Last updated: March 17, 2025
In December, Merthyr Mawr, United Kingdom, experiences a chilly climate characterized by a maximum temperature of 13°C (55°F) and an average of 7°C (45°F), dipping to a minimum of -2°C (29°F) at night. The month is notably wet, with precipitation totaling 144 mm (5.7 in) spread across approximately 18 days, resulting in a humid atmosphere with levels around 89%. Residents and visitors alike can expect damp weather, necessitating warm clothing and waterproof gear while exploring this picturesque region.
As winter settles in, December temperatures in Merthyr Mawr reveal a distinct chill, with minimums averaging around -2°C (29°F). The month sees an average temperature of 7°C (45°F), offering a noticeable drop from the milder conditions of autumn. As the year winds down, maximum temperatures hover at 13°C (55°F), showcasing the typical transition to colder weather. Interestingly, December's temperatures remain consistent with November's, emphasizing the gradual onset of winter in this picturesque part of the United Kingdom. The crispness of the air invites cozy gatherings and the scenic beauty of the surrounding landscapes, making it a month perfect for reflecting on the year gone by.
In December, Merthyr Mawr experiences a significant jump in precipitation, with 144 mm (5.7 in) of rainfall recorded over 18 days. This marks one of the highest monthly totals of the year, trailing only behind the wetter months of October and November. The consistency of rainfall during this time suggests a shift into a wetter winter pattern, as December stands out for its extended stretch of precipitation days. Compared to the relatively drier spring months, December's increased moisture not only underscores the season's chill but also highlights the diverse weather that characterizes this beautiful region of the United Kingdom. As the year closes, residents can anticipate the lush landscapes that follow this seasonal feast of rainfall.
In December, Merthyr Mawr experiences a notable humidity level of 89%, which maintains the trend from the preceding months, particularly October (also at 89%) and November (90%). This late autumn and early winter period showcases consistently high humidity, with January and February mirroring December’s levels at 88%. Interestingly, humidity levels generally peak toward the end of the year, tapering off to a low of 70% in the summer months. As the year progresses, humidity gradually decreases from a high of 90% in November to December's slightly lower figure, reflecting the seasonal shifts that characterize this picturesque region in the United Kingdom.
As December rolls in, Merthyr Mawr, United Kingdom, experiences a return to a low UV Index of 1, signaling a safe respite from the stronger sun exposure seen in the previous months. This steady drop in UV intensity marks a notable trend as the year progresses from the summer peaks of 8 in June and July, where burn times shrink to just 15 minutes, to the winter months, where one can comfortably enjoy 45 minutes of sun without risk of burning. The transition from autumn to winter is gentle but evident, highlighted by the moderate levels in March and October that serve as reminders of the changing seasons. For more detailed insights, visit Merthyr Mawr UV Index.
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In Merthyr Mawr, December ushers in a cozy retreat from the year’s sun-soaked splendor, contributing just 104 hours of sunshine to the annual tally. This marks a notable decrease from the vibrant 410 hours experienced in the height of July, showcasing the stark contrast between the summer and winter months. As autumn wanes, December's hours dip further from November's 128 hours, signaling the onset of winter's embrace. While this time may be draped in clouds, the fleeting sunshine serves as a gentle reminder of the vibrant warmth that will return with spring’s arrival. The gradual decline in daylight hours, especially in December, highlights the seasonal rhythm, where each month tells its own story—a journey from the luminous brightness of late spring to the tranquil introspection of winter.
In December, the likelihood of encountering sunny weather in Merthyr Mawr, United Kingdom, hovers around 20%, marking one of the lowest probabilities of the year. As the temperatures dip and winter sets in, residents can expect more overcast skies and frequent rain. This trend is consistent with the overall pattern observed throughout the colder months, where both October and January also reflect similarly low chances of sunshine at 21% and 22%, respectively. Interestingly, this trend contrasts sharply with the sunnier days that spring brings, particularly in April, when the likelihood soars to 54%. Thus, anyone hoping for December sun may need to temper their expectations and prepare for the typical chill and cloud.
In Merthyr Mawr, United Kingdom, the pattern of daylight throughout the year reveals a rhythmic ebb and flow, with December offering the shortest days at just 7 hours of daylight. As winter settles in, daylight reaches its annual low, contrasting sharply with the vibrant 16 hours enjoyed in the peak of summer months, specifically June and July. This seasonal cycle showcases a gradual increase in daylight from the depths of winter through the spring, culminating in the lush brightness of summer. As the year winds down, November and December provide a stark reminder of winter’s embrace, with daylight dwindling to a mere flicker, but the promise of lengthening days looms just around the corner in January. The gentle transition from the dark days of winter toward the lengthening light of spring creates a captivating rhythm that is as predictable as it is enchanting.
As December sweeps into Merthyr Mawr, the winds begin to pick up, averaging 5.7 m/s (13 mph), a noticeable rise from the slightly calmer months preceding it. Throughout the year, wind speeds oscillate, with a gentle peak in February at 6.0 m/s (13 mph), followed by a gradual dip in the warmer months of spring and summer. However, as autumn gives way to winter, the winds regain their strength, hinting at the brisk charm of December. This month showcases a shift back to a lively briskness, reminding residents and visitors alike of the invigorating nature of the Welsh landscape during this time of year. The increase in wind speed not only sets the stage for the season's festivities but also invigorates the stunning natural beauty surrounding this picturesque locale.
The weather in Merthyr Mawr changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Merthyr Mawr and find detailed weather information for every month.
In comparing the weather between December and January, we notice some notable differences. December typically experiences slightly warmer average temperatures, with a minimum of -2°C (29°F) and a maximum of 13°C (55°F), while January sees a minimum of -3°C (28°F) and a comparable maximum of 13°C (56°F). Precipitation levels are higher in December at 144 mm (5.7 in) over 18 days, compared to January's 83 mm (3.3 in) across 12 days. Additionally, humidity remains fairly consistent, with December at 89% and January at 88%. For a more detailed look at January weather conditions, you can visit Merthyr Mawr weather in January.
December and February weather have several similarities and differences worth noting. In December, temperatures range from a minimum of -2°C (29°F) to a maximum of 13°C (55°F), with an average of 7°C (45°F). This month experiences more precipitation at 144 mm (5.7 in) over 18 days, contributing to an average humidity of 89%. In contrast, February showcases slightly cooler temperatures, with a minimum of -3°C (26°F) and a maximum of 15°C (59°F), resulting in a slightly lower average of 6°C (44°F). February also sees reduced precipitation, totaling 111 mm (4.4 in) across 15 days, with humidity at 88%. Overall, while both months share chilly conditions and high humidity, December tends to be wetter and slightly milder compared to February. For more details, you can check the Merthyr Mawr weather in February.
In December, the weather is colder, with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 13°C (55°F) and an average of 7°C (45°F). It is characterized by higher precipitation levels, totaling 144 mm (5.7 in) over 18 days, and high humidity at 89%. In comparison, March sees slightly colder minimum temperatures at -5°C (23°F), but a significant increase in maximum temperatures, reaching up to 18°C (64°F), while maintaining the same average of 7°C (45°F). Precipitation in March decreases to 101 mm (4.0 in) over 17 days, with a slightly lower humidity of 86%. For more detailed insights into the weather, you can check Merthyr Mawr weather in March.
December and April present quite contrasting weather patterns. In December, temperatures typically range from a chilly -2°C (29°F) to a maximum of 13°C (55°F), with an average of 7°C (45°F). This month also sees significant precipitation, averaging 144 mm (5.7 in) over 18 days, and a high humidity level of 89%. In contrast, April experiences milder temperatures, with a minimum of -1°C (30°F) and a maximum of 20°C (68°F), resulting in an average of 9°C (49°F). Precipitation is notably lighter in April, totaling 56 mm (2.2 in) across 10 days, and the humidity decreases slightly to 84%. For more detailed information, you can check Merthyr Mawr weather in April.
December and May present contrasting weather patterns in Merthyr Mawr. In December, temperatures typically range from a chilly -2°C (29°F) to a mild 13°C (55°F), with an average of 7°C (45°F). This month also sees significant precipitation, totaling 144 mm (5.7 in) over 18 days, accompanied by high humidity levels averaging 89%. In stark contrast, May offers a much warmer climate, with temperatures between 2°C (36°F) and 24°C (75°F) and an average of 12°C (54°F). Rainfall decreases to 80 mm (3.2 in) spread over 12 days, and the humidity drops to a more comfortable 80%. For more detailed information, check out Merthyr Mawr weather in May.
December and June exhibit contrasting weather patterns, reflecting the seasonal shift. In December, temperatures range from a chilly -2°C (29°F) at night to a mild 13°C (55°F) during the day, with frequent precipitation totaling 144 mm (5.7 inches) across 18 days and high humidity at 89%. In contrast, June brings warmer conditions, with temperatures ranging from a minimum of 7°C (45°F) to a pleasant maximum of 27°C (81°F). Although June experiences less precipitation at 85 mm (3.3 inches) over 13 days, humidity is still notable at 80%. For a detailed look at June weather in this area, check out Merthyr Mawr weather in June.
December and July present stark contrasts in weather at Merthyr Mawr. In December, temperatures range from a chilly -2°C (29°F) at night, averaging around 7°C (45°F) during the day, and peaking at 13°C (55°F). The month is also characterized by high humidity at 89% and significant precipitation, totaling 144 mm (5.7 inches) over 18 days. In contrast, July offers a much milder climate with temperatures starting at a minimum of 9°C (48°F), averaging 17°C (63°F), and soaring to a maximum of 27°C (81°F). The summer month is drier, with only 86 mm (3.4 inches) of rain spread over 12 days and a lower humidity level of 70%. For more information, visit Merthyr Mawr weather in July.
December and August present contrasting weather patterns, reflecting the shift from winter to summer. In December, temperatures range from a chilly -2°C (29°F) at night to a mild 13°C (55°F) during the day, with an average of 7°C (45°F). The month experiences significant precipitation, with an average of 144 mm (5.7 in) of rainfall spread over 18 days, contributing to a high humidity level of 89%. In stark contrast, August offers a much warmer climate, with temperatures ranging from a minimum of 9°C (48°F) at night to a maximum of 28°C (82°F) during the day, resulting in a more pleasant average of 16°C (62°F). Precipitation also decreases to 106 mm (4.2 in) over 16 days, accompanied by a lower humidity of 73%. For those interested in the specifics of August weather, further details can be found at Merthyr Mawr weather in August.
When comparing the weather in December and September, December is notably colder, with average temperatures ranging from a minimum of -2°C (29°F) to a maximum of 13°C (55°F). In contrast, September enjoys milder conditions, with temperatures averaging between 5°C (41°F) and 27°C (80°F). Additionally, December experiences significantly more precipitation, totaling 144 mm (5.7 in) over 18 days, while September sees less rain at 92 mm (3.6 in) over 12 days. Humidity levels are also higher in December at 89%, compared to 79% in September. For more details about the weather specific to September, you can check Merthyr Mawr weather in September.
In comparing December and October weather, December tends to be significantly cooler, with average temperatures ranging from a minimum of -2°C (29°F) to a maximum of 13°C (55°F), compared to October's more moderate range of 1°C (33°F) to 21°C (70°F). While both months experience a similar amount of precipitation, with December recording 144 mm (5.7 in) and October slightly higher at 146 mm (5.7 in), December has more rainy days, averaging 18 days compared to October's 17 days. Additionally, humidity remains consistent at 89% for both months, emphasizing the damp atmosphere common during this time of year. For a closer look at October weather specifics, visit Merthyr Mawr weather in October.
December weather tends to be colder and wetter compared to November. While the average temperature in December hovers around 7°C (45°F) with minimums dropping to -2°C (29°F), November is slightly warmer, averaging 9°C (48°F) and a minimum of -1°C (31°F). Additionally, December sees more precipitation, totaling 144 mm (5.7 in) over 18 days, compared to November's 111 mm (4.4 in) across 16 days. Humidity levels remain quite similar, with December at 89% and November at 90%. For more specific insights about November's weather, visit Merthyr Mawr weather in November.
As December ushers in winter, Merthyr Mawr experiences a notable shift in weather patterns compared to other months. The temperature drops, with chilly nights reaching as low as -2°C, while the average remains a brisk 7°C. This month also brings a significant increase in precipitation, with rainfall occurring on about half the days, resulting in a humid atmosphere with levels around 89%. The combination of colder temperatures and higher moisture makes December distinctly crisp and damp, setting it apart from the milder months of autumn and spring. For more on seasonal variations, explore Merthyr Mawr Climate.