Letterkenny is a city of approximately 19,300 people in Ulster, Ireland. Located in the GMT/IST time zone at 55°N latitude.
In 2025, Letterkenny recorded an average annual temperature of 50°F. The hottest temperatures reached 83°F in July; the coolest were 22°F in January. Total precipitation for the year was 44 inches, with the wettest month being June. Snowfall for the year totaled approximately 3 inches.
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