New Hampshire has a humid continental climate, and honestly, the weather changes pretty dramatically from season to season. In winter, temperatures can plunge down to 10°F in January. But by July and August, summer highs climb into the 80s. New England’s location means the weather gets influenced by both Atlantic moisture and air masses sweeping in from the continent.
New Hampshire’s monthly weather shifts a lot—from frigid, snowy winters up north to warm, humid summers statewide. Temperatures range from 10-30°F in January to 58-82°F in July. The White Mountains and the northern parts usually get the brunt of the extreme stuff—more snow, colder temps—while things stay a bit more moderate down south. Precipitation? It stays pretty steady all year, about 3-4 inches a month.
Knowing these monthly weather swings helps people plan for New Hampshire’s ever-changing conditions. Each season’s got its own vibe, from winter sports when the snow piles up to hiking and leaf-peeping in the milder months. The state’s climate zones are all over the map, so you might see wildly different weather in different places, even in the same month.
Overview of New Hampshire’s Monthly Weather Patterns
New Hampshire’s humid continental climate brings four distinct seasons. Temperatures run anywhere from 10°F in the depths of winter to 82°F at the summer peak. The weather can flip fast—from icy, snowy winters to warm, sticky summers. Spring and fall are just the in-betweeners.
Climate Classification and Regional Characteristics
New Hampshire fits the humid continental climate type. There’s no real dry season, and summers get pretty warm. This setup gives the state four seasons with big temperature swings.
The average elevation sits at about 297 feet above sea level. Annual temps hover around 49°F, which is a bit cooler than the national average.
You’ll notice real differences between regions. Up north and in the White Mountains, it gets colder and snowier. Down south, things mellow out.
Coastal spots like Portsmouth catch a break thanks to the Atlantic. The ocean keeps winters a bit warmer and summers a bit cooler than what you’ll find inland.
Seasonal Weather Overview
Winter hits from December through February, bringing the coldest conditions of the year. Temperatures can drop to 10-35°F, and snow falls regularly, especially up north and in the mountains.
Spring creeps in from March to May. You’ll see temps climbing from 22-44°F in March up to 43-69°F by May. Snow melts, flowers pop up, and the landscape greens.
Summer runs June through August, bringing the heat. July is the hottest month, with temps peaking at 58-82°F. Southern New Hampshire often cracks the 80s, while it stays a bit cooler up north.
Fall starts in September and goes through November. September’s still mild at 48-71°F, but by November, it’s down to 28-47°F. Foliage goes wild, drawing people from all over.
Monthly Weather Transitions
Temperatures move in pretty predictable patterns. January is the coldest, averaging 10-30°F. July is the warmest, with averages from 58-82°F.
Precipitation holds steady all year, usually between 2.7 and 4.2 inches a month. November tends to be the rainiest at 4.2 inches, and February is the driest at 2.7 inches.
Snow rules the winter from December through March. As spring rolls in, rain starts to take over. Summer brings the occasional thunderstorm.
Fall changes fast. Temps drop from September’s 70s to November’s 40s. Up in the higher elevations, you might even see snow as early as October.
Monthly Temperature Trends in New Hampshire
New Hampshire really swings between extremes. Winters up north can dip below 0°F, while summers can hit the mid-80s. The coldest time is always January, and July always wins for heat.
Average Highs and Lows by Month
Winter is when things get brutally cold. January lows can hit -4°F to 15°F, especially up in the northern wilds. Southern spots see January highs from 32°F to 40°F. February is still cold, but it eases up just a bit.
Spring brings a steady warm-up from March to May. April averages lows of 28°F to 36°F and highs of 52°F to 60°F. By May, you’re looking at lows around 42°F to 49°F and highs from 65°F to 73°F.
Summer peaks in July. Average lows run 57°F to 63°F, and highs climb to 80°F to 87°F. August stays toasty, with lows of 55°F to 61°F and highs of 76°F to 84°F.
Fall starts cooling off in September, with lows from 47°F to 54°F. October drops to 37°F to 45°F at night, and highs hit 54°F to 62°F.
Record Temperatures and Extremes
Northern New Hampshire, especially the White Mountains, gets hammered with some of the coldest weather in the country. Mount Washington and its neighbors see wild winter lows.
The mountains do help shield southern areas from the worst arctic blasts. Still, winter can be rough everywhere.
It’s rare for northern New Hampshire to get above 90°F, even in summer. Down south, it gets hotter, but still not as extreme as some other states.
The north-south divide creates clear climate zones. Up north, it can feel almost subarctic. Down south, it’s more temperate.
Daytime vs. Nighttime Variations
Winter brings the biggest swings between day and night. Short days mean weak sunlight, so it stays cold nearly all the time.
Summer swings are gentler. Warm days mellow out into comfortable nights from June through August.
Spring and fall see the wildest daily temperature changes. Weather systems roll through, and you can go from chilly to warm in a single day.
Coastal areas in the southeast have less dramatic daily swings thanks to the ocean. Up in the mountains, those swings get even bigger, no matter the season.
Precipitation Patterns Throughout the Year
New Hampshire gets steady rainfall all year, with monthly averages from 78mm to 107mm. Even the so-called drier months still see plenty of moisture, which keeps the state green and lush.
Monthly Rainfall Averages
Rainfall barely changes month to month. You’ll usually see between 78mm and 107mm, no matter the season.
This regular pattern means you can pretty much count on rain at any time. The state racks up about 1,100-1,160mm of precipitation each year.
Major cities all follow this trend:
- Manchester: 1,114mm annually
- Nashua: 1,107mm annually
- Concord: 1,128mm annually
- Rochester: 1,160mm annually
- Dover: 1,142mm annually
Even in the driest months, there’s still a decent amount of rain. That steady water supply keeps forests dense and helps out the farms.
Wettest and Driest Months
New Hampshire doesn’t really have a dry season like other places. Even in months that seem dry elsewhere, rain keeps falling.
Winter brings both rain and snow, which adds up fast. Spring is all about rain showers as things warm up.
Summer storms keep the ground from drying out. Fall sticks with the steady rain as things cool off.
The difference between the wettest and driest months is pretty small. That’s probably why the fall colors are so amazing—trees never really dry out.
Humidity and Sunshine Hours
Humidity jumps around thanks to the climate. Summers get sticky because of the heat and all that rain.
In winter, humidity drops since cold air just can’t hold much moisture. Spring and fall land somewhere in the middle.
Sunshine hours change a lot between seasons. Summer brings the most sunny days, even with the rain.
Winter days are short and often cloudy. Spring and fall mix it up, with some sunny days and some gray ones—actually, it’s pretty good weather for getting outside.
The combo of steady rain and shifting sunshine really gives New Hampshire its unique weather.
Monthly Snowfall and Winter Weather in New Hampshire
Snowfall in New Hampshire is no joke, especially from November through March. The heaviest snow piles up in the northern mountains. Winter weather makes life a challenge, affecting travel, outdoor fun, and daily routines depending on where you live.
Typical Snowfall by Month
Snow season kicks off in November, with the first snowstorms usually arriving then. Accumulations stay pretty light at first.
December ramps things up, bringing more regular snow statewide. With temps dropping to 17°F to 40°F, snow sticks around.
January is the heart of winter. Up north, temps often fall below 0°F. Down south, lows range from -4°F to 15°F.
February keeps the snow coming. It’s another cold, snowy month, and snow cover stays deep almost everywhere.
March starts to turn things around, but don’t be fooled—big snowfalls can still show up. As the month goes on, things start to thaw.
Regions with the Heaviest Snowfall
The White Mountains in the north get absolutely buried. Mount Washington, Mount Madison, and Mount Adams see some of the most brutal winter weather in the country.
The North Country, covering the top third of the state, gets hit hard all winter. Deep snow is just part of life up there.
Mountain passes and trails collect huge amounts of snow. Without the right gear and experience, these spots can be downright dangerous in winter.
Down south, there’s less snow, but it’s still enough to mess with your plans pretty regularly.
Impact of Snowfall on Daily Life
Heavy snow makes mountain roads and trails risky all winter. If you’re traveling, you’ve got to be extra careful.
Winter sports fans love it though. New Hampshire’s snow is perfect for skiing and snowboarding.
Short winter days make it tough to get outside much. Sunlight is in short supply during the coldest months.
Road crews stay busy just keeping highways and local roads clear. It’s a constant battle.
Schools and businesses often have to adjust when big storms hit. Most places have backup plans for when winter weather throws a wrench in the works.
Weather Variations in Major New Hampshire Cities
Weather can look totally different depending on where you are in New Hampshire. Coastal spots stay milder, while inland cities ride out bigger temperature swings. Up in the mountains, the weather gets harsh—longer winters, cooler summers, and more extremes.
Manchester and Concord
Manchester gets the classic inland New Hampshire weather—hot summers, cold winters. Highs hit 83°F in July, but drop to just 33°F in January. Winter lows sink to 17°F, making it one of the colder big cities in the state.
Rainfall runs about 3.1 to 3.9 inches per month during the wettest times. Snowfall adds up fast, with nearly 14 inches in January and another 12.6 inches in February.
Concord sees much of the same, since it sits in the state’s interior too. Both cities miss out on the ocean’s moderating effects, so the temperature swings are bigger than in Portsmouth.
Clear skies show up about 46-62% of the time. Summer’s the best bet for good weather, and August usually brings the most clear days at 61%.
Portsmouth and Coastal Weather
Portsmouth gets milder weather, thanks to its spot right on the New Hampshire coast. The ocean keeps things more balanced, so summers don’t get too hot and winters aren’t as harsh as they are inland.
January highs usually hit 34°F, just a bit above Manchester’s 33°F. The contrast shows up more in summer—Portsmouth tops out at 80°F, while Manchester can reach 83°F.
Winter lows stick around 20°F, which is a few degrees warmer than what you get farther from the coast.
Rainfall in Portsmouth doesn’t quite match what you see inland. The city gets between 1.9 and 4.1 inches each month, with October bringing the most rain. Snowfall still adds up, but it’s less than what inland towns see—about 12.4 inches in January.
Wind speeds crank up along the coast, that’s for sure. Portsmouth averages 10.7 mph in January, compared to Manchester’s 6.2 mph. This breeze makes the temperature feel different throughout the year.
Northern Regions and the White Mountains
Berlin, up north in the mountains, brings some of New Hampshire’s wildest weather. Winter temperatures get brutal, with January lows dropping to just 5°F and highs barely making it to 25°F.
Snowfall piles up fast in this area. Berlin sees 14.8 inches in January and 15.3 inches in February. Even March brings 12.8 inches, so the snow sticks around well into spring.
Summers up here stay pretty cool. July only gets to 76°F, and nights can dip to 53°F. Honestly, it’s a great spot for summer if you want to skip the heat.
Precipitation acts differently in the mountains. Berlin gets more rainy days—July averages 12.9 days with some rain, while Manchester only gets 10.5. The mountains stir up their own weather, so rain comes more often but doesn’t always pour.
Seasonal Activities and Travel Tips by Month
New Hampshire shifts with the seasons, so what you can do really depends on the time of year. The weather shapes everything, from the best months for hiking to when you should pack an extra layer.
Best Months for Outdoor Adventures
May through October is the sweet spot for getting outside in New Hampshire. May brings comfortable temps, usually 17°C to 21°C, and you won’t run into big crowds on the trails.
June through August brings the heat, with temperatures between 25°C and 29°C. Perfect for:
- Hiking and camping in the White Mountains
- Swimming and boating on the lakes
- Rock climbing with good conditions
- Mountain biking when the trails are dry
September is just fantastic for outdoor lovers. It’s still warm, 19°C to 24°C, and you get those famous fall colors.
Early October keeps the hiking season going, with cooler temperatures from 12°C to 17°C. Most trails stay open before the snow shows up.
April can be tricky because mud season hits hard. Trails at higher elevations get messy and sometimes you just can’t get through.
Winter Sports and Snow Experiences
December through March turns New Hampshire into a winter playground. The White Mountains get plenty of snow, so skiing and snowboarding are top-notch.
January and February are the coldest, with temperatures between -4°C and 2°C. These months are best for:
- Skiing at the bigger resorts
- Cross-country skiing on groomed trails
- Snowshoeing in the state parks
- Ice climbing for the adventurous
December and March are a bit unpredictable. Early December might not have enough snow, and by March, warmer days can mess with the snow quality.
Winter activities take some planning because the cold can get intense. Weather in the mountains can flip fast, and temperatures drop way more up high.
If you’re after the best snow, you’ll want to head north or climb higher—those spots get the most reliable powder all season.
Seasonal Packing and Safety Advice
Winter months (December-March) really call for solid cold weather gear.
You’ll want a layered clothing system with moisture-wicking base layers.
Pack waterproof outer shells to keep snow off.
Don’t forget insulated boots that can handle sub-freezing temperatures.
Bring emergency supplies like extra food and heat sources—better safe than sorry.
Spring (April-May) can be tricky, so pack for a bit of everything.
Waterproof boots help a lot with muddy trails.
Rain gear is a must since spring showers show up often.
Stick with layered clothing to deal with all those temperature swings.
Summer (June-August) is easier, but you shouldn’t get complacent.
You’ll need sun protection—think hats and sunscreen.
Insect repellent keeps black flies and mosquitoes away.
A light rain jacket is smart for those surprise afternoon thunderstorms.
Fall (September-November) means the temps start dropping fast.
Pack warm layers as it can go from 24°C down to 6°C before you know it.
Waterproof gear is important since rain gets more frequent.
Toss in emergency supplies just in case an early storm rolls through.
Mountain safety always matters, no matter the season.
Weather can change in a flash at higher elevations.