Merrimack weather in October

In October, Merrimack sees average daytime highs of 61°F and overnight lows near 44°F, with 3.8 in of precipitation across 9.3 wet days and about 10.8 hours of daylight. It is the 6th-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 66°F in the first days to 55°F by the end. The sky is clear or mostly clear about 37% of the time in October, and the air most often feels dry.

Daylight stretches from about 11 h 30 min at the start of October to 10 h 06 min by month's end. Set against the rest of the year, October is Merrimack's 2nd-clearest and 7th-windiest month. For the whole year in context, see Merrimack's year-round climate.

Daytime high
61°
6th warmest
Overnight low
44°
7th coldest
Precipitation
3.8 in
9.3 wet days
Daylight
10 h 48 min
6:07 AM – 4:55 PM
Cloud cover
56%
2nd clearest
Wind
7 mph
7th windiest
Solar energy
2.86 kWh/m²
Travel score
5.1
out of 10

Merrimack is town in New Hampshire, United States.

Founded
1673

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in October

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 66°F in the first days to 55°F by the end.

A typical October day in Merrimack reaches about 61°F in the afternoon and slips back to 44°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 51°F and 72°F. Set against its neighbours, October runs about 12°F cooler than September and about 12°F warmer than November.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
16749
26648
36648
46547
56547
66547
76446
86446
96346
106345
116345
126245
136244
146244
156144
166143
176043
186043
195942
205942
215942
225842
235841
245741
255741
265740
275640
285640
295539
305539
315539

How October really feels in Merrimack

Once humidity and wind are folded in, October averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

October sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Merrimack weather by month

How October compares with the rest of the year at a glance. October is the 6th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan34° / 19°3.19.66.79.20.0
Feb36° / 20°3.08.4610.20.0
Mar44° / 28°4.110.95.411.60.8
Apr57° / 39°3.710.51.513.13.8
May67° / 48°3.210.8014.46.0
Jun77° / 58°3.510.8015.16.5
Jul82° / 64°3.410.3014.86.0
Aug80° / 62°3.49.6013.76.6
Sep73° / 54°3.48012.37.0
Oct61° / 44°3.89.30.310.85.1
Nov49° / 34°3.49.41.49.52.0
Dec39° / 25°4.110.35.58.90.1

Cloud cover in October

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in October.

Beyond those clear spells, partly cloudy skies cover about 14% of October, with mostly cloudy or overcast conditions the remaining 50%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15248
25248
35248
45347
55347
65347
75347
85347
95347
105347
115347
125248
135248
145248
155248
165149
175050
185050
195050
205050
214951
224951
234951
244852
254753
264753
274753
284753
294753
304753
314753

Chance of precipitation in October

Any precipitationSnow

Merrimack gets around 3.8 in of rain and snow over 9.3 wet days in October. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 30% and peaks near 31% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1290
2290
3290
4290
5290
6290
7300
8300
9300
10300
11300
12300
13300
14301
15301
16301
17301
18301
19301
20301
21301
22301
23302
24312
25312
26312
27312
28312
29312
30312
31312

Humidity in October

DryComfortableHumidMuggyOppressiveMiserable

Most of October feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, October lands in the dry band about 90% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
1761473
2771373
3801262
4801262
5821152
6831052
7841042
886941
987841
1088831
1189731
1289731
1390631
1491621
1592521
1692521
1792521
1893520
1993520
2093520
2193520
2293520
2393520
2493520
2595410
2695410
2795410
2895410
2995410
3095410
3195410

Wind in October

Winds average 7 mph in October.

Across October, daily wind ranges from about 7 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257light breeze
267light breeze
277light breeze
287light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in October

DaylightNight

Daylight runs from about 11 h 30 min at the start of October to 10 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over October. Sunrise moves from 5:49 AM to 6:26 AM, and sunset from 5:21 PM to 4:33 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.55:495:21
211.55:505:19
311.45:515:18
411.45:525:16
511.35:535:14
611.35:555:12
711.25:565:10
811.25:575:09
911.15:585:07
1011.15:595:05
1111.06:015:04
1211.06:025:02
1311.06:035:00
1410.96:044:59
1510.96:064:57
1610.86:074:55
1710.86:084:54
1810.76:094:52
1910.76:104:50
2010.66:124:49
2110.66:134:47
2210.56:144:46
2310.56:164:44
2410.46:174:43
2510.46:184:41
2610.36:194:40
2710.36:214:39
2810.36:224:37
2910.26:234:36
3010.26:244:35
3110.16:264:33

Solar energy in October

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in October, about 2.86 kWh/m².

For context, solar energy here swings from a low near 1.58 kWh/m² to a high of 5.88 kWh/m² in July across the year — October's 2.86 kWh/m² falls in the middle.

01234151015202531
Solar energy (kWh/m²)Level
13.4Moderate
23.4Moderate
33.4Moderate
43.3Moderate
53.3Moderate
63.2Moderate
73.2Moderate
83.2Moderate
93.1Moderate
103.1Moderate
113.1Moderate
123.0Moderate
133.0Moderate
143.0Moderate
152.9Moderate
162.9Moderate
172.8Moderate
182.8Moderate
192.8Moderate
202.7Moderate
212.7Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.5Moderate
262.5Moderate
272.5Moderate
282.4Moderate
292.4Moderate
302.4Moderate
312.4Moderate
Planning a trip in October

Hazard calendar for Merrimack

In seasonPeak

In October, Merrimack sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Merrimack sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is October a good time to visit Merrimack?

Our two travel scores rate October for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.1
Sightseeing
6th-best month of the year
1.0
Beach & pool
6th-best month of the year

October is a reasonable time to visit Merrimack for sightseeing.

What to pack for Merrimack in October

From October's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In October, Merrimack sees daytime highs around 61°F and nights near 44°F. Worth packing: a warm layer and rain gear. About 9 days see rain.

a warm layerrain gear

UV index in Merrimack in October

LowModerateHighVery highExtreme

Clear-sky midday UV in October peaks around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Merrimack peaks around July 10 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighHighModerateLowJul 10UV 7Dec 23UV 1
UV index (midday)Level
Jan1Low
Feb3Moderate
Mar4Moderate
Apr5High
May7Very high
Jun7High
Jul7Very high
Aug5Moderate
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Merrimack in October

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where October falls, not just the annual average.

Air quality in Merrimack is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (November, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1715 µg/m³Nov 188 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb13Moderate
Mar13Moderate
Apr13Moderate
May14Moderate
Jun13Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct9Good
Nov8Good
Dec9Good
Location & terrain

Where is Merrimack?

Merrimack sits at 42.9°N, 71.5°W, 154 ft above sea level, in United States. The nearest listed city is Bedford, 5.6 mi away.

Topography around Merrimack

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Merrimack.

Within 2 miles, the terrain around Merrimack has only modest variations in elevation — a maximum elevation change of 289 ft around an average of 203 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,227 ft; within 50 miles, large variations in elevation — a maximum elevation change of 3,176 ft.

The land around Merrimack is covered by trees (73%) within 2 miles, trees (77%) within 10 miles, and trees (82%) within 50 miles.

2 miles
289 ft
10 miles
1,227 ft
50 miles
3,176 ft
treesgrasslandcroplandartificial surfaceswaterwetland
October weather nearby: Bedford 5.6 mi · Nashua 6.8 mi · Derry 8.7 mi · Manchester 9.3 mi · Derry Village 9.3 mi · Salem 16 mi · Dracut 17 mi · Methuen 18 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Merrimack (42.8651°, -71.4934°, elevation 154 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).