Last updated: March 17, 2025
Shannon, Ireland, experiences a diverse climate in September, characterized by a maximum temperature of 26°C (80°F) and an average of 13°C (56°F), with lows dipping to 1°C (35°F). The month sees considerable rainfall, with 91 mm (3.6 in) of precipitation spread over 16 days, leading to an overall humidity level of 88%. This combination of warm days, chilly nights, and frequent showers creates a unique atmosphere, inviting both residents and visitors to embrace the beautiful unpredictability of Ireland's early autumn.
In September, Shannon, Ireland, experiences a delightful transition into autumn, with temperatures reflecting a balance of summer's warmth and the crispness of fall. The minimum temperature is around 1°C (35°F), while the average settles at a comfortable 13°C (56°F). Days can still be quite pleasant, with an impressive maximum reaching 26°C (80°F), making it one of the warmest months of the year. As the month progresses, you may notice a gradual cool-down from the warmer summer highs, foreshadowing the chilling temperatures to come in October. Overall, September in Shannon offers a charming climate perfect for exploring the scenic beauty of Ireland as the leaves begin to change.
September in Shannon, Ireland, typically experiences a moderate level of precipitation, with an average of 91 mm (3.6 inches) spread across roughly 16 days. This follows an increased rainfall trend from August, which recorded 126 mm (5.0 inches) over 19 days, signaling the tail end of summer's moisture. As autumn sets in, the sporadic showers in September prepare the landscape for the wetter months ahead, as both October and November see higher averages of 106 mm (4.2 inches) and 98 mm (3.8 inches) respectively. This pattern highlights a shift from the summer's intensity to a more consistent fall rain, making September a transition month with its own unique charm amidst the changing seasons.
In Shannon, Ireland, September ushers in a return to higher humidity levels, mirroring the consistent patterns observed in the earlier months of the year with a recorded 88%. This is notably similar to the humidity in January and February, suggesting that the late summer warmth may retain some of the moisture in the air. As the seasons transition into autumn, humidity gradually rises, peaking in November at 92%, before tapering off in the winter months. Overall, September serves as a bridge between the milder summer and the cooler, wetter autumn, maintaining the lush, green landscapes that Ireland is renowned for.
In September, the UV Index in Shannon, Ireland, reflects a transition as summer gives way to autumn, registering at 5, which falls into the moderate exposure category. This marks a slight dip from the peak summer months of June and July, where the index soared to a striking 8, but remains higher than earlier in the year. As days shorten and temperatures cool, the burn time stretches back to 30 minutes, allowing for more time outdoors without the immediate risk of sunburn. It's essential to stay aware of these fluctuations in UV levels, as even with a moderate index, protective measures can enhance your skin's safety when enjoying the vibrant early autumn scenery. For more details, check out the Shannon UV Index.
UV Risk Categories
As September unfolds in Shannon, Ireland, the charm of summer lingers with 277 hours of sunshine, making it a delightful month to savor the last warm rays before autumn's embrace. This notable total follows a vibrant progression from the spring's 179 hours in March to a striking 382 hours in May, reflecting a steady ascent in daylight that peaks during the summer months. Although September’s sunshine is less abundant than the highs of July and August, it still offers a captivating tapestry of light that colors the early days of fall. The gradual decrease in sunlight toward the year’s end, with 220 hours in October and just 95 hours in December, underscores the bittersweet transition from the vibrant warmth of summer to the more subdued tones of winter, inviting both reflection and appreciation of the seasonal shifts.
In Shannon, Ireland, the likelihood of sunny weather takes a noticeable dip in September, with only a 16% chance of sunshine gracing the skies. This marks the close of summer, leading into the more unpredictable autumn months. As the year progresses, the trend shows that the sun is increasingly elusive after the more promising spring months, particularly April, where the possibility of clear skies peaks at 45%. With September landing among the lower end of the spectrum, it is clear that those hoping for bright days should prepare for a shift towards the moody weather typical of the Irish climate, reinforcing the need for layers and umbrellas as the days grow shorter.
As September unfolds in Shannon, Ireland, the daylight begins to wane, with the sun shining for approximately 12 hours each day. This marks a gentle decline from the vibrant 16 hours of daylight experienced in June and July, as summer gradually hands over the reins to autumn. Following the peak of 15 hours in May, September sees a notable shift as the days shorten, transitioning towards the 10 hours of October and further into the darker months. The rhythm of daylight reflects the changing seasons, inviting a blend of both the lingering warmth of late summer and the crisp promise of fall.
In Shannon, Ireland, the winds of September whisper at an average speed of 3.1 m/s (7 mph), showing a gentle decline from the summer breezes. This month, nestled between the warmer air of August and the brisk autumn winds that October brings, offers a tranquil shift in the natural rhythm of the seasons. Notably, wind speeds dipped throughout the summer, reaching their lowest in July at 2.6 m/s (6 mph) before making a slight rebound in the fall. As the year progresses, the embrace of autumn is felt, with winds picking up slightly but remaining dependable and mild, hinting at the changing landscape ahead.
The weather in Shannon changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Shannon and find detailed weather information for every month.
In September, the weather is generally milder with temperatures ranging from a minimum of 1°C (35°F) to a maximum of 26°C (80°F), averaging around 13°C (56°F). With a total precipitation of 91 mm (3.6 in) over 16 days, the month experiences fairly consistent rainfall, accompanied by high humidity levels of 88%. In contrast, January sees cooler temperatures, with a minimum of -5°C (24°F) and a maximum of 14°C (58°F), averaging just 6°C (43°F). Although the precipitation in January is slightly lower at 75 mm (3.0 in) over 13 days, the humidity remains unchanged at 88%, creating a distinctly chillier atmosphere compared to September. For more specific details about January weather, you can check out Shannon weather in January.
In September, the weather is generally milder, with average temperatures ranging from a minimum of 1°C (35°F) to a maximum of 26°C (80°F). During this month, the region experiences about 91 mm (3.6 in) of precipitation over 16 days, with humidity consistently high at 88%. In contrast, February presents a colder atmosphere, where temperatures range from a low of -3°C (27°F) to a high of 15°C (60°F). February also has a slightly higher average precipitation of 121 mm (4.8 in) spread across 18 days, while maintaining the same humidity level of 88%. For more detailed information, you can check Shannon weather in February.
September and March present contrasting weather patterns. September typically boasts milder temperatures, ranging from a minimum of 1°C (35°F) to a maximum of 26°C (80°F), with an average of 13°C (56°F). In contrast, March is cooler, with temperatures stretching from -6°C (21°F) to 17°C (63°F) and an average of 7°C (45°F). Both months experience relatively high precipitation, with September receiving 91 mm (3.6 in) over 16 days and March slightly wetter at 105 mm (4.1 in) across 17 days. Humidity is similarly high in both months, at 88% in September and 87% in March. For more detailed insights, check out Shannon weather in March.
September and April present distinct weather contrasts. In September, temperatures range from a cool 1°C (35°F) to a warm 26°C (80°F), with an average of 13°C (56°F). The month experiences higher precipitation, totaling 91 mm (3.6 in) over 16 days, and a slightly higher humidity of 88%. In contrast, April features cooler temperatures, with a minimum of -2°C (28°F) and a maximum of 21°C (70°F), averaging 9°C (48°F). It also sees less precipitation at 58 mm (2.3 in) spread over 12 days, along with a humidity level of 86%. For more details about April weather, you can check Shannon weather in April.
In comparing the weather between September and May, both months feature mild temperatures, but September tends to be slightly warmer, with an average of 13°C (56°F) compared to May's 12°C (53°F). The maximum temperatures also show a slight increase in September, reaching up to 26°C (80°F), while May peaks at 25°C (77°F). However, September experiences more precipitation, with 91 mm (3.6 in) over 16 days, compared to May's 72 mm (2.8 in) over 13 days. Additionally, September has a higher humidity level at 88%, compared to May's 83%. For more specific insights on weather conditions, you can check Shannon weather in May.
In comparing the weather between September and June, we observe notable differences in temperature and precipitation. September experiences cooler averages, with temperatures ranging from a minimum of 1°C (35°F) to a maximum of 26°C (80°F), while June sees warmer conditions, with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 30°C (86°F). Although September has a higher average rainfall of 91 mm (3.6 in) over 16 days compared to June's 71 mm (2.8 in) over 15 days, the humidity levels are also slightly higher in September at 88% versus June's 83%. For more detailed information about the weather in June, you can visit Shannon weather in June.
In comparing the weather between July and September, we see notable differences in temperature and precipitation. July typically experiences milder temperatures, with a minimum of 7°C (44°F) and a maximum reaching 29°C (84°F), resulting in an average of 16°C (61°F). The humidity is slightly lower at 85%, and there are fewer rainy days, with total precipitation at 79 mm (3.1 in) over 13 days. In contrast, September brings cooler conditions with a minimum temperature dropping to 1°C (35°F) and a maximum of 26°C (80°F), averaging 13°C (56°F). The month is also rainier, receiving 91 mm (3.6 in) of precipitation across 16 days and a higher humidity level at 88%. For a closer look at July's weather specifics, visit Shannon weather in July.
In comparing the weather of September and August, September presents a cooler temperature range with a minimum of 1°C (35°F) and an average of 13°C (56°F), while August enjoys milder conditions with a minimum of 6°C (43°F) and an average of 15°C (59°F). Both months experience significant precipitation, but August sees a higher amount at 126 mm (5.0 in) over 19 days compared to September's 91 mm (3.6 in) over 16 days. Humidity levels remain relatively high in both months, with September slightly more humid at 88% versus August's 85%. For a more detailed look at the weather patterns, you can visit Shannon weather in August.
September and October exhibit notable differences in weather. In September, temperatures range from a minimum of 1°C (35°F) to a maximum of 26°C (80°F), with an average of 13°C (56°F). This month experiences 91 mm (3.6 in) of precipitation over 16 days and a humidity level of 88%. Conversely, October sees a slight drop in temperatures, with a minimum of 0°C (32°F), an average of 11°C (51°F), and a maximum of 19°C (67°F). The precipitation increases to 106 mm (4.2 in) while maintaining the same frequency of rain on 16 days, and the humidity rises to 91%. For more details, check out Shannon weather in October.
In September, the weather features a wider temperature range with a minimum of 1°C (35°F), an average of 13°C (56°F), and a maximum of 26°C (80°F), creating a generally mild atmosphere. The month sees 91 mm (3.6 in) of precipitation over 16 days, with humidity at a relatively high 88%. In contrast, November ushers in cooler temperatures, dropping to a minimum of -2°C (28°F), an average of 8°C (46°F), and a maximum of 16°C (61°F). Rainfall slightly increases to 98 mm (3.8 in) over the same number of days, with humidity rising to 92%. For a detailed look at November weather specifics, you can refer to Shannon weather in November.
When comparing the weather in September and December, we observe a significant shift in temperatures and conditions. September sees milder temperatures, with a minimum of 1°C (35°F) and an average high of 26°C (80°F), making it a much warmer month overall. In contrast, December experiences cooler temperatures, with a minimum of -3°C (27°F) and an average high of just 14°C (57°F).
Precipitation also increases in December, totaling 123 mm (4.8 in) over 18 days, compared to September's 91 mm (3.6 in) over 16 days. Both months exhibit high humidity levels, with September at 88% and December slightly higher at 89%. For a detailed overview of weather patterns specific to December, you can check Shannon weather in December.
September in Shannon marks a transition as the summer warmth fades, giving way to cooler temperatures and a notable increase in precipitation. With an average temperature settling around a refreshing 13°C, the month feels distinctly different from the balmy summer months. The high humidity, often reaching 88%, adds to the briskness, while the 16 days of rain remind us that autumn is just around the corner. This combination of cooler air and frequent showers creates a unique atmosphere, inviting visitors to experience the lush landscapes that thrive in these conditions. For a deeper dive into what to expect weather-wise throughout the year, explore Shannon Climate.