Connecticut has a humid continental climate, so you get four distinct seasons and some pretty dramatic weather swings as the year rolls along. Its spot in the northeastern U.S. means the weather can change a lot from month to month, which keeps things interesting for locals and visitors alike.
Connecticut’s monthly weather ranges from cold, snowy winters with temperatures often below freezing to warm, humid summers that can reach the upper 80s. Spring usually brings milder temps and plenty of rain, while autumn is downright comfortable and shows off with some amazing fall foliage. These seasonal shifts make outdoor plans and travel a bit of a puzzle, but also a treat if you time it right.
Knowing Connecticut’s monthly weather patterns helps people figure out what to wear, when to visit, or even if it’s worth planning that outdoor wedding. Weather can feel totally different along the coast compared to inland spots—Hartford, for example, doesn’t always match up with the shoreline. Whether you’re planning a trip or just living here, it helps to know what each month might throw your way.
Connecticut’s Climate Overview
Connecticut gets cold winters and warm, humid summers. Inland and coastal areas don’t always match up, but the differences aren’t huge. Coastal spots tend to be a bit milder all year.
Climate Classification and Characteristics
Connecticut falls into the humid continental climate category. That means you get real seasons, no question about it.
In winter, temps usually drop down to the low 20s°F at night and maybe reach the upper 30s°F during the day. Snow is a regular thing—Hartford gets about 10 inches in January and 9 inches in February.
When summer rolls in, it gets warm and sticky. Highs hit the low 80s°F and nights cool down to the mid-60s°F. July is usually the hottest.
Spring and fall feel pretty nice. You get those comfortable temps and a fair amount of rain. Connecticut averages 3-4 inches of precipitation every month, so bring an umbrella.
Humidity ramps up in the summer. July can get especially muggy, with about 13-14 days where it feels heavy and uncomfortable.
Regional Weather Variations
Inland and coastal Connecticut don’t always play by the same rules. Hartford shows what you can expect inland, while New Haven gives you the coastal vibe.
Temperature differences aren’t huge, but they’re there:
- Winter highs: Hartford 36°F, New Haven 37°F
- Summer highs: Hartford 84°F, New Haven 81°F
Coastal areas get slightly milder winters and cooler summers. Long Island Sound keeps the coast from going to extremes.
Wind patterns change depending on where you are. New Haven averages 8-9 mph winds all year. Hartford is a bit calmer at 4-7 mph, especially in summer.
Snowfall hits harder inland. Hartford gets more snow than New Haven, especially in the heart of winter. Coastal warming means New Haven sees about 3 inches less snow each year.
Monthly Weather Patterns in Connecticut
Connecticut’s seasons are pretty dramatic. Winters are cold and snowy, but by spring things start to thaw out. January is usually the coldest, with heaviest snowfall, and February is when winter slowly starts to let go.
January Weather and Snowfall
January is the coldest month in Connecticut. Average temps run from 20°F to 40°F, and the northern part of the state almost always gets hit harder than the coast.
Temperature Patterns:
- Average low: 20°F (-6°C)
- Average high: 40°F (4°C)
- Hartford usually sees lows around 18°F
Snow is the name of the game in January. Northern Connecticut often gets more than 10 inches in a month. The coast gets less, but still deals with regular storms.
Ice storms can cause real trouble. Roads, trees, and power lines get coated in ice, which makes travel dangerous and knocks out power.
January Weather Highlights:
- Lots of snowstorms
- Icy roads
- Clear, cold days between storms
- Short daylight hours
February Conditions and Transition to Spring
February doesn’t really let up, but you can start to see the tiniest hints of spring. It’s still cold, but not quite as brutal as January.
Temps edge up a bit as the month goes on. Early February feels a lot like January, but late February sometimes teases you with milder days. Hartford gets average highs near 42°F by the end of the month.
Snow keeps falling, though storms aren’t usually as intense or as frequent as in January. Sometimes, coastal towns get rain mixed in when it’s a little warmer.
Key February Features:
- Temperatures slowly rise
- Snow keeps coming
- Days get longer
- Weather can flip-flop a lot
The weather in February is unpredictable. You might get a blizzard one day and sunshine the next.
March Early Spring Shifts
March finally brings some real change. The snow starts to fade, but big storms can still surprise you.
March weather in Connecticut is a rollercoaster. You might wake up to frost but need a lighter jacket by afternoon. Hartford’s highs climb from the mid-40s to near 55°F.
March Weather Transitions:
- Snow and ice start melting
- Mud everywhere
- Rain becomes more common
- Precipitation can be all over the place
Rain takes over from snow as the main event. But nor’easters can still dump heavy, wet snow, especially up north.
Weather can swing wildly—one day feels like spring, the next like winter all over again.
April and May Mild Warming
April really feels like spring. Things warm up, flowers start blooming, and frost is less common, though a cold night can still sneak in.
April brings lows in the upper 30s and highs near 65°F. Hartford usually gets nice daytime weather—great for heading outside. Rain picks up, but snow is pretty rare now.
May is just about perfect. Afternoon temps climb into the 70s and humidity stays low.
Spring Weather Benefits:
- Great temperatures
- Moderate rain
- Not much humidity
- Lots of sun
Every now and then, late spring brings a strong thunderstorm. You might see heavy rain, gusty winds, or even a rare tornado, but that’s not the norm.
May sets the stage for summer. Warm days and cool nights make it a favorite for locals and visitors.
Summer Weather: June to August
Connecticut summers are warm and humid. Temperatures usually sit between the mid-60s and low 80s Fahrenheit. Thunderstorms and muggy air are pretty common during these months.
Temperature and Precipitation Trends
Summer temps in Connecticut usually range from 63°F to 83°F (17°C to 28°C). June kicks things off with highs in the upper 70s.
July is the hottest month. Highs often reach the low to mid-80s.
August stays warm, though sometimes it cools off a bit as the month wraps up. Inland spots like Hartford get the hottest.
Rainfall doesn’t change much in summer. Most of it comes from afternoon and evening thunderstorms.
Monthly Temperature Ranges:
- June: 60-78°F
- July: 65-83°F
- August: 63-83°F
Being near the coast helps keep temperatures from getting too extreme. Hartford and other inland cities tend to run a bit hotter than the shoreline.
Humidity and Sunlight Levels
Humidity is a big deal in Connecticut summers. It often makes things feel hotter than the thermometer says.
Morning humidity can hit 70-80%, then drop a bit during the day. Coastal areas stay stickier thanks to the ocean.
Summer days are long, especially in June. Sunlight sticks around for hours, and clear mornings are common. By afternoon, clouds usually start building up.
The sun is strong, so sunscreen is a must.
Heat and humidity together can make it feel pretty oppressive. Air conditioning is almost a requirement during the hottest weeks.
Dew points often climb above 60°F, which really adds to that sticky feeling. All that moisture helps fuel thunderstorms, too.
Heatwaves and Storms
Connecticut gets heatwaves when temps break 90°F for a few days in a row. This usually happens a couple times each summer.
Thunderstorms pop up regularly, especially in the afternoons. Heat, humidity, and unstable air make perfect storm fuel.
Common Storm Features:
- Heavy rain in short bursts
- Lightning and thunder
- Gusty winds up to 40 mph
- Occasional hail
Most storms hit between 2 PM and 8 PM. They can cool things off, at least for a little while.
Summer brings more severe weather warnings, so it’s smart to keep an eye on the forecast.
Flash flooding can be a problem in low-lying or poorly drained areas.
Tornadoes are rare, but strong storms can bring damaging winds. Hartford and nearby towns see more storm action than the coast.
Autumn and Early Winter: September to December
Connecticut shifts quickly from warm autumn days to cold winter weather between September and December. Temperatures drop from the 70s in September to freezing or below by December, and rain gives way to snow.
September and October Fall Foliage
September is when fall really gets going. Early September can still feel humid, with temps in the mid-70s to low 80s.
By mid-September, cooler air moves in. Highs fall to the 60s and 70s, and nights cool off into the 40s and 50s.
October is peak foliage time. Average temps run from 45°F to 65°F. The trees put on a show—reds, oranges, yellows everywhere.
Rain is the main type of precipitation. September averages about 3-4 inches, and October is about the same. All that rain keeps the trees happy.
The first frost usually shows up in late October up north. The coast holds out a little longer, sometimes until early November.
November Cooling Patterns
November feels like a sharp turn toward winter. Average temps drop to 35°F to 55°F.
Cold fronts from Canada start rolling in more often. They bring quick temperature drops and strong winds. Sometimes temps plunge 20-30 degrees in just a few hours.
Snow can show up for the first time in November, especially up north. Most of it melts fast, but late in the month you might see some stick around.
Daylight disappears quickly. By the end of November, the sun sets before 5 PM, which doesn’t help with the chill.
Coastal areas stay warmer than inland towns. Long Island Sound keeps shoreline temps 5-10 degrees higher than the interior.
December Onset of Winter
December means winter is here. Average temps range from 28°F to 45°F, and the north is always colder than the south.
Snowfall picks up and starts to stick. Connecticut usually gets 6-12 inches in December, with the northwest hills seeing the most.
Cold snaps can drop temps well below freezing. Nights often hit the teens or even single digits. Wind chill makes it feel even colder.
Daylight is in short supply—about 9 hours a day. The winter solstice around December 21st is the shortest day of the year.
Ice storms are a real threat in December. Freezing rain can coat everything in ice, causing power outages and making travel a mess.
City-Specific Monthly Weather: Focus on Hartford
Hartford gets all four seasons, with winter lows around 21°F and summer highs near 84°F. The city sees moderate precipitation all year, with most snow falling in February.
Hartford Monthly Temperature Ranges
Hartford’s temperatures follow the classic New England pattern. Winters are the coldest, with temps usually between 21°F and 35°F.
January and February are the toughest months. Temps rarely dip below 6°F but often stay below freezing for days.
Spring brings a slow warm-up. March starts in the 40s, and by late May, you can expect 60s and 70s.
Summer is warmest from June through August. Nights are in the mid-60s, and days reach the low-to-mid 80s. Rarely does it get above 92°F.
Fall cools off steadily. September starts out warm in the 70s, but by November, highs are in the 50s and lows start flirting with freezing.
Hartford Precipitation and Snowfall by Month
On average, Hartford gets about 23.29 millimeters of precipitation each month. The city usually sees rain on 38 days a year, so that’s only about 10% of the calendar.
February brings the most snowfall, with the heaviest accumulations. Snow usually falls for 5.7 days in February, piling up to around 1.14 inches.
December through March pack in the bulk of winter snow. January and March add their share, but February still outdoes them both.
Spring and fall mostly bring rain. These in-between seasons get moderate precipitation that keeps the region green.
Summers can’t seem to settle on a pattern for precipitation. Thunderstorms drop most of the rain during these months, so you’ll get sudden bursts instead of gentle showers.
Planning Your Visit According to the Weather
Connecticut’s four-season climate opens up different opportunities all year. If you know what to expect with the weather and plan your clothes and activities, your trip can be a lot smoother.
Best Months for Outdoor Activities
Spring (April-May) feels just right for hiking and checking out the state parks. Temperatures usually land between 50°F and 70°F, which is honestly perfect for being outside.
Summer (June-August) gives you the best shot at beach days, boating, and all the fun festivals. With temperatures from 70°F to 80°F, it’s easy to see why people flock outdoors.
Fall (September-October) is when Connecticut really shows off. The Litchfield Hills and Connecticut River Valley turn into a patchwork of color from mid-September through late October.
Hiking in autumn? The trails look incredible, and the air cools off to a comfy 50°F to 70°F.
Winter (December-February) cuts back on outdoor options, but some experiences only happen then. Snow sports pick up in the north, while the coast stays a bit milder.
Recommended Clothing by Season
Winter clothing in Connecticut means you have to come prepared. Temperatures dip to 20°F to 40°F, and the north gets even colder.
You’ll want insulated coats, warm boots, and lots of layers. Don’t forget gloves and hats if you’re spending time outside.
Spring attire should be all about layers. Mornings can be chilly, so a light jacket helps, but t-shirts work for the warmer afternoons.
Summer clothing is easy—stick with lightweight, breathable stuff. Shorts, t-shirts, and sandals fit most days, though you might want a light sweater for breezy evenings by the coast.
Fall wardrobe gets a bit more creative. Mix sweaters, light jackets, and comfy walking shoes to keep up with the changing temperatures during foliage season.
Weather Impacts on Local Events
Fall foliage season draws big crowds to Connecticut. Hotels and attractions fill up fast when the leaves hit their peak in September and October.
If you want to visit, you should lock in your accommodations early. Weekends get especially packed during foliage season.
Summer festivals and outdoor concerts really need good weather. Rain can shut down or delay events, so it’s smart to check the forecast before you make plans.
Winter weather shakes up indoor cultural events and holiday celebrations. Snow can make it harder to get to venues, but most events still go on.
Spring brings out garden tours and outdoor markets. Mild weather makes walking tours and outdoor dining way more appealing all over the state.