Letterkenny Weather in January
January in Letterkenny averages 9°C (48°F) during the day and 3°C (37°F) at night. Quite a bit of rainfall is typical this month, with around 115 mm (4.5 in) on average. An umbrella is a good idea.
Rainfall in Letterkenny in January
Looking at the last 30 years, the data shows about 24 days with rain, averaging 115 mm (4.5 in) for the month. Expect frequent rainfall this month, and not just light drizzle. When it rains, it tends to come down hard.
Temperature in Letterkenny in January
Daytime highs in Letterkenny in January reach 9°C (48°F), with nights around 3°C (37°F). January marks the winter season. Expect a cold feel throughout the day, not just in the mornings and evenings. Warm layers are essential. Nights fall to 3°C (37°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep. The month is typically the coldest, so be sure to prepare by packing plenty of warm clothing.
Sunshine in Letterkenny in January
The month has fewer sunny days, with around 50 hours of sunshine.If you're looking for dry conditions and comfortable temperatures, January may not be the ideal month to visit Letterkenny. Our weather planner can help you explore destinations with more pleasant weather conditions.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Ireland, check out our Letterkenny's climate page.
Letterkenny Temperature in January
Daily Historical Temperatures
51-year average (1976-2026)
Based on our historical records, temperatures in Letterkenny typically stay consistent throughout January, with daily highs averaging around 9°C (48°F). Nights are cold, with lows around 3°C (37°F).
Average temperatures in January
Daily Historical Precipitation
51-year average (1976-2026)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in January
Historical weather for Letterkenny in January
Browse day-by-day weather records for Letterkenny spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Letterkenny historical weather extremes in January
Our historical data for Letterkenny spans 2000 to 2025, revealing these weather extremes.
- Letterkenny recorded its highest January temperature of 15°C (59°F) on January 9, 2007.
- On January 8, 2010, Letterkenny saw its coldest January day with temperatures maxing out at -2°C (28°F).
- Nighttime temperatures dropped to -9°C (16°F) on January 9, 2010, marking the coldest January night on record.
- The wettest day in January Letterkenny was on January 21, 2008 with 26 mm (1 in) of precipitation.
Best Places in Ireland in January
Find out more about the weather in Ireland and which places have the best travel conditions in this month. See all of Ireland in January →
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What to Wear in Letterkenny in January
Dress warmly and in layers for your trip to Letterkenny in January. A good base layer system works wonders. Start with good thermal underwear, add something warm like a fleece sweater, then finish with a waterproof jacket on top. Expect heavy rainfall, so bring good rain protection and waterproof bags. Sunglasses aren't essential this month, though you might want them for the occasional bright moment.What To Do in Letterkenny in January
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Ireland, check out our Letterkenny's climate page.
See the full Letterkenny climate overview or explore weather in Ireland.