Climate and monthly weather forecast
Sullivan, NH

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Weather in January

January, the same as December, in Sullivan, New Hampshire, is another subzero cold winter month, with an average temperature ranging between max 27.9°F (-2.3°C) and min 15.1°F (-9.4°C). With average high and low temperatures of 27.9°F (-2.3°C) and 15.1°F (-9.4°C) respectively, January is Sullivan's coldest month. Weather in January »

Weather in February

The last month of the winter, February, is another freezing cold month in Sullivan, New Hampshire, with an average temperature ranging between min 16.5°F (-8.6°C) and max 31.1°F (-0.5°C). February's arrival registers an average high-temperature of a still subzero cold 31.1°F (-0.5°C), closely aligning with the temperature of the previous month. Weather in February »

Weather in March

The first month of the spring, March, is an icy month in Sullivan, New Hampshire, with an average temperature ranging between min 24.3°F (-4.3°C) and max 39.4°F (4.1°C). The beginning of March marks a minor shift in the average high-temperature, moving from February's freezing cold 31.1°F (-0.5°C) to a wintry 39.4°F (4.1°C). Weather in March »

Weather in April

April is a fresh spring month in Sullivan, New Hampshire, with temperature in the range of an average low of 35.1°F (1.7°C) and an average high of 52.9°F (11.6°C). With the beginning of April, Sullivan's average high-temperature sees an increase, transitioning from a wintry 39.4°F (4.1°C) in March to a fresh 52.9°F (11.6°C). Weather in April »

Weather in May

The last month of the spring, May, is a refreshing month in Sullivan, New Hampshire, with an average temperature ranging between max 66°F (18.9°C) and min 45.3°F (7.4°C). The average high-temperature increases in May, moving from a cool 52.9°F (11.6°C) in April to a comfortable 66°F (18.9°C). Weather in May »

Weather in June

The first month of the summer, June, is an agreeable month in Sullivan, New Hampshire, with an average temperature fluctuating between 52.5°F (11.4°C) and 73.2°F (22.9°C). Entering June, Sullivan notices a subtle temperature elevation, with the average high-temperature advancing from May's enjoyable 66°F (18.9°C) to a pleasant 73.2°F (22.9°C). Weather in June »

Weather in July

July in Sullivan, New Hampshire, is a moderately hot summer month, with an average temperature ranging between min 58.6°F (14.8°C) and max 79.9°F (26.6°C). July, with average temperatures reaching a high of 79.9°F (26.6°C) and a low of 58.6°F (14.8°C), is the warmest month. Weather in July »

Weather in August

August, the last month of the summer in Sullivan, is also a moderately hot month, with an average temperature varying between 78.1°F (25.6°C) and 56.8°F (13.8°C). The advent of August sees the average high-temperature at a still warm 78.1°F (25.6°C), subtly shifted from July's 79.9°F (26.6°C). Weather in August »

Weather in September

September, the first month of the autumn in Sullivan, is still a pleasant month, with an average temperature fluctuating between 70°F (21.1°C) and 50.9°F (10.5°C). As August shifts into September, a minor alteration in temperatures is observed, with average highs reducing from a warm 78.1°F (25.6°C) to a pleasant 70°F (21.1°C). Weather in September »

Weather in October

October, like September, is a moderate autumn month in Sullivan, New Hampshire, with temperature in the range of an average low of 42.1°F (5.6°C) and an average high of 56.8°F (13.8°C). October comes with a drop in the average high-temperature, falling from September's pleasant 70°F (21.1°C) to a mild 56.8°F (13.8°C). Weather in October »

Weather in November

November, the last month of the autumn in Sullivan, is another chilly month, with an average temperature ranging between max 44.4°F (6.9°C) and min 31.3°F (-0.4°C). The average high-temperature drops in November, from October's refreshing 56.8°F (13.8°C) to a chilly 44.4°F (6.9°C). Weather in November »

Weather in December

The first month of the winter, December, is also an icy month in Sullivan, New Hampshire, with an average temperature varying between 33.4°F (0.8°C) and 22.8°F (-5.1°C). The onset of December introduces a moderate change in Sullivan's weather, with average high-temperatures falling from November's chilly 44.4°F (6.9°C) to a cold 33.4°F (0.8°C). Weather in December »

Frequently asked questions

What time of the year is the coldest?

In Sullivan, January is the coldest month, with temperatures averaging a high of 27.9°F (-2.3°C) and a low of 15.1°F (-9.4°C).

How much does it rain?

Throughout the year, there are 125.1 rainfall days, and 11.69" (297mm) of precipitation is accumulated.

When does it snow?

Months with snowfall are January through May, October through December.

When does it snow the most?

The month with the most snowfall is January, when snow falls for 9.2 days and typically aggregates up to 2.64" (67mm) of snow.

How many days does it snow in Sullivan?

In Sullivan, during the entire year, snow falls for 39.8 days and aggregates up to 10.2" (259mm) of snow.

What are the months with the lowest UV index?

The months with the lowest UV index are January through March, October through December, with an average maximum UV index of 2.

What is the most humid month?

February is the most humid month, with an average relative humidity of 85%.

What is the month with the least sunshine?

February has the least sunshine of the year, with an average of 4.4h of sunshine.

What is the driest month?

The month with the least rainfall is March, when the rain falls for 10 days and typically collects 0.75" (19mm) of precipitation.

When is Daylight Saving Time (DST)?

On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, 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.

What is the least humid month?

April is the least humid month, with an average relative humidity of 74%.

When it does not snow?

In Sullivan, snow does not fall in June through September.

When are the longest days?

With an average of 15h and 18min of daylight, June has the longest days of the year.

What part of the year is the hottest?

In Sullivan, temperatures reach their average annual highs in July, measuring 79.9°F (26.6°C) and a minimum average of 58.6°F (14.8°C).

What is the rainiest month?

The month with the most rainfall is July, when the rain falls for 13.3 days and typically aggregates up to 1.3" (33mm) of precipitation.

What is the month with the highest UV index?

With an average maximum UV index of 6, July is the month with the highest UV index.

What month has the most sunshine?

With an average of 10.3h of sunshine, August has the most sunshine of the year.

What is the month with the shortest days?

December has the shortest days of the year, with an average of 9h and 6min of daylight.

Average temperature
Sullivan, NH

Average temperature - Sullivan, NH

The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (27.9°F).

The month with the highest average low temperature is July (58.6°F).
The coldest month (with the lowest average low temperature) is January (15.1°F).

Average pressure
Sullivan, NH

Average pressure - Sullivan, NH

The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed
Sullivan, NH

Average wind speed - Sullivan, NH

The windiest months (with the highest average wind speed) are January, February and March (7.9mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).

Average humidity
Sullivan, NH

Average humidity - Sullivan, NH

The month with the highest relative humidity is February (85%).
The month with the lowest relative humidity is April (74%).

Average rainfall
Sullivan, NH

Average rainfall - Sullivan, NH

The wettest month (with the highest rainfall) is July (1.3").
The driest month (with the least rainfall) is March (0.75").

Average rainfall days
Sullivan, NH

Average rainfall days - Sullivan, NH

The month with the highest number of rainy days is May (14.6 days).
The month with the least rainy days is January (6.3 days).

Average snowfall
Sullivan, NH

Average snowfall - Sullivan, NH

The month with the highest snowfall is January (2.64").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days
Sullivan, NH

Average snowfall days - Sullivan, NH

The month with the highest number of snowfall days is February (9.4 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight / Average sunshine
Sullivan, NH

Average daylight / Average sunshine - Sullivan, NH

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).

The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).

Average sunshine days
Sullivan, NH

Average sunshine days - Sullivan, NH

The month with the most sunshine days is November (20.2 days).
The month with the least sunshine days is May (13.8 days).

Average UV index
Sullivan, NH

Average UV index - Sullivan, NH

The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).

Average visibility
Sullivan, NH

Average visibility - Sullivan, NH

The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).

Sullivan, New Hampshire, USA

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