetter than that very dry month.

Though it appeared a wet month, over two-thirds of the recorded rain fell in two episodes.

Sunshine for the month was 202.3hrs, 114% of average.

In terms of the rest of the summer you would be forgiven for thinking that we have already had more than our fair share of good weather. One way of looking at it is to count the number of days the mercury rises above 25C with 10 hrs of sunshine. Since May that has happened on 13 occasions – far higher than anything in the past four years.

It will be interesting to see if July and August, normally the months where we get most of our summery weather are as good as June.

Summary for June 2017

Temperature (°C):

Mean (min+max) 18.9

Mean Minimum 13.8

Mean Maximum 23.9

Minimum 9.9 day 12

Maximum 31.5 day 21

Highest Minimum 21.1 day 21

Lowest Maximum 16.7 day 28

Air frosts 0

Rainfall (mm):

Total for month 71.1 (138.9%)

Wettest day 31.2 day 02

High rain rate 108.4 day 02

Rain days 8

Dry days 22

Wind (mph):

Highest Gust 27.3 day 05

Average Speed 3.5

Wind Run 2550.5 miles

Gale days 1

Pressure (mb):

Maximum 1025.0 day 16

Minimum 984.2 day 05

Total hours of sunshine 202.3

Here follows the full weather diary for June. To view full stats follow this link:http://1drv.ms/1kiTuzv

1st: Sunny with scattered cumulus through the morning, the cloud thicker during the day.
2nd: Cloudy start though brightening up with long sunny spells. Cloud bubbled up and a heavy thunderstorm moved in at 3.15pm and lasted an hour. Sunny again by 6pm.
3rd: Bright start with decreasing cloud.
4th: Sunny start though cloud bubbling up late morning into early afternoon. Cloudy and breezy with a few spots of rain at dusk.
5th: Cloudy and very breezy start. Bright at times.
6th: Rain and very windy to start with gale force 9 in Channel. Rain lasted into the early afternoon before clearing to bright spells. Odd shower overnight but remained blustery with a few trees down. Flowering cherry fell at mum’s at 6.30pm.
7th: Sunny with long sunny spells. An area of rain after dark then overcast through the night.
8th: Cloudy and breezy, a shower at noon and some bright spells at 1pm.
9th: Sunny though breezy with lots of cloud. Spots of rain in the wind.
10th: Sunny and warm start with lots of sunshine. Very breezy.
11h: Sunny and feeling very humid but breezy. Alternating between very warm sunshine and cloud. Very brief few drops of rain at dusk then mostly cloudy night.
12th: Sunny periods throughout the day. Cloudier at times. Clear overnight with warm, sunny start.
13th: Sunny, clear start and feeling warm early.
14th: Sunny most of the day with odd cumulus. Very warm though turning a bit fresher overnight.
15th: Sunny morning though with more cloud than yesterday. A fresh breeze developing.
16th: Sunny with variable cloud. Warm.
17th: Sunny though lots of hazy cumulus.
18th: Sunny though much cloud amid the humidity. Felt airless with only limited breeze. Oppressive overnight.
19th: Sunny with cloud decreasing
20th: Bright start though cloud breaking at 11am to leave clear afternoon with just a couple of cumulus.
21st: Sunny and hot all day with patchy cirrus. Warmest June day since 1976 at Heathrow 33.9C. Warm overnight but more of a breeze. Sunny early.
22nd: Very brief rain shower at obs time then sunny intervals. Cooler but still humid. Very breezy overnight.
23rd: Long sunny spells with hazy cumulus. Although cooler still hot in the sunshine. Cooler overnight and breezy.
24th: Mostly cloudy though bright. A sharp shower in the evening.
25th: Bright though mostly cloudy. A couple of bursts of drizzle but then sunny spells late evening.
26th: Sunny with lots of cirrus, cirrocumlus and a fallstreak hole in the sky. Warm but low humidity.
27th Sunny start though sun becoming scarce. Patchy light rain at 10.30am and thunder then a heavy shower at 3.45pm. Rain in the evening that lasted into the early hours.
28th: Cloudy and very dull at times with very light drizzle. Humid.
29th: Cloudy though bright with some sunny intervals.
30th Sunny though with lots of cloud. Decreasing cloud in the afternoon and a pleasant evening.

Ask a dozen people what they think is a heatwave in this country and you’ll probably get 12 different answers.

The view across to St Paul's Cathedral from Bankside at low tide by Scott Whitehead — The view across to St Paul’s from Bankside at low tide.

The UK press is always keen to tell us that a ‘heatwave is on the way’ – even if it is March and the heatwave in question brings temperatures no greater than the high teens Celsius.

Although in the UK there is no official definition of a heatwave the World Meteorological Organization description is “when the daily maximum temperature on more than five consecutive days exceeds the average maximum temperature by 5 °C, the normal period being 1961-1990”. In other words that March heatwave would see the thermometer peak higher than 15.3C five days in a row. Pleasant enough – but no big deal.

The Met Office, working with the Department of Health, provides a ‘Heat-Health Watch System’ for England which is triggered when a threshold temperature in the South East is 31 °C by day and 16 °C overnight for at least two consecutive days.

I have vague memories of the weeks of sunshine in 1976 but the hot spells that stick in my mind the most are August 1990, when the UK temperature record was set in Cheltenham, Gloucestershire, and August 2003 when an 8-day hot spell saw the all-time UK temperature record broken when 38.5C was reached at Brogdale, near Faversham, Kent.

Last July, when compared with the previous summers, saw some of the best summer weather since 2006. But where does last year compare with the good summers of 2003, 1995, 1990 and 1976? I decided to have a look back at the daily records for this area which stretch back to 1959.

I have drawn up a list of all days back to 1959 that have an average mean daily temperature of 23.5C or higher. This shows that there has been 93 such days. However, to qualify for the Met Office’s Heat-Health Watch System – ie two days like this in a row the list narrows. To make my job easier, I have narrowed the list further to 3 consecutive days where the mean has been 23.5C or higher. Though I loathe really hot weather in my experience I can put up with it for a couple of days. It is only when it gets to the third day of hot, sleepless nights that it starts becoming unbearable.

In terms of intensity and hours of sunshine, 2003 comes out on top. Though many people will argue that 1976 is more impressive -that summer, which comes in second, only produced two spells that satisfy my criteria. The first heatwave saw temperatures soar above 31C for six consecutive days from June 23. The start of the second, on July 3, saw Bjorn Borg win the first of five Wimbledon mens’ titles as he prevailed over Ilie Nastase in 35C heat.

The summer of 1995, which saw my driest-ever August with just 0.7mm of rainfall all month, comes in 3rd, with six days of mean temperatures of 23.5C or higher.

Polo advert for the heatwave that coincided with the Queen Mother's birthday in 1990 — Polo advert for the heatwave that coincided with the Queen Mother’s birthday in 1990

Looking at the data another way, ranking the average total daily mean temperature of each spell, sees 2003 again come out 1st, with August 1990 and July 1983, 2nd and 3rd. Looking back through history it is not really surprising that 2003 comes out on top. While it was hot in London the heatwave across the Channel contributed to the death of over 70,000 people throughout Europe, France being the most affected.

This weekend promises to be very warm and sunny but it will pale into insignificance compared with the hot spells of the past. The mean temperature on Saturday and Sunday is unlikely to exceed 17C.