Your trips
Organize your trips easily with tabs
New York
Boston
Any date
+ Search
background

Boston in May: Weather, Average temperature and Climate

Take a look at past year’s weather for Boston in May and see if it is worth visiting.
Check flight prices to Boston on Avionero:
May

Weather in Boston in May 2025

Good Weather
Mild
🌧️
Rainy
🌊
Cold water
Are you considering a trip to Boston in May? Well, the weather is usually on your side with an average maximum temperature of +66°F and about 4 sunny days. Just keep in mind that there may be some rain, with an average of 16 rainy days and 99 mm of precipitation. Expect good weather and pack accordingly to enjoy the outdoors. Search flights in one click on Avionero.

Average weather

☀️
+66°F
Avg. max. temperature
+34°F
Min.
+95°F
Max.
99 mm
Total precipitation
67%
Avg. humidity
4 m/s
Avg. wind
4 ☀️
Sunny Days
10 ⛅️
Cloudy
16 🌦
Rainy
Our opinion: Boston has good weather in May.

Average temperature in Boston in May

Here are the expected maximum, average and minimum temperatures in Boston for May based on the historical data.
Last Year
Historical Data

The temperature in May is +72°F on average, with a range between a maximum of +86°F during the day and a minimum of +39°F at night.

The average maximum temperature goes up 38% by the end of the month, compared with the beginning of the month, from +63°F to +81°F.

Is Boston warm or cold in May?

Boston is typically mild in May.

Maximum temperatures go up compared to the previous month from +55°F to +66°F. The minimum temperature also goes up from +41°F to +50°F.

Pack a light jacket as it will be warm in the day and cool in the evenings.

Take a look at how May is compared to other months in Boston:

Water temperature in Boston in May

Water in Boston in May is Cold. It varies from +43°F to +52°F, with an average of +47°F. The air temperature averaging +66°F is higher than the water temperature.

In May, water temperatures are average relative to the rest of the year:

The warmest water temperatures in Boston are reached in August, when the average sea temperature rises to +67°F. The coldest water temperatures are in March, with an average of +38°F.

Can you swim in Boston in May?

We would not recommend swimming in Boston in May, the water is very cold (+47°F on average). Consider swimming only if you are an experienced cold-water swimmer with proper gear.
🦭
Cold
Below +61°F
🏄‍♂️
Fresh
61°F - 70°F
🏊
Comfortable
70°F - 77°F
👙
Warm
77°F - 82°F
🔥
Very warm
+82°C and up
You will need a full-body wetsuit, cap, gloves, a warm change of clothes, and a hot drink ready for after your swim.

Climate in Boston in May

Boston weather looks like this, on average, in May and the surrounding months.
AprilMayJune
Avg. temperature
+55°F+66°F+75°F
Min. temperature
+18°F+34°F+45°F
Max. temperature
+88°F+95°F+97°F
Rainfall
104 mm99 mm113 mm
Wind
4 m/s4 m/s3 m/s
Avg. water temperature
+42°F+47°F+57°F
Humidity
63%67%69%
Air pressure
1014 HPa1014 HPa1013 HPa
Sunny days
443
Cloudy days
101011
Rainy days
151614
Snowy days
100

May often has better weather than April. It’s getting warmer as May arrives. The average maximum temperature goes up from +55°F to +66°F during the day. As May arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 104 mm to 99 mm. Humidity rises from 63% to 67%. The average wind speed doesn’t change much during May, staying around 4 m/s. The amount of sunny days stay about the same, averaging 4 sunny days during the month.

June brings much the same weather, it remains good.

Wind

Wind speed in Boston in May based on historical data.
Last Year
Historical Data

The average wind speed is 4 m/s getting up to 8 m/s which is a medium breeze. You can feel it, especially getting out of the water.

The average wind speed in Boston is gradually decreasing during May, going from 8 m/s to 2 m/s over the course of the month.

Rain

Amount of rainfall in mm during May in Boston based on historical data.
Last Year
Historical Data
A chance of rain on a typical day in May stands at 35%, leading to total precipitation of around 106 mm. The maximum amount of rainfall per day is around 38 mm, which is moderate rain. May is a pretty wet month with over 11 rainy days, so don’t forget to pack an umbrella, raincoat, and a pair of wellies.
Here’s how May is compared with other months in the amount of precipitation, total mm:
Boston wettest month is July, where a typical day has a 45% chance of precipitation and 114 mm of rainfall per day. February, on the other hand, is the driest month with a mere 17% chance of precipitation and 54 mm of rainfall per day.

How was the weather last May in Boston?

This is the weather in Boston in May 2023:
1 May
🌫️
+63°F
2 May
🌧️
+60°F
3 May
☁️
+54°F
4 May
🌧️
+50°F
5 May
☁️
+57°F
6 May
☀️
+75°F
7 May
☀️
+78°F
8 May
🌧️
+75°F
9 May
☁️
+66°F
10 May
☀️
+73°F
11 May
☀️
+80°F
12 May
☁️
+84°F
13 May
☁️
+80°F
14 May
☀️
+73°F
15 May
☁️
+73°F
16 May
☁️
+80°F
17 May
☀️
+73°F
18 May
☀️
+65°F
19 May
☀️
+69°F
20 May
☁️
+66°F
21 May
☁️
+75°F
22 May
☀️
+67°F
23 May
☀️
+62°F
24 May
☀️
+75°F
25 May
☁️
+66°F
26 May
☀️
+65°F
27 May
☀️
+79°F
28 May
☀️
+87°F
29 May
☀️
+77°F
30 May
☀️
+66°F
31 May
☀️
+80°F
In May 2023 Boston had 17 sunny days, 10 cloudy days, and 3 rainy days. The average maximum temperature was +72°F, with an absolute maximum of +86°F and a minimum of +50°F. The average humidity was 63%, with a maximum of 100% and a minimum of 26%. The average wind speed was 4 m/s, with a maximum of 12 m/s and a minimum of 0 m/s.
Are you planning a trip in May?

Climate Change Over the Years

This is how Boston climate has changed over the last 43 years.

The climate in Boston in May has not changed that much over the last 43 years.

The average temperature was the lowest in 1992 (+57°F) and the highest in 2022 (+62°F). The driest year was 2016 with only 702 mm of rainfall, and the wettest year was 2021 with 2022 mm.

FAQ

Frequently asked questions about the weather in Boston in May:

Is May a good time to visit Boston?

May is a really good time to go to Boston. The weather is nice so plan your packing around outdoor activities and exploring. Check out other good time to visit Boston.

Can you sunbathe in Boston in May?

May has mild temperatures in Boston. Not ideal for sunbathing, but still good for daytime outdoor activities, but plan for cool evenings. Pack a light jacket and shorts!

Can you swim in Boston in May?

Swimming in Boston in May is challenging and not recommended for inexperienced swimmers or without proper equipment and preparation.

Is Boston rainy in May?

Boston is often rainy in May. You may get a bit damp when outside, so pack an umbrella, and maybe even a raincoat.

Is it sunny in Boston in May?

Usually, it’s not very sunny in Boston in May, often it’s pretty cloudy. Pack for any eventuality; layering can help reduce the number of bulky items needed.

Other cities in USA

Check out the weather for other cities in USA.

Monthly weather in Boston

Source of the data

For this page, we’ve looked at the typical weather in Boston, based on historical hourly weather data from January 1, 1979, to December 31, 2023.

For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.