Castlebar weather by month

Check out Castlebar weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature in Castlebar (°F)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
45°F maximum daytime temperature in January in Castlebar45
46°F maximum daytime temperature in February in Castlebar46
48°F maximum daytime temperature in March in Castlebar48
54°F maximum daytime temperature in April in Castlebar54
57°F maximum daytime temperature in May in Castlebar57
63°F maximum daytime temperature in June in Castlebar63
64°F maximum daytime temperature in July in Castlebar64
64°F maximum daytime temperature in August in Castlebar64
61°F maximum daytime temperature in September in Castlebar61
55°F maximum daytime temperature in October in Castlebar55
50°F maximum daytime temperature in November in Castlebar50
46°F maximum daytime temperature in December in Castlebar46
Min temperature (night-time)
36°F minimum night-time temperature in January in Castlebar36
36°F minimum night-time temperature in February in Castlebar36
37°F minimum night-time temperature in March in Castlebar37
39°F minimum night-time temperature in April in Castlebar39
43°F minimum night-time temperature in May in Castlebar43
48°F minimum night-time temperature in June in Castlebar48
50°F minimum night-time temperature in July in Castlebar50
50°F minimum night-time temperature in August in Castlebar50
48°F minimum night-time temperature in September in Castlebar48
45°F minimum night-time temperature in October in Castlebar45
39°F minimum night-time temperature in November in Castlebar39
37°F minimum night-time temperature in December in Castlebar37
Heat & Humidity
No heat & humidity in January in Castlebar0
No heat & humidity in February in Castlebar0
No heat & humidity in March in Castlebar0
No heat & humidity in April in Castlebar0
No heat & humidity in May in Castlebar0
No heat & humidity in June in Castlebar0
No heat & humidity in July in Castlebar0
No heat & humidity in August in Castlebar0
No heat & humidity in September in Castlebar0
No heat & humidity in October in Castlebar0
No heat & humidity in November in Castlebar0
No heat & humidity in December in Castlebar0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & UV index in Castlebar

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily hours of sunshine
Daily hours of daylight
8 hours of daylight per day in January in Castlebar8
10 hours of daylight per day in February in Castlebar10
12 hours of daylight per day in March in Castlebar12
14 hours of daylight per day in April in Castlebar14
16 hours of daylight per day in May in Castlebar16
17 hours of daylight per day in June in Castlebar17
16 hours of daylight per day in July in Castlebar16
15 hours of daylight per day in August in Castlebar15
13 hours of daylight per day in September in Castlebar13
11 hours of daylight per day in October in Castlebar11
9 hours of daylight per day in November in Castlebar9
8 hours of daylight per day in December in Castlebar8
UV Index (Maximum)
No UV (maximum) index in January in Castlebar0
UV (maximum) index 1 (Low) in February in Castlebar1
UV (maximum) index 2 (Low) in March in Castlebar2
UV (maximum) index 4 (Moderate) in April in Castlebar4
UV (maximum) index 5 (Moderate) in May in Castlebar5
UV (maximum) index 6 (High) in June in Castlebar6
UV (maximum) index 6 (High) in July in Castlebar6
UV (maximum) index 5 (Moderate) in August in Castlebar5
UV (maximum) index 4 (Moderate) in September in Castlebar4
UV (maximum) index 2 (Low) in October in Castlebar2
UV (maximum) index 1 (Low) in November in Castlebar1
No UV (maximum) index in December in Castlebar0

Rainfall in Castlebar

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
24 days with some rainfall in January in Castlebar24
19 days with some rainfall in February in Castlebar19
22 days with some rainfall in March in Castlebar22
17 days with some rainfall in April in Castlebar17
19 days with some rainfall in May in Castlebar19
17 days with some rainfall in June in Castlebar17
17 days with some rainfall in July in Castlebar17
20 days with some rainfall in August in Castlebar20
21 days with some rainfall in September in Castlebar21
23 days with some rainfall in October in Castlebar23
23 days with some rainfall in November in Castlebar23
23 days with some rainfall in December in Castlebar23
Average monthly rainfall (inches)
5.1 inches monthly rainfall in January in Castlebar5.1
3.3 inches monthly rainfall in February in Castlebar3.3
3.9 inches monthly rainfall in March in Castlebar3.9
2.6 inches monthly rainfall in April in Castlebar2.6
3.1 inches monthly rainfall in May in Castlebar3.1
2.8 inches monthly rainfall in June in Castlebar2.8
2.7 inches monthly rainfall in July in Castlebar2.7
3.7 inches monthly rainfall in August in Castlebar3.7
4.4 inches monthly rainfall in September in Castlebar4.4
5.2 inches monthly rainfall in October in Castlebar5.2
5.3 inches monthly rainfall in November in Castlebar5.3
5.1 inches monthly rainfall in December in Castlebar5.1

More about Castlebar

Castlebar by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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The climate guide for Ireland (Castlebar) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Castlebar?

Castlebar has a temperate climate with warm summers and some rainfall in all months.

Castlebar weather in January

Expect daytime maximum temperatures of 45°F in Castlebar, Ireland in January based on long-term weather averages. There are 2 hours of sunshine per day on average with 24 days with some rainfall and typically 5.1 inches of rainfall in the month.

  • 45°F maximum daytime temperature in January in Castlebar45
    45°F max day temperature
  • 2 hours of sunshine per day
  • 24 days with some rainfall in January in Castlebar24
    24 days with some rainfall
  • 36°F minimum night-time temperature in January in Castlebar36
    36°F min night temperature
  • 8 hours of daylight per day in January in Castlebar8
    8 hours of daylight per day
  • No heat & humidity in January in Castlebar0
    No heat & humidity
  • 5.1 inches monthly rainfall in January in Castlebar5.1
    5.1 inches of monthly rainfall
  • No UV (maximum) index in January in Castlebar0
    No UV (Maximum) Index UV index

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Castlebar weather in February

Expect daytime maximum temperatures of 46°F in Castlebar, Ireland in February based on long-term weather averages. There are 2 hours of sunshine per day on average with 19 days with some rainfall and typically 3.3 inches of rainfall in the month.

  • 46°F maximum daytime temperature in February in Castlebar46
    46°F max day temperature
  • 2 hours of sunshine per day
  • 19 days with some rainfall in February in Castlebar19
    19 days with some rainfall
  • 36°F minimum night-time temperature in February in Castlebar36
    36°F min night temperature
  • 10 hours of daylight per day in February in Castlebar10
    10 hours of daylight per day
  • No heat & humidity in February in Castlebar0
    No heat & humidity
  • 3.3 inches monthly rainfall in February in Castlebar3.3
    3.3 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in February in Castlebar1
    1 (Low) UV index

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Castlebar weather in March

Expect daytime maximum temperatures of 48°F in Castlebar, Ireland in March based on long-term weather averages. There are 3 hours of sunshine per day on average with 22 days with some rainfall and typically 3.9 inches of rainfall in the month.

  • 48°F maximum daytime temperature in March in Castlebar48
    48°F max day temperature
  • 3 hours of sunshine per day
  • 22 days with some rainfall in March in Castlebar22
    22 days with some rainfall
  • 37°F minimum night-time temperature in March in Castlebar37
    37°F min night temperature
  • 12 hours of daylight per day in March in Castlebar12
    12 hours of daylight per day
  • No heat & humidity in March in Castlebar0
    No heat & humidity
  • 3.9 inches monthly rainfall in March in Castlebar3.9
    3.9 inches of monthly rainfall
  • UV (maximum) index 2 (Low) in March in Castlebar2
    2 (Low) UV index

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Castlebar weather in April

Expect daytime maximum temperatures of 54°F in Castlebar, Ireland in April based on long-term weather averages. There are 5 hours of sunshine per day on average with 17 days with some rainfall and typically 2.6 inches of rainfall in the month.

  • 54°F maximum daytime temperature in April in Castlebar54
    54°F max day temperature
  • 5 hours of sunshine per day
  • 17 days with some rainfall in April in Castlebar17
    17 days with some rainfall
  • 39°F minimum night-time temperature in April in Castlebar39
    39°F min night temperature
  • 14 hours of daylight per day in April in Castlebar14
    14 hours of daylight per day
  • No heat & humidity in April in Castlebar0
    No heat & humidity
  • 2.6 inches monthly rainfall in April in Castlebar2.6
    2.6 inches of monthly rainfall
  • UV (maximum) index 4 (Moderate) in April in Castlebar4
    4 (Moderate) UV index

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Castlebar weather in May

Expect daytime maximum temperatures of 57°F in Castlebar, Ireland in May based on long-term weather averages. There are 5 hours of sunshine per day on average with 19 days with some rainfall and typically 3.1 inches of rainfall in the month.

  • 57°F maximum daytime temperature in May in Castlebar57
    57°F max day temperature
  • 5 hours of sunshine per day
  • 19 days with some rainfall in May in Castlebar19
    19 days with some rainfall
  • 43°F minimum night-time temperature in May in Castlebar43
    43°F min night temperature
  • 16 hours of daylight per day in May in Castlebar16
    16 hours of daylight per day
  • No heat & humidity in May in Castlebar0
    No heat & humidity
  • 3.1 inches monthly rainfall in May in Castlebar3.1
    3.1 inches of monthly rainfall
  • UV (maximum) index 5 (Moderate) in May in Castlebar5
    5 (Moderate) UV index

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Castlebar weather in June

Expect daytime maximum temperatures of 63°F in Castlebar, Ireland in June based on long-term weather averages. There are 5 hours of sunshine per day on average with 17 days with some rainfall and typically 2.8 inches of rainfall in the month.

  • 63°F maximum daytime temperature in June in Castlebar63
    63°F max day temperature
  • 5 hours of sunshine per day
  • 17 days with some rainfall in June in Castlebar17
    17 days with some rainfall
  • 48°F minimum night-time temperature in June in Castlebar48
    48°F min night temperature
  • 17 hours of daylight per day in June in Castlebar17
    17 hours of daylight per day
  • No heat & humidity in June in Castlebar0
    No heat & humidity
  • 2.8 inches monthly rainfall in June in Castlebar2.8
    2.8 inches of monthly rainfall
  • UV (maximum) index 6 (High) in June in Castlebar6
    6 (High) UV index

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Castlebar weather in July

Expect daytime maximum temperatures of 64°F in Castlebar, Ireland in July based on long-term weather averages. There are 4 hours of sunshine per day on average with 17 days with some rainfall and typically 2.7 inches of rainfall in the month.

  • 64°F maximum daytime temperature in July in Castlebar64
    64°F max day temperature
  • 4 hours of sunshine per day
  • 17 days with some rainfall in July in Castlebar17
    17 days with some rainfall
  • 50°F minimum night-time temperature in July in Castlebar50
    50°F min night temperature
  • 16 hours of daylight per day in July in Castlebar16
    16 hours of daylight per day
  • No heat & humidity in July in Castlebar0
    No heat & humidity
  • 2.7 inches monthly rainfall in July in Castlebar2.7
    2.7 inches of monthly rainfall
  • UV (maximum) index 6 (High) in July in Castlebar6
    6 (High) UV index

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Castlebar weather in August

Expect daytime maximum temperatures of 64°F in Castlebar, Ireland in August based on long-term weather averages. There are 4 hours of sunshine per day on average with 20 days with some rainfall and typically 3.7 inches of rainfall in the month.

  • 64°F maximum daytime temperature in August in Castlebar64
    64°F max day temperature
  • 4 hours of sunshine per day
  • 20 days with some rainfall in August in Castlebar20
    20 days with some rainfall
  • 50°F minimum night-time temperature in August in Castlebar50
    50°F min night temperature
  • 15 hours of daylight per day in August in Castlebar15
    15 hours of daylight per day
  • No heat & humidity in August in Castlebar0
    No heat & humidity
  • 3.7 inches monthly rainfall in August in Castlebar3.7
    3.7 inches of monthly rainfall
  • UV (maximum) index 5 (Moderate) in August in Castlebar5
    5 (Moderate) UV index

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Castlebar weather in September

Expect daytime maximum temperatures of 61°F in Castlebar, Ireland in September based on long-term weather averages. There are 3 hours of sunshine per day on average with 21 days with some rainfall and typically 4.4 inches of rainfall in the month.

  • 61°F maximum daytime temperature in September in Castlebar61
    61°F max day temperature
  • 3 hours of sunshine per day
  • 21 days with some rainfall in September in Castlebar21
    21 days with some rainfall
  • 48°F minimum night-time temperature in September in Castlebar48
    48°F min night temperature
  • 13 hours of daylight per day in September in Castlebar13
    13 hours of daylight per day
  • No heat & humidity in September in Castlebar0
    No heat & humidity
  • 4.4 inches monthly rainfall in September in Castlebar4.4
    4.4 inches of monthly rainfall
  • UV (maximum) index 4 (Moderate) in September in Castlebar4
    4 (Moderate) UV index

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Castlebar weather in October

Expect daytime maximum temperatures of 55°F in Castlebar, Ireland in October based on long-term weather averages. There are 2 hours of sunshine per day on average with 23 days with some rainfall and typically 5.2 inches of rainfall in the month.

  • 55°F maximum daytime temperature in October in Castlebar55
    55°F max day temperature
  • 2 hours of sunshine per day
  • 23 days with some rainfall in October in Castlebar23
    23 days with some rainfall
  • 45°F minimum night-time temperature in October in Castlebar45
    45°F min night temperature
  • 11 hours of daylight per day in October in Castlebar11
    11 hours of daylight per day
  • No heat & humidity in October in Castlebar0
    No heat & humidity
  • 5.2 inches monthly rainfall in October in Castlebar5.2
    5.2 inches of monthly rainfall
  • UV (maximum) index 2 (Low) in October in Castlebar2
    2 (Low) UV index

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Castlebar weather in November

Expect daytime maximum temperatures of 50°F in Castlebar, Ireland in November based on long-term weather averages. There are 2 hours of sunshine per day on average with 23 days with some rainfall and typically 5.3 inches of rainfall in the month.

  • 50°F maximum daytime temperature in November in Castlebar50
    50°F max day temperature
  • 2 hours of sunshine per day
  • 23 days with some rainfall in November in Castlebar23
    23 days with some rainfall
  • 39°F minimum night-time temperature in November in Castlebar39
    39°F min night temperature
  • 9 hours of daylight per day in November in Castlebar9
    9 hours of daylight per day
  • No heat & humidity in November in Castlebar0
    No heat & humidity
  • 5.3 inches monthly rainfall in November in Castlebar5.3
    5.3 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in November in Castlebar1
    1 (Low) UV index

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Castlebar weather in December

Expect daytime maximum temperatures of 46°F in Castlebar, Ireland in December based on long-term weather averages. There is 1 hour of sunshine per day on average with 23 days with some rainfall and typically 5.1 inches of rainfall in the month.

  • 46°F maximum daytime temperature in December in Castlebar46
    46°F max day temperature
  • 1 hour of sunshine per day
  • 23 days with some rainfall in December in Castlebar23
    23 days with some rainfall
  • 37°F minimum night-time temperature in December in Castlebar37
    37°F min night temperature
  • 8 hours of daylight per day in December in Castlebar8
    8 hours of daylight per day
  • No heat & humidity in December in Castlebar0
    No heat & humidity
  • 5.1 inches monthly rainfall in December in Castlebar5.1
    5.1 inches of monthly rainfall
  • No UV (maximum) index in December in Castlebar0
    No UV (Maximum) Index UV index

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More about Castlebar

Castlebar by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for Ireland

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The climate guide for Ireland (Castlebar) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Compare Castlebar weather with the UK

The weather chart below compares the average monthly maximum daytime temperature for Castlebar, County Mayo, Ireland and the UK (London).

Maximum daytime temperature (°F)

Castlebar, County Mayo, Ireland
UK (London)
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Metric (°C)  |  Imperial (°F)

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