Climate and monthly weather forecastLondonderry, NH
Climate and monthly weather forecast
The climate of Londonderry
Based on the Köppen climate classification, Londonderry falls under the Dfb category, known as a Humid Continental climate with no dry season and warm summers. The town, located in New Hampshire, USA, is subject to varying weather conditions all throughout the year.Over the course of a year, temperatures fluctuate from a low of 18°F (-7.8°C) to a high of 81.7°F (27.6°C), while average humidity levels stay relatively steady, ranging between 72% and 81%. Londonderry experiences a fair amount of rainfall year-round, with measurements varying from 0.75" (19mm) to 1.38" (35mm) monthly. Snowfall, generally seen from November to April, peaks at 2.99" (76mm) in December.
January and February see the lowest UV index at 2, while the highest reaches 6 during the months of June, July, and August. Visibility generally holds steady at 5 to 6 miles throughout the year, while cloud coverage varies between 33% and 51%.
The best time to visit Londonderry
For those looking to take advantage of the warmer temperatures, June to August would be the most favorable time to visit Londonderry. During these months, the town experiences its highest average temperatures ranging from 74.5°F (23.6°C) to 81.7°F (27.6°C). Additionally, these months also boast the highest average sunlight hours, extending from 9 to 10.4 hours per day.The worst time to visit Londonderry
If avoiding colder weather and snow is a priority, it may be best to avoid visits during late autumn and winter months. November through March records the lowest temperatures, with lows dipping to as much as 18°F (-7.8°C). Snowfall is generally seen from November to April, amounting to as much as 2.99" (76mm) in December.Spring weather in Londonderry
In Londonderry, spring arrives with comfortable and rising temperatures. March sees a slight warmth entering the weather, with the mercury moving from a low of 26.4°F (-3.1°C) to a high of 41.2°F (5.1°C). As spring progresses, by May, temperatures average between 47.1°F (8.4°C) and 66.9°F (19.4°C). The quantity of rainfall in spring varies between 1.06" (27mm) and 0.98" (25mm), while April becomes the least humid with the level dropping to 72%.Summer weather in Londonderry
Summers in Londonderry are typically warm, with the average temperatures throughout June, July, and August varying from 54.5°F (12.5°C) to 81.7°F (27.6°C). The summer humidity levels stay fairly constant at around 75%, providing a comfortable level of warmth. Although summer experiences the highest rainfall levels, up to 1.3" (33mm) in July, it also offers the highest average daily sunlight hours, from 15.3 hours in June to 13.9 hours come August.Autumn weather in Londonderry
Autumn sees temperatures gradually decreasing, with an average high of 72.1°F (22.3°C) in September falling to 46.6°F (8.1°C) by November. The humidity levels rise modestly during this period, moving from 77% to 75%. Rainfall reaches its peak in October with 1.38" (35mm) experienced, with daylight hours reducing from 12.5 hours in September to 9.8 hours in November.Winter weather in Londonderry
The winter months in Londonderry, from December to February, bring about the coldest period of the year. Average temperatures dip to as low as 18°F (-7.8°C) and rise only up to 33.3°F (0.7°C) in February. Winter also marks the season with the most snowfall, reaching up to 2.99" (76mm) in December. Throughout the winter, average daylight hours decrease to a yearly low of 9.1 hours in December, while the UV index also drops to its lowest level of 2.Weather in January
January is distinguished by its chill, making it one of Londonderry's coldest months of the year. Even though this month strays far from the summer's heat, frequent snowfall does soften the winter days. This snowy atmosphere is accompanied by a relatively low daylight duration of 9.4 hours. Weather in January »Weather in February
Weather conditions in February remain relatively consistent with those of January. Despite the wintery low temperatures, February presents a slight enhancement in daylight hours to 10.6 hours. The wind chill persists and snowfall remains common. Weather in February »Weather in March
As Londonderry welcomes spring, March signifies a transitional period in the annual weather cycle. Departing from February's frigid conditions, the days grow in length and dormant landscapes begin to thaw. This is equally evident in the increase in temperature, notably to a scale from 26.4°F (-3.1°C) to 41.2°F (5.1°C), providing relief to the chill-weary residents. Weather in March »Weather in April
April’s weather is an embodiment of spring’s mildness in Londonderry. Temperatures continue to climb, and daylight persists for longer hours, uplifting the mood of the city. Rain showers persist and humidity remains moderate. The highlight of this month is the considerably increased temperature scale from 37.4°F (3°C) to 55°F (12.8°C). Weather in April »Weather in May
May manifests as an escalator towards summer, presenting longer daylight hours and more clear skies. The prevalent coolness of April gradually fades away, replaced by a subtle warmth. Sunshine becomes a frequent companion with minimal interruptions, aiding the flourishing flora. Weather in May »Weather in June
As the gateway to summer, June alters the weather narrative significantly. Clear skies dominate the month, the sun shines brightly, and rainfall typically takes a backseat. This jovial atmosphere substantiates the city's love for outdoors. Weather in June »Weather in July
July is undeniably Londonderry's sunniest and hottest month. It's the pinnacle of summer, characterized by bright, long days with virtually no snowfall. The city revels under the warm daylight, and evening storms are not uncommon. The temperature peaks for the year, fluctuating from 61°F (16.1°C) to a high of 81.7°F (27.6°C). Weather in July »Weather in August
August resonates with July's weather, portraying similar patterns with slight moderation. Clear skies abound, the sun maintains its dominant presence, and daylight maximizes the opportunities for outdoor activities. Rainfall remains at bay and temperatures are notably warm, with ranges from 59.9°F (15.5°C) to 80.1°F (26.7°C). Weather in August »Weather in September
September undoubtedly heralds the arrival of Autumn in Londonderry. It begins the descent from summer's height, and the color palette of the city undergoes transformation. Leaves change color, the heat subsides, and rainfall returns infrequently. Weather in September »Weather in October
In October, Autumn officially asserts its presence in Londonderry. The weather morphs continuously, with flurries making their first appearances towards the month's end. Gusty winds continue the narrative of transition, setting the stage for the upcoming wintry months. Weather in October »Weather in November
Londonderry in November feels the onset of winter. As autumn matures, the city gears up for the impending cold spell. Sunshine becomes less intense and snowfall returns to the fore. November is characterized by reduced daylight hours and temperatures between 33.6ºF and 46.6ºF. Weather in November »Weather in December
December ushers in Londonderry's winter, transforming the cityscape into a snowy wonderland. The cold clings tightly, and daylight becomes a precious commodity. Rainfall sees a marginal rise, but snowfall typically steals the spotlight. Weather in December »Updated: Feb 13, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
The coldest period in Londonderry tends to be January, when average temperatures fluctuate between a high of 30.6°F (-0.8°C) and a low of 18°F (-7.8°C).
January is the month with the least rainfall in Londonderry, New Hampshire. Rain falls for 4.1 days and accumulates 0.75" (19mm) of precipitation.
Throughout the year, in Londonderry, New Hampshire, there are 104.4 rainfall days, and 12.95" (329mm) of precipitation is accumulated.
Months with snowfall in Londonderry, New Hampshire, are January through May, October through December.
Throughout the year, in Londonderry, New Hampshire, there are 26.1 snowfall days, and 11.54" (293mm) of snow is accumulated.
The months with the lowest UV index in Londonderry, New Hampshire, are January through March, November and December, with an average maximum UV index of 2.
The most humid month is February, with an average relative humidity of 81%.
With an average of 4.6h of sunshine, February has the least sunshine of the year.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Londonderry, and the time zone changes from EST to EDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from EDT to EST.
The least humid month in Londonderry is April, with an average relative humidity of 72%.
In Londonderry, New Hampshire, snow does not fall in June through September.
June has the longest days of the year, with an average of 15h and 18min of daylight.
The months with the highest UV index in Londonderry are June through August, with an average maximum UV index of 6.
The warmest period in Londonderry is July, when temperatures fluctuate between an average high of 81.7°F (27.6°C) and a low of 61°F (16.1°C).
August has the most sunshine of the year, with an average of 10.4h of sunshine.
The month with the most rainfall in Londonderry is October, when the rain falls for 9.4 days and typically aggregates up to 1.38" (35mm) of precipitation.
The month with the most snowfall is December, when snow falls for 4 days and typically aggregates up to 2.99" (76mm) of snow.
December has the shortest days of the year in Londonderry, with an average of 9h and 6min of daylight.
Average temperature
Londonderry, NH
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (30.6°F).
The month with the highest average low temperature is July (61°F).
The coldest month (with the lowest average low temperature) is January (18°F).
Average pressure
Londonderry, NH
- Average pressure in January:
30.01"Hg - Average pressure in February:
29.99"Hg - Average pressure in March:
30.03"Hg - Average pressure in April:
29.96"Hg - Average pressure in May:
30"Hg - Average pressure in June:
29.92"Hg
- Average pressure in July:
29.94"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.05"Hg - Average pressure in October:
30.01"Hg - Average pressure in November:
30.07"Hg - Average pressure in December:
30.03"Hg
The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Londonderry, NH
- Average wind speed in January:
8.3mph - Average wind speed in February:
8.1mph - Average wind speed in March:
7.9mph - Average wind speed in April:
7.6mph - Average wind speed in May:
6.3mph - Average wind speed in June:
5.7mph
- Average wind speed in July:
5.2mph - Average wind speed in August:
5.1mph - Average wind speed in September:
5.5mph - Average wind speed in October:
6.7mph - Average wind speed in November:
7.1mph - Average wind speed in December:
7.8mph
The windiest month (with the highest average wind speed) is January (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity
Londonderry, NH
The month with the highest relative humidity is February (81%).
The month with the lowest relative humidity is April (72%).
Average rainfall
Londonderry, NH
- Average rainfall in January:
0.75" - Average rainfall in February:
0.83" - Average rainfall in March:
1.18" - Average rainfall in April:
1.06" - Average rainfall in May:
0.98" - Average rainfall in June:
1.18"
The wettest month (with the highest rainfall) is October (1.38").
The driest month (with the least rainfall) is January (0.75").
Average rainfall days
Londonderry, NH
- Average rainfall days in January:
4.1 days - Average rainfall days in February:
4.5 days - Average rainfall days in March:
8.3 days - Average rainfall days in April:
9.8 days - Average rainfall days in May:
12 days - Average rainfall days in June:
12.1 days
- Average rainfall days in July:
11.9 days - Average rainfall days in August:
10.4 days - Average rainfall days in September:
8.4 days - Average rainfall days in October:
9.4 days - Average rainfall days in November:
7.2 days - Average rainfall days in December:
6.3 days
The month with the highest number of rainy days is June (12.1 days).
The month with the least rainy days is January (4.1 days).
Average snowfall
Londonderry, NH
- Average snowfall in January:
2.4" - Average snowfall in February:
2.32" - Average snowfall in March:
1.85" - Average snowfall in April:
0.91" - Average snowfall in May:
0.04" - Average snowfall in June:
0"
The month with the highest snowfall is December (2.99").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Londonderry, NH
- Average snowfall days in January:
7.1 days - Average snowfall days in February:
5.9 days - Average snowfall days in March:
5.7 days - Average snowfall days in April:
1.1 days - Average snowfall days in May:
0.1 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.5 days - Average snowfall days in November:
1.7 days - Average snowfall days in December:
4 days
The month with the highest number of snowfall days is January (7.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Londonderry, NH
- Average daylight in January:
9h and 30min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 42min - Average daylight in June:
15h and 18min
- Average daylight in July:
15h and 0min - Average daylight in August:
13h and 54min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 6min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in January:
5h and 6min - Average sunshine in February:
4h and 36min - Average sunshine in March:
5h and 42min - Average sunshine in April:
8h and 6min - Average sunshine in May:
8h and 24min - Average sunshine in June:
9h and 0min
- Average sunshine in July:
10h and 6min - Average sunshine in August:
10h and 24min - Average sunshine in September:
8h and 24min - Average sunshine in October:
5h and 54min - Average sunshine in November:
5h and 30min - Average sunshine in December:
4h and 48min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days
Londonderry, NH
- Average sunshine days in January:
21.3 days - Average sunshine days in February:
18.9 days - Average sunshine days in March:
18.6 days - Average sunshine days in April:
18.3 days - Average sunshine days in May:
17.1 days - Average sunshine days in June:
16.7 days
- Average sunshine days in July:
17.1 days - Average sunshine days in August:
18 days - Average sunshine days in September:
20 days - Average sunshine days in October:
20 days - Average sunshine days in November:
21 days - Average sunshine days in December:
21.3 days
The months with the most sunshine days are January and December (21.3 days).
The month with the least sunshine days is June (16.7 days).
Average UV index
Londonderry, NH
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover
Londonderry, NH
The month with the most cloud cover is March (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility
Londonderry, NH
The months with the highest visibility are January, April, November and December (6mi).
The months with the lowest visibility are February, March, May, June, July, August, September and October (5mi).
