Letterkenny weather by month

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

Temperature in Letterkenny (°F)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
45°F maximum daytime temperature in January in Letterkenny45
45°F maximum daytime temperature in February in Letterkenny45
46°F maximum daytime temperature in March in Letterkenny46
52°F maximum daytime temperature in April in Letterkenny52
55°F maximum daytime temperature in May in Letterkenny55
61°F maximum daytime temperature in June in Letterkenny61
63°F maximum daytime temperature in July in Letterkenny63
63°F maximum daytime temperature in August in Letterkenny63
59°F maximum daytime temperature in September in Letterkenny59
54°F maximum daytime temperature in October in Letterkenny54
48°F maximum daytime temperature in November in Letterkenny48
45°F maximum daytime temperature in December in Letterkenny45
Min temperature (night-time)
34°F minimum night-time temperature in January in Letterkenny34
34°F minimum night-time temperature in February in Letterkenny34
36°F minimum night-time temperature in March in Letterkenny36
37°F minimum night-time temperature in April in Letterkenny37
41°F minimum night-time temperature in May in Letterkenny41
46°F minimum night-time temperature in June in Letterkenny46
50°F minimum night-time temperature in July in Letterkenny50
50°F minimum night-time temperature in August in Letterkenny50
46°F minimum night-time temperature in September in Letterkenny46
45°F minimum night-time temperature in October in Letterkenny45
37°F minimum night-time temperature in November in Letterkenny37
36°F minimum night-time temperature in December in Letterkenny36
Heat & Humidity
No heat & humidity in January in Letterkenny0
No heat & humidity in February in Letterkenny0
No heat & humidity in March in Letterkenny0
No heat & humidity in April in Letterkenny0
No heat & humidity in May in Letterkenny0
No heat & humidity in June in Letterkenny0
No heat & humidity in July in Letterkenny0
No heat & humidity in August in Letterkenny0
No heat & humidity in September in Letterkenny0
No heat & humidity in October in Letterkenny0
No heat & humidity in November in Letterkenny0
No heat & humidity in December in Letterkenny0

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

Sunshine & UV index in Letterkenny

  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 Letterkenny8
10 hours of daylight per day in February in Letterkenny10
12 hours of daylight per day in March in Letterkenny12
14 hours of daylight per day in April in Letterkenny14
16 hours of daylight per day in May in Letterkenny16
17 hours of daylight per day in June in Letterkenny17
17 hours of daylight per day in July in Letterkenny17
15 hours of daylight per day in August in Letterkenny15
13 hours of daylight per day in September in Letterkenny13
10 hours of daylight per day in October in Letterkenny10
8 hours of daylight per day in November in Letterkenny8
7 hours of daylight per day in December in Letterkenny7
UV Index (Maximum)
No UV (maximum) index in January in Letterkenny0
UV (maximum) index 1 (Low) in February in Letterkenny1
UV (maximum) index 2 (Low) in March in Letterkenny2
UV (maximum) index 3 (Moderate) in April in Letterkenny3
UV (maximum) index 5 (Moderate) in May in Letterkenny5
UV (maximum) index 6 (High) in June in Letterkenny6
UV (maximum) index 6 (High) in July in Letterkenny6
UV (maximum) index 5 (Moderate) in August in Letterkenny5
UV (maximum) index 3 (Moderate) in September in Letterkenny3
UV (maximum) index 2 (Low) in October in Letterkenny2
UV (maximum) index 1 (Low) in November in Letterkenny1
No UV (maximum) index in December in Letterkenny0

Rainfall in Letterkenny

  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 Letterkenny24
19 days with some rainfall in February in Letterkenny19
22 days with some rainfall in March in Letterkenny22
18 days with some rainfall in April in Letterkenny18
19 days with some rainfall in May in Letterkenny19
19 days with some rainfall in June in Letterkenny19
20 days with some rainfall in July in Letterkenny20
21 days with some rainfall in August in Letterkenny21
22 days with some rainfall in September in Letterkenny22
23 days with some rainfall in October in Letterkenny23
23 days with some rainfall in November in Letterkenny23
23 days with some rainfall in December in Letterkenny23
Average monthly rainfall (inches)
5.4 inches monthly rainfall in January in Letterkenny5.4
3.8 inches monthly rainfall in February in Letterkenny3.8
3.9 inches monthly rainfall in March in Letterkenny3.9
2.9 inches monthly rainfall in April in Letterkenny2.9
3.2 inches monthly rainfall in May in Letterkenny3.2
3.1 inches monthly rainfall in June in Letterkenny3.1
3.4 inches monthly rainfall in July in Letterkenny3.4
3.9 inches monthly rainfall in August in Letterkenny3.9
4.7 inches monthly rainfall in September in Letterkenny4.7
5.2 inches monthly rainfall in October in Letterkenny5.2
5.4 inches monthly rainfall in November in Letterkenny5.4
5.6 inches monthly rainfall in December in Letterkenny5.6

More about Letterkenny

Letterkenny by month

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

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The climate guide for Ireland (Letterkenny) 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 Letterkenny?

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

Letterkenny weather in January

Expect daytime maximum temperatures of 45°F in Letterkenny, Ireland in January based on long-term weather averages. There is 1 hour of sunshine per day on average with 24 days with some rainfall and typically 5.4 inches of rainfall in the month.

  • 45°F maximum daytime temperature in January in Letterkenny45
    45°F max day temperature
  • 1 hour of sunshine per day
  • 24 days with some rainfall in January in Letterkenny24
    24 days with some rainfall
  • 34°F minimum night-time temperature in January in Letterkenny34
    34°F min night temperature
  • 8 hours of daylight per day in January in Letterkenny8
    8 hours of daylight per day
  • No heat & humidity in January in Letterkenny0
    No heat & humidity
  • 5.4 inches monthly rainfall in January in Letterkenny5.4
    5.4 inches of monthly rainfall
  • No UV (maximum) index in January in Letterkenny0
    No UV (Maximum) Index UV index

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Letterkenny weather in February

Expect daytime maximum temperatures of 45°F in Letterkenny, 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 3.8 inches of rainfall in the month.

  • 45°F maximum daytime temperature in February in Letterkenny45
    45°F max day temperature
  • 2 hours of sunshine per day
  • 19 days with some rainfall in February in Letterkenny19
    19 days with some rainfall
  • 34°F minimum night-time temperature in February in Letterkenny34
    34°F min night temperature
  • 10 hours of daylight per day in February in Letterkenny10
    10 hours of daylight per day
  • No heat & humidity in February in Letterkenny0
    No heat & humidity
  • 3.8 inches monthly rainfall in February in Letterkenny3.8
    3.8 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in February in Letterkenny1
    1 (Low) UV index

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Letterkenny weather in March

Expect daytime maximum temperatures of 46°F in Letterkenny, 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.

  • 46°F maximum daytime temperature in March in Letterkenny46
    46°F max day temperature
  • 3 hours of sunshine per day
  • 22 days with some rainfall in March in Letterkenny22
    22 days with some rainfall
  • 36°F minimum night-time temperature in March in Letterkenny36
    36°F min night temperature
  • 12 hours of daylight per day in March in Letterkenny12
    12 hours of daylight per day
  • No heat & humidity in March in Letterkenny0
    No heat & humidity
  • 3.9 inches monthly rainfall in March in Letterkenny3.9
    3.9 inches of monthly rainfall
  • UV (maximum) index 2 (Low) in March in Letterkenny2
    2 (Low) UV index

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Letterkenny weather in April

Expect daytime maximum temperatures of 52°F in Letterkenny, Ireland in April based on long-term weather averages. There are 5 hours of sunshine per day on average with 18 days with some rainfall and typically 2.9 inches of rainfall in the month.

  • 52°F maximum daytime temperature in April in Letterkenny52
    52°F max day temperature
  • 5 hours of sunshine per day
  • 18 days with some rainfall in April in Letterkenny18
    18 days with some rainfall
  • 37°F minimum night-time temperature in April in Letterkenny37
    37°F min night temperature
  • 14 hours of daylight per day in April in Letterkenny14
    14 hours of daylight per day
  • No heat & humidity in April in Letterkenny0
    No heat & humidity
  • 2.9 inches monthly rainfall in April in Letterkenny2.9
    2.9 inches of monthly rainfall
  • UV (maximum) index 3 (Moderate) in April in Letterkenny3
    3 (Moderate) UV index

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Letterkenny weather in May

Expect daytime maximum temperatures of 55°F in Letterkenny, Ireland in May based on long-term weather averages. There are 6 hours of sunshine per day on average with 19 days with some rainfall and typically 3.2 inches of rainfall in the month.

  • 55°F maximum daytime temperature in May in Letterkenny55
    55°F max day temperature
  • 6 hours of sunshine per day
  • 19 days with some rainfall in May in Letterkenny19
    19 days with some rainfall
  • 41°F minimum night-time temperature in May in Letterkenny41
    41°F min night temperature
  • 16 hours of daylight per day in May in Letterkenny16
    16 hours of daylight per day
  • No heat & humidity in May in Letterkenny0
    No heat & humidity
  • 3.2 inches monthly rainfall in May in Letterkenny3.2
    3.2 inches of monthly rainfall
  • UV (maximum) index 5 (Moderate) in May in Letterkenny5
    5 (Moderate) UV index

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Letterkenny weather in June

Expect daytime maximum temperatures of 61°F in Letterkenny, Ireland in June 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.

  • 61°F maximum daytime temperature in June in Letterkenny61
    61°F max day temperature
  • 5 hours of sunshine per day
  • 19 days with some rainfall in June in Letterkenny19
    19 days with some rainfall
  • 46°F minimum night-time temperature in June in Letterkenny46
    46°F min night temperature
  • 17 hours of daylight per day in June in Letterkenny17
    17 hours of daylight per day
  • No heat & humidity in June in Letterkenny0
    No heat & humidity
  • 3.1 inches monthly rainfall in June in Letterkenny3.1
    3.1 inches of monthly rainfall
  • UV (maximum) index 6 (High) in June in Letterkenny6
    6 (High) UV index

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Letterkenny weather in July

Expect daytime maximum temperatures of 63°F in Letterkenny, Ireland in July based on long-term weather averages. There are 4 hours of sunshine per day on average with 20 days with some rainfall and typically 3.4 inches of rainfall in the month.

  • 63°F maximum daytime temperature in July in Letterkenny63
    63°F max day temperature
  • 4 hours of sunshine per day
  • 20 days with some rainfall in July in Letterkenny20
    20 days with some rainfall
  • 50°F minimum night-time temperature in July in Letterkenny50
    50°F min night temperature
  • 17 hours of daylight per day in July in Letterkenny17
    17 hours of daylight per day
  • No heat & humidity in July in Letterkenny0
    No heat & humidity
  • 3.4 inches monthly rainfall in July in Letterkenny3.4
    3.4 inches of monthly rainfall
  • UV (maximum) index 6 (High) in July in Letterkenny6
    6 (High) UV index

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Letterkenny weather in August

Expect daytime maximum temperatures of 63°F in Letterkenny, Ireland in August based on long-term weather averages. There are 4 hours of sunshine per day on average with 21 days with some rainfall and typically 3.9 inches of rainfall in the month.

  • 63°F maximum daytime temperature in August in Letterkenny63
    63°F max day temperature
  • 4 hours of sunshine per day
  • 21 days with some rainfall in August in Letterkenny21
    21 days with some rainfall
  • 50°F minimum night-time temperature in August in Letterkenny50
    50°F min night temperature
  • 15 hours of daylight per day in August in Letterkenny15
    15 hours of daylight per day
  • No heat & humidity in August in Letterkenny0
    No heat & humidity
  • 3.9 inches monthly rainfall in August in Letterkenny3.9
    3.9 inches of monthly rainfall
  • UV (maximum) index 5 (Moderate) in August in Letterkenny5
    5 (Moderate) UV index

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Letterkenny weather in September

Expect daytime maximum temperatures of 59°F in Letterkenny, Ireland in September based on long-term weather averages. There are 3 hours of sunshine per day on average with 22 days with some rainfall and typically 4.7 inches of rainfall in the month.

  • 59°F maximum daytime temperature in September in Letterkenny59
    59°F max day temperature
  • 3 hours of sunshine per day
  • 22 days with some rainfall in September in Letterkenny22
    22 days with some rainfall
  • 46°F minimum night-time temperature in September in Letterkenny46
    46°F min night temperature
  • 13 hours of daylight per day in September in Letterkenny13
    13 hours of daylight per day
  • No heat & humidity in September in Letterkenny0
    No heat & humidity
  • 4.7 inches monthly rainfall in September in Letterkenny4.7
    4.7 inches of monthly rainfall
  • UV (maximum) index 3 (Moderate) in September in Letterkenny3
    3 (Moderate) UV index

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Letterkenny weather in October

Expect daytime maximum temperatures of 54°F in Letterkenny, 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.

  • 54°F maximum daytime temperature in October in Letterkenny54
    54°F max day temperature
  • 2 hours of sunshine per day
  • 23 days with some rainfall in October in Letterkenny23
    23 days with some rainfall
  • 45°F minimum night-time temperature in October in Letterkenny45
    45°F min night temperature
  • 10 hours of daylight per day in October in Letterkenny10
    10 hours of daylight per day
  • No heat & humidity in October in Letterkenny0
    No heat & humidity
  • 5.2 inches monthly rainfall in October in Letterkenny5.2
    5.2 inches of monthly rainfall
  • UV (maximum) index 2 (Low) in October in Letterkenny2
    2 (Low) UV index

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Letterkenny weather in November

Expect daytime maximum temperatures of 48°F in Letterkenny, 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 5.4 inches of rainfall in the month.

  • 48°F maximum daytime temperature in November in Letterkenny48
    48°F max day temperature
  • 2 hours of sunshine per day
  • 23 days with some rainfall in November in Letterkenny23
    23 days with some rainfall
  • 37°F minimum night-time temperature in November in Letterkenny37
    37°F min night temperature
  • 8 hours of daylight per day in November in Letterkenny8
    8 hours of daylight per day
  • No heat & humidity in November in Letterkenny0
    No heat & humidity
  • 5.4 inches monthly rainfall in November in Letterkenny5.4
    5.4 inches of monthly rainfall
  • UV (maximum) index 1 (Low) in November in Letterkenny1
    1 (Low) UV index

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Letterkenny weather in December

Expect daytime maximum temperatures of 45°F in Letterkenny, 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 5.6 inches of rainfall in the month.

  • 45°F maximum daytime temperature in December in Letterkenny45
    45°F max day temperature
  • 1 hour of sunshine per day
  • 23 days with some rainfall in December in Letterkenny23
    23 days with some rainfall
  • 36°F minimum night-time temperature in December in Letterkenny36
    36°F min night temperature
  • 7 hours of daylight per day in December in Letterkenny7
    7 hours of daylight per day
  • No heat & humidity in December in Letterkenny0
    No heat & humidity
  • 5.6 inches monthly rainfall in December in Letterkenny5.6
    5.6 inches of monthly rainfall
  • No UV (maximum) index in December in Letterkenny0
    No UV (Maximum) Index UV index

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More about Letterkenny

Letterkenny by month

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

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The climate guide for Ireland (Letterkenny) 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 Letterkenny weather with the UK

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

Maximum daytime temperature (°F)

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

Metric (°C)  |  Imperial (°F)

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