Current Conditions

Merrimack, New Hampshire

46°F8°C

Clear

Wind

NNE 6 mph10 km/h

Humidity

86%

Cloud Cover

56%

As of Wednesday, September 23, 2026 at 1:38 AM EDT

Today's Outlook

Day

Mostly clear and mild, with a high of 64°F18°C and morning low of 50°F10°C. Breezy from the ENE at 9 to 11 mph15 to 17 km/h. Dry air.

Night

Partly cloudy, with a low around 45°F7°C. Breezy from the NNE at 6 to 8 mph9 to 12 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 64°F18°C	Low 45°F7°CFeels 41°F5°C	Precip 0 in0 mm—	Cloud 27%	Wind NE 7 mph12 km/h	Wednesday: Mostly clear and mild, with a high of 64°F18°C and morning low of 50°F10°C. Breezy from the ENE at 9 to 11 mph15 to 17 km/h. Dry air. Wednesday Night: Partly cloudy, with a low around 45°F7°C. Breezy from the NNE at 6 to 8 mph9 to 12 km/h.
Clear	High 66°F19°C	Low 44°F6°CFeels 39°F4°C	Precip 0 in0 mm—	Cloud 30%	Wind NE 7 mph11 km/h	Thursday: Mostly clear and mild, with a high of 66°F19°C and morning low of 48°F9°C. Breezy from the NE at 8 to 9 mph13 to 15 km/h. Dry air. Thursday Night: Partly cloudy, with a low around 44°F6°C. Breezy from the NNE at 6 to 7 mph9 to 11 km/h.
Light Rain	High 67°F20°C	Low 48°F9°CFeels 44°F7°C	Precip 0.07 in1.7 mm33%	Cloud 89%	Wind NNE 10 mph16 km/h	Friday: Overcast and mild, with a high of 67°F20°C and morning low of 52°F11°C. Breezy from the NE at 10 to 12 mph17 to 19 km/h. 17% chance of drizzle in the afternoon. Dry air. Friday Night: Overcast, with a low around 48°F9°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 33% chance of light rain in the evening.
Rain	High 61°F16°C	Low 56°F13°C	Precip 0.59 in14.9 mm79%	Cloud 94%	Wind NNE 13 mph21 km/h	Saturday: Overcast and mild, with a high of 61°F16°C. Breezy from the NNE at 13 mph21 km/h. 71% chance of light rain throughout the day. Dry air. Saturday Night: Overcast, with a low around 56°F13°C. Breezy from the NNE at 13 to 14 mph20 to 22 km/h. 79% chance of rain throughout the night.
Rain	High 58°F15°C	Low 57°F14°C	Precip 0.87 in22.1 mm94%	Cloud 100%	Wind NE 13 mph21 km/h	Sunday: Overcast and mild, with a high of 58°F15°C. Breezy from the NE at 13 to 14 mph22 to 23 km/h. 94% chance of rain throughout the day. Sunday Night: Overcast, with a low around 57°F14°C. Breezy from the NE at 13 to 14 mph21 to 23 km/h. 92% chance of rain throughout the night.
Light Rain	High 59°F15°C	Low 56°F13°C	Precip 0.39 in10 mm87%	Cloud 98%	Wind NNE 8 mph13 km/h	Monday: Overcast and mild, with a high of 59°F15°C. Breezy from the NNE at 8 to 9 mph13 to 14 km/h. 76% chance of light rain throughout the day. Monday Night: Overcast, with a low around 56°F14°C. Breezy from the NNE at 8 to 10 mph13 to 17 km/h. 87% chance of light rain throughout the night.
Drizzle	High 66°F19°C	Low 57°F14°C	Precip 0.05 in1.2 mm30%	Cloud 80%	Wind NW 5 mph8 km/h	Tuesday: Overcast and mild, with a high of 66°F19°C and morning low of 58°F14°C. Light wind from the NW around 5 mph8 km/h. 15% chance of drizzle throughout the day. Tuesday Night: Mostly cloudy, with a low around 57°F14°C. Light wind from the NW around 5 mph8 km/h. 30% chance of drizzle overnight.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	64°F18°C	45°F7°C Feels 41°F5°C	0 in0 mm· —	27%	Clear	NE 7 mph12 km/h
DayMostly clear and mild, with a high of 64°F18°C and morning low of 50°F10°C. Breezy from the ENE at 9 to 11 mph15 to 17 km/h. Dry air. NightPartly cloudy, with a low around 45°F7°C. Breezy from the NNE at 6 to 8 mph9 to 12 km/h.
	ThursdaySep 24	66°F19°C	44°F6°C Feels 39°F4°C	0 in0 mm· —	30%	Clear	NE 7 mph11 km/h
DayMostly clear and mild, with a high of 66°F19°C and morning low of 48°F9°C. Breezy from the NE at 8 to 9 mph13 to 15 km/h. Dry air. NightPartly cloudy, with a low around 44°F6°C. Breezy from the NNE at 6 to 7 mph9 to 11 km/h.
	FridaySep 25	67°F20°C	48°F9°C Feels 44°F7°C	0.07 in1.7 mm· 33%	89%	Light Rain	NNE 10 mph16 km/h
DayOvercast and mild, with a high of 67°F20°C and morning low of 52°F11°C. Breezy from the NE at 10 to 12 mph17 to 19 km/h. 17% chance of drizzle in the afternoon. Dry air. NightOvercast, with a low around 48°F9°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 33% chance of light rain in the evening.
	SaturdaySep 26	61°F16°C	56°F13°C	0.59 in14.9 mm· 79%	94%	Rain	NNE 13 mph21 km/h
DayOvercast and mild, with a high of 61°F16°C. Breezy from the NNE at 13 mph21 km/h. 71% chance of light rain throughout the day. Dry air. NightOvercast, with a low around 56°F13°C. Breezy from the NNE at 13 to 14 mph20 to 22 km/h. 79% chance of rain throughout the night.
	SundaySep 27	58°F15°C	57°F14°C	0.87 in22.1 mm· 94%	100%	Rain	NE 13 mph21 km/h
DayOvercast and mild, with a high of 58°F15°C. Breezy from the NE at 13 to 14 mph22 to 23 km/h. 94% chance of rain throughout the day. NightOvercast, with a low around 57°F14°C. Breezy from the NE at 13 to 14 mph21 to 23 km/h. 92% chance of rain throughout the night.
	MondaySep 28	59°F15°C	56°F13°C	0.39 in10 mm· 87%	98%	Light Rain	NNE 8 mph13 km/h
DayOvercast and mild, with a high of 59°F15°C. Breezy from the NNE at 8 to 9 mph13 to 14 km/h. 76% chance of light rain throughout the day. NightOvercast, with a low around 56°F14°C. Breezy from the NNE at 8 to 10 mph13 to 17 km/h. 87% chance of light rain throughout the night.
	TuesdaySep 29	66°F19°C	57°F14°C	0.05 in1.2 mm· 30%	80%	Drizzle	NW 5 mph8 km/h
DayOvercast and mild, with a high of 66°F19°C and morning low of 58°F14°C. Light wind from the NW around 5 mph8 km/h. 15% chance of drizzle throughout the day. NightMostly cloudy, with a low around 57°F14°C. Light wind from the NW around 5 mph8 km/h. 30% chance of drizzle overnight.
	WednesdaySep 30	71°F21°C	56°F13°C	0.01 in0.2 mm· 5%	65%	Partly Cloudy	SW 4 mph7 km/h
DayMostly cloudy and warm, with a high of 71°F21°C and morning low of 57°F14°C. Light wind from the SW around 4 mph6 km/h. NightMostly cloudy, with a low around 56°F13°C. Light wind from the SW around 5 mph7 km/h.
	ThursdayOct 1	72°F22°C	58°F14°C	0.1 in2.6 mm· 20%	71%	Light Rain	SSW 6 mph10 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 60°F15°C. Breezy from the SSW at 7 to 8 mph11 to 12 km/h. 20% chance of light rain throughout the day. NightMostly cloudy, with a low around 58°F14°C. Breezy from the SSW at 6 to 7 mph10 to 12 km/h. 19% chance of drizzle throughout the night.
	FridayOct 2	70°F21°C	58°F15°C	0.16 in4 mm· 18%	60%	Showers	WSW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the W at 7 to 8 mph11 to 12 km/h. 18% chance of showers throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the WSW at 7 mph11 km/h. 16% chance of showers throughout the night.
	SaturdayOct 3	69°F20°C	54°F12°C	0.1 in2.5 mm· 13%	58%	Drizzle	W 6 mph10 km/h
DayMostly cloudy and warm, with a high of 69°F20°C and morning low of 55°F13°C. Breezy from the W at 7 to 8 mph11 to 12 km/h. 12% chance of drizzle throughout the day. NightMostly cloudy, with a low around 54°F12°C. Light wind from the W around 6 mph10 km/h. 13% chance of drizzle throughout the night.
	SundayOct 4	67°F20°C	53°F12°C	0.15 in3.7 mm· 23%	65%	Showers	SW 6 mph10 km/h
DayMostly cloudy and mild, with a high of 67°F20°C and morning low of 55°F13°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 53°F12°C. Light wind from the WSW around 6 mph10 km/h. 19% chance of showers throughout the night.
	MondayOct 5	66°F19°C	54°F12°C	0.18 in4.6 mm· 27%	68%	Showers	W 7 mph11 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 55°F13°C. Breezy from the W at 7 to 8 mph11 to 12 km/h. 27% chance of light rain throughout the day. NightMostly cloudy, with a low around 54°F12°C. Breezy from the W at 6 to 7 mph10 to 11 km/h. 23% chance of showers throughout the night.
	TuesdayOct 6	64°F18°C	52°F11°C	0.14 in3.5 mm· 21%	55%	Showers	WNW 7 mph11 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 52°F11°C. Breezy from the WNW at 7 to 8 mph11 to 12 km/h. 16% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 52°F11°C. Breezy from the W at 7 mph11 km/h. 21% chance of showers throughout the night.
	WednesdayOct 7	62°F17°C	49°F10°C	0.13 in3.4 mm· 20%	54%	Showers	W 7 mph11 km/h
DayMostly cloudy and mild, with a high of 62°F17°C and morning low of 50°F10°C. Breezy from the W at 7 to 8 mph12 to 13 km/h. 20% chance of showers throughout the day. Dry air. NightPartly cloudy, with a low around 49°F10°C. Breezy from the W at 7 mph11 km/h. 19% chance of showers throughout the night.

Nearby Cities

Bedford6 mi9 km Nashua7 mi11 km Derry8 mi14 km Manchester9 mi15 km Derry Village9 mi15 km Salem16 mi25 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 42.8651°N, 71.4934°W·Elevation: 47m·Timezone: America/New_York·Population: 26,726