Climate and monthly weather forecastHarmondsworth, United Kingdom
Climate and monthly weather forecast
Weather in January
January, the same as December, in Harmondsworth, United Kingdom, is a frosty winter month, with an average temperature varying between 1.9°C (35.4°F) and 6.8°C (44.2°F). January is the coldest month, with an average high-temperature of 6.8°C (44.2°F) and an average low-temperature of 1.9°C (35.4°F). Weather in January »Weather in February
February, the last month of the winter in Harmondsworth, is another chilly month, with temperature in the range of an average high of 7.6°C (45.7°F) and an average low of 2.5°C (36.5°F). February denotes a minimal variation in the average high-temperature to a still frosty 7.6°C (45.7°F) from January's 6.8°C (44.2°F). Weather in February »Weather in March
The first month of the spring, March, is a cool month in Harmondsworth, United Kingdom, with an average temperature ranging between max 10.5°C (50.9°F) and min 3.4°C (38.1°F). Harmondsworth's shift from February to March is accompanied by an average high-temperature of a fresh 10.5°C (50.9°F), a slight deviation from 7.6°C (45.7°F). Weather in March »Weather in April
April is a mild spring month in Harmondsworth, United Kingdom, with temperature in the range of an average low of 5.3°C (41.5°F) and an average high of 14.3°C (57.7°F). With the onset of April, Harmondsworth's average high-temperature experiences a slight rise, moving from March's cool 10.5°C (50.9°F) to a refreshing 14.3°C (57.7°F). Weather in April »Weather in May
The last month of the spring, May, is a comfortable month in Harmondsworth, United Kingdom, with an average temperature varying between 7.9°C (46.2°F) and 16.8°C (62.2°F). The transition into May reveals an average high-temperature of a comfortable 16.8°C (62.2°F), mirroring a close resemblance to April. Weather in May »Weather in June
The first month of the summer, June, is still a comfortable month in Harmondsworth, United Kingdom, with an average temperature ranging between max 19.7°C (67.5°F) and min 10.8°C (51.4°F). June's climate shows a minor adjustment in average high-temperatures to a still comfortable 19.7°C (67.5°F) from May's 16.8°C (62.2°F). Weather in June »Weather in July
July in Harmondsworth, United Kingdom, is an agreeable summer month, with an average temperature ranging between max 22°C (71.6°F) and min 13.2°C (55.8°F). July is the month when Harmondsworth, United Kingdom, sees the highest average temperatures, with a high of 22°C (71.6°F) and a low of 13.2°C (55.8°F). Weather in July »Weather in August
The last month of the summer, August, is also an agreeable month in Harmondsworth, United Kingdom, with an average temperature fluctuating between 13.7°C (56.7°F) and 21.6°C (70.9°F). As August takes hold, the average high-temperature is a still agreeable 21.6°C (70.9°F), nearly mirroring that of the previous month. Weather in August »Weather in September
The first month of the autumn, September, is also an enjoyable month in Harmondsworth, United Kingdom, with an average temperature fluctuating between 11°C (51.8°F) and 18.8°C (65.8°F). Harmondsworth's weather, upon September's arrival, documents an average high-temperature of a refreshing 18.8°C (65.8°F), nearly identical to the prior month. Weather in September »Weather in October
October, the same as September, in Harmondsworth, United Kingdom, is a moderate autumn month, with temperature in the range of an average high of 15.1°C (59.2°F) and an average low of 8.9°C (48°F). October is marked by a subtle drop in average high-temperatures, transitioning from an enjoyable 18.8°C (65.8°F) in September to a moderate 15.1°C (59.2°F). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Harmondsworth, United Kingdom, with an average temperature ranging between min 5.6°C (42.1°F) and max 10.2°C (50.4°F). The start of November comes with a small reduction in the average high-temperature, subtly receding from a mild 15.1°C (59.2°F) in October to a cool 10.2°C (50.4°F). Weather in November »Weather in December
December, the first month of the winter in Harmondsworth, is also a frosty month, with an average temperature ranging between max 7.9°C (46.2°F) and min 3.4°C (38.1°F). With December's arrival, Harmondsworth notes an average high-temperature of a chilly 7.9°C (46.2°F), closely following the trend of the preceding month. Weather in December »Updated: Feb 7, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Harmondsworth's January weather, marked by an average high temperature of 6.8°C (44.2°F) and an average low temperature of 1.9°C (35.4°F), is the coldest in the year.
January, March through May are months with the least rain in Harmondsworth, United Kingdom, when the rain falls for 6.8 days and typically aggregates up to 9mm (0.35") of rain.
Throughout the year, there are 109 rainfall days, and 156mm (6.14") of precipitation is accumulated.
January through March and December are months with snowfall in Harmondsworth, United Kingdom.
The months with the most snowfall are January and February, with an average 6mm (0.24") of accumulated snow.
In Harmondsworth, during the entire year, snow falls for 5.6 days and aggregates up to 18mm (0.71") of snow.
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
The month with the least sunshine in Harmondsworth is February, with an average of 3.7h of sunshine.
In Harmondsworth, United Kingdom, snow does not fall in April through November.
The month with the most rainfall is June, when the rain falls for 12.3 days and typically aggregates up to 21mm (0.83") of precipitation.
June has the longest days of the year in Harmondsworth, with an average of 16h and 36min of daylight.
The months with the highest UV index are June and July, with an average maximum UV index of 5.
In Harmondsworth, temperatures reach their average annual highs in July, measuring 22°C (71.6°F) and a minimum average of 13.2°C (55.8°F).
July and August, with an average relative humidity of 74%, are the least humid months in Harmondsworth.
With an average of 7.9h of sunshine, July has the most sunshine of the year in Harmondsworth, United Kingdom.
On Sunday, 27. October 2024, at 2:00 am, Daylight Saving Time ends in Harmondsworth, and the time zone changes from BST to GMT. The next Daylight Saving Time starts on Sunday, 30. March 2025, at 1:00 am, and the time zone reverts from GMT to BST.
December is the most humid month, with an average relative humidity of 89%.
December has the shortest days of the year in Harmondsworth, with an average of 7h and 54min of daylight.
Average temperature
Harmondsworth, United Kingdom
The warmest month (with the highest average high temperature) is July (22°C).
The month with the lowest average high temperature is January (6.8°C).
The month with the highest average low temperature is August (13.7°C).
The coldest month (with the lowest average low temperature) is January (1.9°C).
Average pressure
Harmondsworth, United Kingdom
- Average pressure in January:
1014.5mbar - Average pressure in February:
1013.8mbar - Average pressure in March:
1015.5mbar - Average pressure in April:
1015.7mbar - Average pressure in May:
1016.8mbar - Average pressure in June:
1016.2mbar
- Average pressure in July:
1015.4mbar - Average pressure in August:
1014.9mbar - Average pressure in September:
1016.9mbar - Average pressure in October:
1015.1mbar - Average pressure in November:
1010.5mbar - Average pressure in December:
1014.5mbar
The month with the highest atmospheric pressure is September (1016.9mbar).
The month with the lowest atmospheric pressure is November (1010.5mbar).
Average wind speed
Harmondsworth, United Kingdom
- Average wind speed in January:
16.6km/h - Average wind speed in February:
17.5km/h - Average wind speed in March:
16km/h - Average wind speed in April:
13.4km/h - Average wind speed in May:
13.4km/h - Average wind speed in June:
13km/h
- Average wind speed in July:
12.7km/h - Average wind speed in August:
12.8km/h - Average wind speed in September:
12.7km/h - Average wind speed in October:
14.5km/h - Average wind speed in November:
15.7km/h - Average wind speed in December:
17.1km/h
The windiest month (with the highest average wind speed) is February (17.5km/h).
The calmest months (with the lowest average wind speed) are July and September (12.7km/h).
Average humidity
Harmondsworth, United Kingdom
The month with the highest relative humidity is December (89%).
The months with the lowest relative humidity are July and August (74%).
Average rainfall
Harmondsworth, United Kingdom
The wettest month (with the highest rainfall) is June (21mm).
The driest months (with the least rainfall) are January, March, April and May (9mm).
Average rainfall days
Harmondsworth, United Kingdom
- Average rainfall days in January:
6.8 days - Average rainfall days in February:
7.5 days - Average rainfall days in March:
8.4 days - Average rainfall days in April:
10.3 days - Average rainfall days in May:
9.8 days - Average rainfall days in June:
12.3 days
- Average rainfall days in July:
12 days - Average rainfall days in August:
10.9 days - Average rainfall days in September:
7 days - Average rainfall days in October:
7.3 days - Average rainfall days in November:
8.5 days - Average rainfall days in December:
8.2 days
The month with the highest number of rainy days is June (12.3 days).
The month with the least rainy days is January (6.8 days).
Average snowfall
Harmondsworth, United Kingdom
The months with the highest snowfall are January and February (6mm).
The months with the least snowfall are April, May, June, July, August, September, October and November (0mm).
Average snowfall days
Harmondsworth, United Kingdom
- Average snowfall days in January:
1.5 days - Average snowfall days in February:
2 days - Average snowfall days in March:
0.5 days - Average snowfall days in April:
0.2 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0 days - Average snowfall days in November:
0.3 days - Average snowfall days in December:
1.1 days
The month with the highest number of snowfall days is February (2 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Harmondsworth, United Kingdom
- Average daylight in January:
8h and 30min - Average daylight in February:
10h and 0min - Average daylight in March:
11h and 54min - Average daylight in April:
13h and 54min - Average daylight in May:
15h and 36min - Average daylight in June:
16h and 36min
- Average daylight in July:
16h and 6min - Average daylight in August:
14h and 36min - Average daylight in September:
12h and 36min - Average daylight in October:
10h and 42min - Average daylight in November:
8h and 54min - Average daylight in December:
7h and 54min
The month with the longest days is June (Average daylight: 16h and 36min).
The month with the shortest days is December (Average daylight: 7h and 54min).
- Average sunshine in January:
4h and 12min - Average sunshine in February:
3h and 42min - Average sunshine in March:
5h and 30min - Average sunshine in April:
7h and 36min - Average sunshine in May:
7h and 30min - Average sunshine in June:
7h and 30min
- Average sunshine in July:
7h and 54min - Average sunshine in August:
7h and 48min - Average sunshine in September:
7h and 6min - Average sunshine in October:
4h and 30min - Average sunshine in November:
4h and 0min - Average sunshine in December:
4h and 18min
The month with the most sunshine is July (Average sunshine: 7h and 54min).
The month with the least sunshine is February (Average sunshine: 3h and 42min).
Average sunshine days
Harmondsworth, United Kingdom
- Average sunshine days in January:
20.1 days - Average sunshine days in February:
16.5 days - Average sunshine days in March:
20 days - Average sunshine days in April:
16.3 days - Average sunshine days in May:
16.7 days - Average sunshine days in June:
14.2 days
- Average sunshine days in July:
14.2 days - Average sunshine days in August:
14.8 days - Average sunshine days in September:
19.8 days - Average sunshine days in October:
20.2 days - Average sunshine days in November:
18.1 days - Average sunshine days in December:
19.8 days
The month with the most sunshine days is October (20.2 days).
The months with the least sunshine days are June and July (14.2 days).
Average UV index
Harmondsworth, United Kingdom
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
Harmondsworth, United Kingdom
The month with the most cloud cover is February (Cloud cover 61).
The month with the least cloud cover is April (Cloud cover 49).
Average visibility
Harmondsworth, United Kingdom
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October and December (9km).
The month with the lowest visibility is November (8km).
