Climate and monthly weather forecastShannon, Ireland
Climate and monthly weather forecast
The climate of Shannon
Shannon, Ireland experiences a Marine West Coast climate, notably characterized by the warm summer, according to the Köppen-Geiger climate classification. Geographically positioned on the western coast of Ireland, this location typically encounters mild, humid and overcast weather.Throughout the year, the temperatures rarely dip below the freezing point. Average high temperatures range from 7.8°C (46°F) in the beginning of the year and gradually increase to around 18°C (64.4°F) at the peak of summer before falling back to around 8°C (46.4°F) by year's end. Conversely, the average low temperatures shift from 3.1°C (37.6°F) at the start of the year, climbing to 11.1°C (52°F) during summer and decline to 3.5°C (38.3°F) by December.
Relative humidity remains relatively high all year, beginning at 89% in January and dipping slightly to 84% in April, before ascending back to 90% by November and December. Correspondingly, the monthly average rainfall varies from 33mm (1.3") in September to 56mm (2.2") in December with an associated increase in rainfall days from 14.8 in February to 20.4 in August. Snowfall is scarce, with only measurable amount of 21mm (0.83") occurring in December and January.
One unusual weather pattern includes no recorded snowfall from April to November. One may evidently observe the shifting amount of daylight, where it reaches a yearly high of 16.8 hours in June and falls to a low of 7.7 hours in December.
The best time to visit Shannon
The best time to visit Shannon would arguably be during the late spring and early summer months from May to July. This period offers a balmy temperature range between 12.3°C (54.1°F) to 18°C (64.4°F), paired with increased daylight hours, stretching from 14 hours to 16.8 hours. Furthermore, the sea temperature is relatively warm during these months, varying from 11.4°C (52.5°F) to 15.1°C (59.2°F), allowing for enjoyable seaside activities.The worst time to visit Shannon
The least favorable period for visiting Shannon can be regarded as the winter months from December to February. The combination of low temperatures, varying from 7.8°C (46°F) to 8.3°C (46.9°F), short daylight hours dwindling from 7.7 hours to 8.3 hours, and potentially disruptive snowfall makes leisure activities considerably less enjoyable.Spring weather in Shannon
Spring in Shannon, extending from March to May, observes a gradual rise in temperatures. March records a high of 9.6°C (49.3°F) and a low of 2.9°C (37.2°F), whereas these change to 14.3°C (57.7°F) and 6.6°C (43.9°F) by May. This season's rainfall falls between 35mm (1.38") to 39mm (1.54"), whereas relative humidity drops slightly from 85% in March to 84% in April and then increases slightly to 85% in May. Shannon experiences longer daylight hours, expanding from 11.9 hours in March to 15.8 hours in May, coupled with ample sunshine hours, ranging from 5 hours to 6.1 hours.Summer weather in Shannon
Shannon's summer months, from June to August, illustrate weather conditions that are quite favorable. Average high temperatures fluctuate from 17°C (62.6°F) to 18°C (64.4°F), while lows temperately vary between 9°C (48.2°F) and 11.1°C (52°F). Rainfall ranges from 41mm (1.61") to 50mm (1.97"), and Shannon sees sunlight for approximately 15.8 hours to 16.3 hours daily. The sea temperatures mature at this time of the year, elevating to between 15.1°C (59.2°F) and 15.8°C (60.4°F).Autumn weather in Shannon
Autumn, extending from September to November, in Shannon brings a gradual cooling of temperatures, ranging from a high of 15.8°C (60.4°F) in September to 9.6°C (49.3°F) in November. Correspondingly, low temperatures fluctuate from 9.3°C (48.7°F) in September to 4.9°C (40.8°F) in November. Rainfall slightly increases from 33mm (1.3") to 53mm (2.09") during these months. While daylight hours decrease from 12.7 hours in September to 8.7 hours in November, sunshine hours slowly drop from 5.6 hours to 4.1 hours.Winter weather in Shannon
Shannon's winter season from December to February represents the coldest and shortest days of the year. High temperatures decline from 8°C (46.4°F) in December to 7.8°C (46°F) in January and then rise to 8.3°C (46.9°F) in February. Low temperatures sway from 3.5°C (38.3°F) to 3.1°C (37.6°F) within this period. Snowfall of 21mm (0.83") and 18mm (0.71") can be expected in December and January, respectively. The daylight hours during these months decrease to between 7.7 hours and 8.3 hours.Weather in January
The onset of the year sees Shannon, Ireland, enticing with its relative cold. January's temperatures present a marked difference from the mild December, with daily averages swinging between 3.1°C (37.6°F) at night and 7.8°C (46°F) during the day. Weather in January »Weather in February
Advancing into February, Shannon’s weather depicts a subtle shift in temperature compared to January. The city remains cold, but a marginal increase in the daytime temperature to 8.3°C (46.9°F) offers a bit of solace to the inhabitants. Weather in February »Weather in March
March beckons spring with open arms in Shannon, offering a warmer welcome than February. This month observes the temperature reaching a comfortable 9.6°C (49.3°F) during the day, hinting at the departure of winter. The snowfall level becomes unnoticeable, and rainfall slightly subsides. Weather in March »Weather in April
April is the month where Shannon starts to bustle with activity, drawing in more visitors due to improved weather conditions. The rise in temperature from March to 12.3°C (54.1°F) during the day is noticeable, marking an indisputable advent of spring. Weather in April »Weather in May
The arrival of May induces significant changes in the weather of Shannon. Transitioning from April, the city witnesses the real essence of spring as daytime temperatures elevate to a comfortable 14.3°C (57.7°F). Rainfall remains consistent throughout the month while snowfall is relatively absent. Weather in May »Weather in June
Shannon further warms up in June, marking the onset of the summer season. The most evident change from May is the noticeable spike in daytime temperature, which ascends to 17°C (62.6°F). In spite of summer, rainfall occurs throughout the month. Weather in June »Weather in July
July is the heart of summer in Shannon, manifesting the warmest weather so far. The arrival of this month brings an increase in temperature to a peak high of 18°C (64.4°F) during daytime. Despite the elevated temperatures, the rain showers continue. Weather in July »Weather in August
August represents the final full month of summer in Shannon, wherein the daytime temperature perceivably starts to dip, going down from July’s peak to 17.5°C (63.5°F). Upsurge in rainfall is noted when compared to July, though it does little to dampen the city's summer spirit. Weather in August »Weather in September
Transitioning into September, Shannon’s weather manifests autumn's arrival with a decrease in temperature, dropping to 15.8°C (60.4°F) during the day. The rainfall decreases slightly compared to the previous month, thus ushering in more dry days. Weather in September »Weather in October
October's weather in Shannon is characterized by a palpable feel of autumn as the day temperatures fall further to 13.5°C (56.3°F). As the climate transitions from September, rainfall becomes slightly more frequent. The days become progressively shorter as the city mates with the autumn season completely. Weather in October »Weather in November
As winter subtly creeps in, November witnesses a significant dip in temperature in Shannon falling to 9.6°C (49.3°F) during the day. It becomes the rainiest month of the year, with a high downpour amount of 53mm (2.09"). Despite the colder weather and increased rainfall, it enhances the city's splendid appeal. Weather in November »Weather in December
December greets Shannon with the advent of winter, introducing colder conditions as compared to November. With the daytime temperature dropping to 8°C (46.4°F), winters make a grand entry. Rainfall is consistent, keeping up to November's precedence. Weather in December »Updated: Jan 27, 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
Shannon's January weather reaches an average high of 7.8°C (46°F) and an average low of 3.1°C (37.6°F), making it the coldest month.
Throughout the year, in Shannon, Ireland, there are 204.6 rainfall days, and 512mm (20.16") of precipitation is accumulated.
January through March and December are months with snowfall.
In Shannon, Ireland, during the entire year, snow falls for 3.2 days and aggregates up to 57mm (2.24") of snow.
January and December, with an average of 4h of sunshine, are months with the least sunshine in Shannon, Ireland.
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2.
With an average sea temperature of 9.4°C (48.9°F), March is the month with the coldest seawater in Shannon, Ireland.
With an average relative humidity of 84%, April is the least humid month in Shannon.
April through November are months without snowfall in Shannon.
The months with the highest UV index are May and June, with an average maximum UV index of 4.
The month with the longest days in Shannon is June, with an average of 16h and 48min of daylight.
The month with the most sunshine is June, with an average of 7.3h of sunshine.
The average temperatures in Shannon, Ireland, reach their apex in July, averaging 18°C (64.4°F) at the high end and 11.1°C (52°F) at the low end.
With an average sea temperature of 15.8°C (60.4°F), August is the month with the warmest seawater in Shannon.
September is the month with the least rainfall. Rain falls for 14.9 days and accumulates 33mm (1.3") of precipitation.
On Sunday, 27. October 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from IST to GMT. Daylight Saving Time ends on Sunday, 30. March 2025, at 1:00 am, and the time zone reverts from GMT to IST.
The months with the highest humidity are November and December, with an average relative humidity of 90%.
The month with the most rainfall in Shannon is December, when the rain falls for 16.1 days and typically aggregates up to 56mm (2.2") of precipitation.
December is the month with the most snowfall. Snow falls for 0.6 days and accumulates 21mm (0.83") of snow.
The month with the shortest days in Shannon is December, with an average of 7h and 42min of daylight.
Average temperature
Shannon, Ireland
The warmest month (with the highest average high temperature) is July (18°C).
The month with the lowest average high temperature is January (7.8°C).
The month with the highest average low temperature is July (11.1°C).
The coldest months (with the lowest average low temperature) are February and March (2.9°C).
Average pressure
Shannon, Ireland
- Average pressure in January:
1011.4mbar - Average pressure in February:
1011mbar - Average pressure in March:
1014.1mbar - Average pressure in April:
1014.5mbar - Average pressure in May:
1016mbar - Average pressure in June:
1015.5mbar
- Average pressure in July:
1014.2mbar - Average pressure in August:
1012.9mbar - Average pressure in September:
1015.4mbar - Average pressure in October:
1012.2mbar - Average pressure in November:
1008.3mbar - Average pressure in December:
1011mbar
The month with the highest atmospheric pressure is May (1016mbar).
The month with the lowest atmospheric pressure is November (1008.3mbar).
Average wind speed
Shannon, Ireland
- Average wind speed in January:
18.9km/h - Average wind speed in February:
19km/h - Average wind speed in March:
17km/h - Average wind speed in April:
15.1km/h - Average wind speed in May:
15.2km/h - Average wind speed in June:
13.7km/h
- Average wind speed in July:
13.3km/h - Average wind speed in August:
14.3km/h - Average wind speed in September:
14.5km/h - Average wind speed in October:
15.2km/h - Average wind speed in November:
17km/h - Average wind speed in December:
18.8km/h
The windiest month (with the highest average wind speed) is February (19km/h).
The calmest month (with the lowest average wind speed) is July (13.3km/h).
Average humidity
Shannon, Ireland
The months with the highest relative humidity are November and December (90%).
The month with the lowest relative humidity is April (84%).
Average rainfall
Shannon, Ireland
The wettest month (with the highest rainfall) is December (56mm).
The driest month (with the least rainfall) is September (33mm).
Average rainfall days
Shannon, Ireland
- Average rainfall days in January:
16.9 days - Average rainfall days in February:
14.8 days - Average rainfall days in March:
15.1 days - Average rainfall days in April:
16.3 days - Average rainfall days in May:
18.8 days - Average rainfall days in June:
18.6 days
- Average rainfall days in July:
20.3 days - Average rainfall days in August:
20.4 days - Average rainfall days in September:
14.9 days - Average rainfall days in October:
16.1 days - Average rainfall days in November:
16.3 days - Average rainfall days in December:
16.1 days
The month with the highest number of rainy days is August (20.4 days).
The month with the least rainy days is February (14.8 days).
Average snowfall
Shannon, Ireland
The month with the highest snowfall is December (21mm).
The months with the least snowfall are April, May, June, July, August, September, October and November (0mm).
Average snowfall days
Shannon, Ireland
- Average snowfall days in January:
0.8 days - Average snowfall days in February:
0.9 days - Average snowfall days in March:
0.8 days - Average snowfall days in April:
0.1 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 days - Average snowfall days in December:
0.6 days
The month with the highest number of snowfall days is February (0.9 days).
The months with the least snowfall days are May, June, July, August, September, October and November (0 days).
Average sea temperature
Shannon, Ireland
The best month for swimming (with the highest average sea temperature) is August (15.8°C).
The coldest month (with the lowest average sea temperature) is March (9.4°C).
Average daylight / Average sunshine
Shannon, Ireland
- Average daylight in January:
8h and 18min - Average daylight in February:
9h and 54min - Average daylight in March:
11h and 54min - Average daylight in April:
14h and 0min - Average daylight in May:
15h and 48min - Average daylight in June:
16h and 48min
- Average daylight in July:
16h and 18min - Average daylight in August:
14h and 42min - Average daylight in September:
12h and 42min - Average daylight in October:
10h and 36min - Average daylight in November:
8h and 42min - Average daylight in December:
7h and 42min
The month with the longest days is June (Average daylight: 16h and 48min).
The month with the shortest days is December (Average daylight: 7h and 42min).
- Average sunshine in January:
4h and 0min - Average sunshine in February:
4h and 6min - Average sunshine in March:
5h and 0min - Average sunshine in April:
6h and 30min - Average sunshine in May:
6h and 6min - Average sunshine in June:
7h and 18min
- Average sunshine in July:
5h and 54min - Average sunshine in August:
5h and 54min - Average sunshine in September:
5h and 36min - Average sunshine in October:
4h and 18min - Average sunshine in November:
4h and 6min - Average sunshine in December:
4h and 0min
The month with the most sunshine is June (Average sunshine: 7h and 18min).
The months with the least sunshine are January and December (Average sunshine: 4h and 0min).
Average sunshine days
Shannon, Ireland
- Average sunshine days in January:
11.3 days - Average sunshine days in February:
10.8 days - Average sunshine days in March:
11.8 days - Average sunshine days in April:
9.7 days - Average sunshine days in May:
8 days - Average sunshine days in June:
8.1 days
- Average sunshine days in July:
7.6 days - Average sunshine days in August:
8 days - Average sunshine days in September:
11.4 days - Average sunshine days in October:
11.2 days - Average sunshine days in November:
11.5 days - Average sunshine days in December:
12.6 days
The month with the most sunshine days is December (12.6 days).
The month with the least sunshine days is July (7.6 days).
Average UV index
Shannon, Ireland
The months with the highest UV index are May and June (UV index 4).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover
Shannon, Ireland
The month with the most cloud cover is July (Cloud cover 67).
The month with the least cloud cover is April (Cloud cover 56).
Average visibility
Shannon, Ireland
The months with the highest visibility are January, February, March, April, November and December (9km).
The months with the lowest visibility are May, June, July, August, September and October (8km).
