The National Park is located in the east of Maine. Due to its northern position, temperatures are somewhat low the whole year round, when you compare them to warmer US and European locations.
In general, the weather at Acadia National Park can be best described as unpredictable. While summers are typically sunny and warm, the weather can shift without warning. A day that begins with clear skies in Bar Harbor could culminate in rain, fog, or, unusual situations.
The weather fluctuations in Maine, along with the entirety of New England, are more erratic and severe compared to nearly all other regions in the United States.
In winter, the park turns into a winter wonderland, with snowfall and temperatures below freezing. Snowstorms aren’t uncommon either, due to strong low-pressure cores that often move over the area. In the summer, temperatures are pleasant to perform outdoor activities such as hiking or kayaking.
Furthermore, the precipitation amounts are the lowest in late summer, due to the decreased low-pressure activity, which rules the weather in the latter half of the fall, winter, and early spring. The weather can be uncertain during the whole year, but especially in June when summer thunderstorms are common.
Everything mentioned in this article is based on climatic data, keep in mind that the weather can change day to day.
Spring Weather
With the winter being the coldest season and the summer the warmest, spring is the transition between both in Acadia National Park. This boasts a lot of variety, early March is still somewhat wintery, with some roads and facilities still being closed due to winter weather.
Late spring can already hint a bit at summer. Due to the northern location of the National Park, temperatures are lower all year-round compared to other areas in the United States and Europe. Spring isn’t an exception, temperature-wise it can feel chilly to people used to warmer regions, especially in March and early April.
The average temperatures are on the rise during the whole season. This rise is pretty linear when we look at the averages, in reality, there will be ups and downs in temperature during the spring.
March: The coldest month of the spring is logically March, especially the first half of the month can still be wintery with temperatures barely above freezing and snow.
A local about March: Weather in Acadia in March can be a real guessing game. From temps in the high 40s to very cold days with snowstorms that dump several inches of snow over a couple of days.
Road Closures: Besides the closed Park Loop Road (which usually reopens mid-April), the historic carriage roads might be closed from March until late April.
From then on temperatures start to rise quickly, in mid-April the average maximum temperatures touch 50°F (10°C). However, keep in mind that April in Acadia National Park is known as the mud season: Due to melting snow and ice, the trails are getting muddy. If you are looking to hike, consider late April or check the granite ledges in Acadia, which are great for hiking in April.
Good to know: In March and April most of the seasonal shoreside seafood shacks, hiking trails, and water-related activities are still closed. There is a good chance lakes and ponds will still be ice-covered.
May: At the end of May, temperatures reach 65°F (18°C). In general, May is the best spring month in terms of weather as it is mostly pleasant and warmer during the day. The evenings and early mornings are still a bit chilly though.
Good to know: Depending on the spring weather and temperatures, usually around mid-may the trees begin to leave out in Acadia National Park.
Average maximum temperatures:
- March: 39°F (4°C)
- April: 50°F (10°C)
- May: 61°F (16°C)
Wind and Perceived Temperature
While wind is the strongest in winter, wind speeds are still moderate and occasionally strong in March. This has quite some influence on the perceived temperatures. The perceived temperatures generally reach about 34°F (1°C) during the day and fall to 16°F (-9°C) during the night and morning in mid-March.
The feel-like temperatures start to rise rapidly in April and May due to calmer winds and higher temperatures. Perceived temperatures are close to the actual maximum temperatures in April and May. During the night, they do still drop to under 32°F (0°C) in mid-April and are about 40°F (4°C) in mid-May.
Wind directions: A south wind in spring is usually colder than a north wind along the coast at Bar Harbor. The wind direction plays a big factor. If you happen to come during a period of northerly or westerly winds, it will be pleasant weather in late spring: dry, sunny, and warm.
For most people, especially March and April will still be too unpleasant. But the resulting benefit is that the crowds haven’t arrived yet in that period of the year.
Precipitation | Rain – Snow
When we take a look at the precipitation, we see a slow upward trend during the spring. March is generally the driest month of the three, with about one in four days receiving some amount of precipitation.
At the end of May, about 32% of all days receive precipitation. In April and May, most of the precipitation is rain.
Good to know: While May is the most pleasant of all spring months, there is a good chance of rain. Be prepared and pack rain gear.
In March, snow is still a possibility. Keep in mind that March weather can be very unpredictable, snowstorms have happened in March and will continue to be a possibility. On the other hand, the temperatures can also touch 50°F (10°C) on some occasions, especially towards the end of March.
On average, snowfall is about 5 inches (13cm) cumulatively during March.
The average chance of sun is remarkably stable during the spring, about 45% of days are at least partially sunny. These percentages are higher in summer, but compared to other places in the US, especially the south, sunshine is pretty uncommon. Compared to Western and Northern Europe though, Acadia National Park is a pretty sunny place.
Summer Weather
In Acadia National Park June, July, and August are the three warmest months of the year. The absolute highest temperatures are normally reached in late July. The summer boasts very pleasant temperatures to enjoy outdoor activities during the day.
However, the weather is unpredictable in Acadia, especially in June. The other two summer months are most of the time more stable. Ocean water temperatures remain too low to swim during the whole year, but reach their peak in August at about 57°F(14°C).
June is the coolest month of the summer months. In June, temperatures are still rising slowly, approaching the maximum in late July. In mid-June temperatures are around 70°F (21°C) at the warmest moment of the day, which most of the time is in the afternoon, at around 3 PM or 4 PM.
The minima, which are reached in the early morning at around sunrise, are consistently about 18°F (10°C) lower than the maximum.
During the first half of July temperatures are rising slowly, starting at 73°F (23°C) at the start of the month and reaching 75°F (24°C) in the latter half.
In August temperatures are slightly falling again, but still between 72-75°C (22-24°C). Keep in mind that the temperatures can vary from day to day.
Average maximum temperatures:
- June: 70°F (21°C)
- July: 75°C (24°C)
- August: 73°F (23°C)
Wind and Perceived Temperature
Due to the location near the ocean, it can get quite windy in Acadia National Park during the fall and winter. But in summer, due to changes in pressure patterns, wind speeds are significantly lower. The major wind directions are south and west, this means that wind is most often coming from over land, which leads to the wind feeling less cold.
Overall perceived temperatures don’t differ a lot from the actual temperatures in summer. Another factor to take into consideration to determine the feel-like conditions is the humidity.
About one-third to half of the days can feel quite humid, due to higher humidities combined with higher temperatures. This is especially the case around late July, early August. On these humid days, you will sweat more easily, but it won’t get to the point that it will feel oppressive.
Precipitation | Rain
June is generally the most cloudy month of the summer. About half of all days in June are at least somewhat sunny. The weather in June is the most unpredictable, it rains on about one-third of the days.
However, this rain is most of the time in the form of showers that won’t last long but also can initiate seemingly out of nowhere. These showers can be accompanied by some thunder, but it’s nothing compared to the thunderstorms in other areas, like the central USA.
July and August are generally more stable months with more sun (on about 60% of days) and less rain. August is the driest month of the year, with only on average 6 days with rainfall. These factors combined with summer holidays make July and August the busiest months in Acadia National Park.
Fall Weather
The peak in temperatures in Acadia NP is now behind us. Temperatures are falling during the whole season. That’s one of the reasons that every month is wildly different during the fall.
September still has some summer vibes, while November can get quite wintery already. Temperatures decrease rapidly from 70°F (21°C) in early September to a meager 41°F (5°C) at the end of the season in late November.
During the fall season, winds are picking up speed, precipitation is getting more common and sunny days need to make place for cloudy ones.
In early September, daily maximum temperatures can still reach 70°F (21°C), which is pleasant for outdoor activities like hiking. In the latter half of September, temperatures are already lower, around 64°F (18°C).
Minimum temperatures, which are reached at sunrise are 50°F (10°C), these drop to 41°F (5°C) in mid-November and regularly go below freezing in the second half of November.
Maximum temperatures remain falling during October. Mid-October temperatures won’t go higher than 56°F (13°C). In mid-November, this value is reduced further to 46°F (8°C).
Average maximum temperatures:
- September: 68°F (20°C)
- October: 56°F (13°C)
- November: 46°F (8°C)
Wind and Perceived Temperature
The wind direction turns more and more to the northwest during the fall. With that, outbreaks of colder air can take place and cause some early winter weather in November. Wind speeds are on the rise.
In September winds are generally quite calm, on the same level as the summer months. Although it’s really uncommon, hurricanes can hit Maine. September is the most active hurricane month because seawater temperatures are the highest. In the case of a hurricane, wind speeds can reach up to 74mph (120km/h).
However, such hurricanes are rare and they only occur about once every 10-20 years. Average wind speeds are on the rise, and especially in November, they have an effect on the perceived temperature.
Perceived temperatures fall below 41°F (5°C) in November during the day, and below 25°F (-4°C) in the early morning. Make sure to bring suitable clothes.
Precipitation and Clouds
In September at least 60% of the days are somewhat sunny, but it depends on pressure patterns. This percentage drops to 55% in mid-October and 50% in mid-November.
Every year in late September, early October the tree’s leaves turn into those beautiful colors. If the sun comes out, this creates beautiful vistas.
Precipitation-wise, September is the best fall month to visit Acadia National Park, it even is the second driest month in the whole year.
Only one out of every four days receives rain. Daily chances of precipitation rise steadily to 32% in mid-November. Especially in the latter half of November precipitation can fall as snow or a rain-snow mixed form. On average there falls about 6 inches (15cm) of snow during the November month.
7 Fall Color Tips
- Start: The leaves in Acadia National Park usually start turning in late September. Check foliage conditions here: Maine’s Official Fall Foliage Website
- Peak Time: The foliage peak in Acadia National Park is in mid-October. The best weeks are the first until the third week in October.
- Crowds: During autumn it’s very busy in the park from the end of September until mid-October (Columbus Day weekend).
- Hotels & Facilities: Prices are often at their highest until mid-October. Book well in advance. They drop a little after Columbus Day. Most lodging establishments remain open during October as well as most restaurants and shops. However, a few close after Columbus Day weekend. Booking tips: Hotels Acadia
- Weather: The weather is often pleasant throughout October. Crisp and brilliant days. Gorgeous orange red and yellow leaves against a crisp blue October sky. Temperatures range between 40-60°F (7-15°C).
- Sweet Spot Week: Without the heavy crowds and lower rates, the week after Columbus Day is still great to watch the fall colors.
- End: The last week of October is usually still good, but sometimes the best leaves already have fallen then. The first week of November is definitely too late, leaf peeping season is already over.
Winter Weather
As everywhere in the northern hemisphere the months of December, January, and February are the coldest. Due to its location up north in the USA, it can get especially cold in Acadia National Park, in comparison with other areas on the East Coast, like New York City.
For some people, the weather will be too cold to stay outdoors for more than just half an hour, but the winter brings majestic landscapes with it, which gives the National Park a whole other feel.
December: Temperature-wise, December is generally the least cold month, with temperatures a little above freezing during (35°F, 2°C) the day, and a little under 32°F (0°C) in the nights and mornings.
January: These temperatures descend into January and reach their minimum in mid-January, with average high temperatures of 30°F (-1°C) during the day. You will find even lower temperatures when you ascend into the mountains.
February: In February, the temperatures start to gently rise again to 32°F (0°C) and even slightly higher towards the end of the month. February is still a typical winter month in terms of weather.
Keep in mind that based on the location of pressure zones, temperatures can widely vary from the means.
Average maximum temperatures:
- December: 35°F (2°C)
- January: 30°F (-1°C)
- February: 32°F (0°C)
Good to know: Some roads like the Park Loop Road and facilities are closed in the winter in Acadia National Park, make sure to check beforehand which roads and facilities are open. Check the official website: NPS – Acadia National Park: Visiting in Winter
Wind and Perceived Temperature
The wind picks up in the winter months, the winter and fall are the windiest seasons in Acadia National Park. Due to the moderate and sometimes even strong winds, the perceived temperatures are lower than the actual temperatures, especially in open places, like Cadillac Mountain or anywhere along the coast.
The average perceived temperature goes as low as 23°F (-5°C) during the day in the coldest part of the winter in Acadia National Park. In the morning, they can even drop to 5°F (-15°C). Make sure you wear warm enough clothes when you’re going outdoors in such temperatures.
Precipitation | Rain – Snow
Average precipitation amounts do not vary a lot during the year. Of the winter months, December is the wettest. About one-third of all days receive some type of precipitation. About half of the precipitation falls as rain, the other half as snow or mixed snow.
In January and February, more than half of the precipitation comes down as snow. The chance of precipitation goes down in these months, with an average daily precipitation probability of 25%. The National Park receives about 50 inches (127cm) of snow during the winter.
When it rains/snows it often rains/snows a lot, snowstorms are a possibility in Acadia National Park during the winter. Besides precipitation, the sun is also an important factor in creating the experience. The winter is one of the more cloudy seasons, about half of the days receive some sun, others receive next to none.