Weather in South London during June 2009
Rather dry with above average temperatures.
Temperatures
The average maximum temperature was 21.8 Celsius (72F), and that was 0.9 degree Celsius (1.6F) above the 20-year normal. The average minimum temperature was 11.6 Celsius (53F), and that was 0.2 Celsius (0.3F) above normal.
The highest temperature recorded during June was 29.7 Celsius (85F), on the 29th, but the 30th was only 0.1 Celsius cooler. The temperature exceeded 25 Celsius (77F) on 6 occasions during June. The last week produced 5 of the very warm days, but the temperature also rose above 25 Celsius on the 2nd. On 12 days, the maxima were below 20 Celsius (68F). The coolest period was from the 3rd to the 10th, with only 3 rather cool days occurring after mid month. The maximum temperature on the 5th was only 14.3 Celsius (58F), and this was the coolest June day for 7 years.
The minimum temperature on the night of the 29th/30th was 16.4 Celsius (61F), but there were only 3 other nights with minima above 14 Celsius (57F) with all of these occurring during the last week. There were 5 nights when the temperature fell below 10 Celsius (50F) with all of these occurring during the first fortnight of June. On the night of the 11th/12th the temperature dipped to 5.8 Celsius (42F) but the night of the 3rd/4th was only 0.2 Celsius milder.,
Frost
There were no air or grass frosts during June. A grass minimum of 1.0 celsius (34F) occurred on the night of the 11th/12th with 1.7 Celsius the reading on the morning of the 4th.
Rain
A total of 33.4 millimetres (1.3ins) of rain fell during June, and that was over 30% below the long-term average. Measurable rain fell on 12 days, 1 day above average, but with the 5 wet days (1.0mm/0.04 ins, or more) 3 days below average. The wettest spell occurred towards the end of the first week through to the middle of the second week. This accounted for nearly 27 millimetres (1.06 ins), and included 13.4 millimetres (0.5 ins) that was measured on the 6th. After mid month, only 1.5 millimettres (0.06ins) of rain was recorded.
Thunderstorms
There were 3 days with thunder during June. On the 7th, it was particularly noisy between 0517 and 0611 UTC. with further thunder at 1913. On the 15th there were thunderstorms from late afternoon, these lasting, almost without breaks, until mid evening. The final storm of the month only produced a few spots of rain but rumbledon from 1537 until 1731 UTC.
Hail
Small hail was observed in a shower during the early evening of the 7th.
Snow
None reported.
Wind
Winds were generally gentle. Mainly from between northeast and southeast at either end of the month, and from between northwest and southwest during the 2nd, 3rd and 4th weeks. The maximum gust only exceeded 20 knots (23mph) on 5 days during June, but on the 17th a gust of 30 knots (34mph) occurred.
Fog
None reported in this part of London.
Monthly figures for June in, and around, London
The average maximum temperature was 21.8 Celsius (72F), and that was 0.9 degree Celsius (1.6F) above the 20-year normal. The average minimum temperature was 11.6 Celsius (53F), and that was 0.2 Celsius (0.3F) above normal.
The highest temperature recorded during June was 29.7 Celsius (85F), on the 29th, but the 30th was only 0.1 Celsius cooler. The temperature exceeded 25 Celsius (77F) on 6 occasions during June. The last week produced 5 of the very warm days, but the temperature also rose above 25 Celsius on the 2nd. On 12 days, the maxima were below 20 Celsius (68F). The coolest period was from the 3rd to the 10th, with only 3 rather cool days occurring after mid month. The maximum temperature on the 5th was only 14.3 Celsius (58F), and this was the coolest June day for 7 years.
The minimum temperature on the night of the 29th/30th was 16.4 Celsius (61F), but there were only 3 other nights with minima above 14 Celsius (57F) with all of these occurring during the last week. There were 5 nights when the temperature fell below 10 Celsius (50F) with all of these occurring during the first fortnight of June. On the night of the 11th/12th the temperature dipped to 5.8 Celsius (42F) but the night of the 3rd/4th was only 0.2 Celsius milder.,
Frost
There were no air or grass frosts during June. A grass minimum of 1.0 celsius (34F) occurred on the night of the 11th/12th with 1.7 Celsius the reading on the morning of the 4th.
Rain
A total of 33.4 millimetres (1.3ins) of rain fell during June, and that was over 30% below the long-term average. Measurable rain fell on 12 days, 1 day above average, but with the 5 wet days (1.0mm/0.04 ins, or more) 3 days below average. The wettest spell occurred towards the end of the first week through to the middle of the second week. This accounted for nearly 27 millimetres (1.06 ins), and included 13.4 millimetres (0.5 ins) that was measured on the 6th. After mid month, only 1.5 millimettres (0.06ins) of rain was recorded.
Thunderstorms
There were 3 days with thunder during June. On the 7th, it was particularly noisy between 0517 and 0611 UTC. with further thunder at 1913. On the 15th there were thunderstorms from late afternoon, these lasting, almost without breaks, until mid evening. The final storm of the month only produced a few spots of rain but rumbledon from 1537 until 1731 UTC.
Hail
Small hail was observed in a shower during the early evening of the 7th.
Snow
None reported.
Wind
Winds were generally gentle. Mainly from between northeast and southeast at either end of the month, and from between northwest and southwest during the 2nd, 3rd and 4th weeks. The maximum gust only exceeded 20 knots (23mph) on 5 days during June, but on the 17th a gust of 30 knots (34mph) occurred.
Fog
None reported in this part of London.
Monthly figures for June in, and around, London
| Place | Maximum | Minimum | Rainfall (mm) |
| C. London | 30.7 | 8.6 | 33 |
| Heathrow A/P | 30.8 | 7.8 | 35 |
| Gatwick A/P | 30.4 | 4.1 | 20 |
| Croydon | 27.8 | 4.2 | 31 |
| Northolt | 29.5 | 5.7 | 54 |
| Farnborough | 29.2 | 3.0 | 22 |
| Stansted A/P | 27.3 | 5.2 | 22 |