Harmondsworth weather

The Harmondsworth weather guide shows monthly weather averages (including daytime and night-time temperatures, rainfall and hours of sunshine) for holidays in Harmondsworth, Greater London, England in 2026/2027.

• Harmondsworth weather averages
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Harmondsworth weather averages

Check the Harmondsworth weather averages for each month of the year including maximum daytime and minimum night-time temperatures, monthly rainfall, number of days with rain and average daily hours of sunshine for Harmondsworth, Greater London, England.

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Harmondsworth weather by month

Check the weather for Harmondsworth, Greater London, England for a particular month by selecting from the list below. This gives the best indication of what to expect from the weather months in advance.

• January
• February
• March
• April
• May
• June
• July
• August
• September
• October
• November
• December

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Harmondsworth weather in January

The average maximum daytime temperature in Harmondsworth in January is a cold 7°C (45°F), while the average minimum night-time temperature is a cold 1°C (34°F). You can expect on average 2 hours of sunshine a day in Harmondsworth during January.

• 7
  7°C max day temperature
• 2
  2 hours of sunshine per day
• 16
  16 days with some rainfall
• 1
  1°C min night temperature
• 80
  80 mm of monthly rainfall

On average 80 mm (3.1 inches) of rain normally falls in Harmondsworth during January with rain falling on 16 days of the month.

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Harmondsworth weather in February

The average maximum daytime temperature in Harmondsworth in February is a cold 7°C (45°F), while the average minimum night-time temperature is a cold 1°C (34°F). You can expect on average 2 hours of sunshine a day in Harmondsworth during February.

• 7
  7°C max day temperature
• 2
  2 hours of sunshine per day
• 13
  13 days with some rainfall
• 1
  1°C min night temperature
• 50
  50 mm of monthly rainfall

On average 50 mm (2 inches) of rain normally falls in Harmondsworth during February with rain falling on 13 days of the month.

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Harmondsworth weather in March

The average maximum daytime temperature in Harmondsworth in March is a cool 10°C (50°F), while the average minimum night-time temperature is a cold 2°C (36°F). You can expect on average 4 hours of sunshine a day in Harmondsworth during March.

• 10
  10°C max day temperature
• 4
  4 hours of sunshine per day
• 15
  15 days with some rainfall
• 2
  2°C min night temperature
• 58
  58 mm of monthly rainfall

On average 58 mm (2.3 inches) of rain normally falls in Harmondsworth during March with rain falling on 15 days of the month.

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Harmondsworth weather in April

The average maximum daytime temperature in Harmondsworth in April is a cool 12°C (54°F), while the average minimum night-time temperature is a cold 4°C (39°F). You can expect on average 5 hours of sunshine a day in Harmondsworth during April.

• 12
  12°C max day temperature
• 5
  5 hours of sunshine per day
• 13
  13 days with some rainfall
• 4
  4°C min night temperature
• 53
  53 mm of monthly rainfall

On average 53 mm (2.1 inches) of rain normally falls in Harmondsworth during April with rain falling on 13 days of the month.

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Harmondsworth weather in May

The average maximum daytime temperature in Harmondsworth in May is a comfortable 16°C (61°F), while the average minimum night-time temperature is a cold 6°C (43°F). You can expect on average 6 hours of sunshine a day in Harmondsworth during May.

• 16
  16°C max day temperature
• 6
  6 hours of sunshine per day
• 12
  12 days with some rainfall
• 6
  6°C min night temperature
• 57
  57 mm of monthly rainfall

On average 57 mm (2.2 inches) of rain normally falls in Harmondsworth during May with rain falling on 12 days of the month.

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Harmondsworth weather in June

The average maximum daytime temperature in Harmondsworth in June is a comfortable 19°C (66°F), while the average minimum night-time temperature is a cool 9°C (48°F). You can expect on average 7 hours of sunshine a day in Harmondsworth during June.

• 19
  19°C max day temperature
• 7
  7 hours of sunshine per day
• 11
  11 days with some rainfall
• 9
  9°C min night temperature
• 60
  60 mm of monthly rainfall

On average 60 mm (2.4 inches) of rain normally falls in Harmondsworth during June with rain falling on 11 days of the month.

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Harmondsworth weather in July

The average maximum daytime temperature in Harmondsworth in July is a warm 22°C (72°F), while the average minimum night-time temperature is a cool 12°C (54°F). You can expect on average 6 hours of sunshine a day in Harmondsworth during July.

• 22
  22°C max day temperature
• 6
  6 hours of sunshine per day
• 10
  10 days with some rainfall
• 12
  12°C min night temperature
• 41
  41 mm of monthly rainfall

On average 41 mm (1.6 inches) of rain normally falls in Harmondsworth during July with rain falling on 10 days of the month.

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Harmondsworth weather in August

The average maximum daytime temperature in Harmondsworth in August is a warm 22°C (72°F), while the average minimum night-time temperature is a cool 11°C (52°F). You can expect on average 6 hours of sunshine a day in Harmondsworth during August.

• 22
  22°C max day temperature
• 6
  6 hours of sunshine per day
• 11
  11 days with some rainfall
• 11
  11°C min night temperature
• 53
  53 mm of monthly rainfall

On average 53 mm (2.1 inches) of rain normally falls in Harmondsworth during August with rain falling on 11 days of the month.

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Harmondsworth weather in September

The average maximum daytime temperature in Harmondsworth in September is a comfortable 18°C (64°F), while the average minimum night-time temperature is a cool 9°C (48°F). You can expect on average 5 hours of sunshine a day in Harmondsworth during September.

• 18
  18°C max day temperature
• 5
  5 hours of sunshine per day
• 12
  12 days with some rainfall
• 9
  9°C min night temperature
• 72
  72 mm of monthly rainfall

On average 72 mm (2.8 inches) of rain normally falls in Harmondsworth during September with rain falling on 12 days of the month.

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Harmondsworth weather in October

The average maximum daytime temperature in Harmondsworth in October is a comfortable 14°C (57°F), while the average minimum night-time temperature is a cold 7°C (45°F). You can expect on average 3 hours of sunshine a day in Harmondsworth during October.

• 14
  14°C max day temperature
• 3
  3 hours of sunshine per day
• 14
  14 days with some rainfall
• 7
  7°C min night temperature
• 79
  79 mm of monthly rainfall

On average 79 mm (3.1 inches) of rain normally falls in Harmondsworth during October with rain falling on 14 days of the month.

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Harmondsworth weather in November

The average maximum daytime temperature in Harmondsworth in November is a cool 10°C (50°F), while the average minimum night-time temperature is a cold 3°C (37°F). You can expect on average 2 hours of sunshine a day in Harmondsworth during November.

• 10
  10°C max day temperature
• 2
  2 hours of sunshine per day
• 15
  15 days with some rainfall
• 3
  3°C min night temperature
• 74
  74 mm of monthly rainfall

On average 74 mm (2.9 inches) of rain normally falls in Harmondsworth during November with rain falling on 15 days of the month.

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Harmondsworth weather in December

The average maximum daytime temperature in Harmondsworth in December is a cool 8°C (46°F), while the average minimum night-time temperature is a cold 2°C (36°F). You can expect on average 2 hours of sunshine a day in Harmondsworth during December.

• 8
  8°C max day temperature
• 2
  2 hours of sunshine per day
• 15
  15 days with some rainfall
• 2
  2°C min night temperature
• 79
  79 mm of monthly rainfall

On average 79 mm (3.1 inches) of rain normally falls in Harmondsworth during December with rain falling on 15 days of the month.

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