Merrimack weather
Best months for weather: May–Sep. Below: today's sky, the hour-by-hour rain chance and the 16-day forecast for Merrimack, New Hampshire, United States.
Best Time to Visit
Peak season May–SepOff season Nov–Mar
Merrimack weather by month
When is the best time to visit Merrimack?
Based on weather alone, the best time to visit Merrimack is May–Sep, according to NASA's 2001–2025 climate averages. Nov–Mar tends to be the least pleasant. Average highs run from -1°C (30°F) in January to 27°C (81°F) in July.
What is the rainiest month in Merrimack?
October is the wettest month, with about 123 mm (4.8 in) of rain on average. January is the driest, with about 73 mm (2.9 in).
What is the hottest month in Merrimack?
July is the warmest, with average highs of 27°C (81°F) and lows of 17°C (62°F). January is the coolest, with highs of -1°C (30°F) and lows of -10°C (15°F).
Does Merrimack have a rainy season?
Not a strong one. No month averages more than 150 mm of rain; the wettest is October at about 123 mm (4.8 in).
Sources: 2001–2025 monthly averages from NASA POWER (MERRA-2 reanalysis), forecast and current conditions from Open-Meteo. Page updated . How we rate months