Weather in Boston in June

A good month. June works. It is not the peak, but nothing about it fights you. Highs average 23.9 °C, lows 13.9 °C, and rain falls on 13 days — nothing in the month is working against you.

June ranks 2 of 12 in Boston. Only September scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain on 13 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest June day reached 34.2 °C and the coldest night fell to 5 °C, and the wettest single day dropped 64 mm — roughly 57% of the month's rain in one day.

June is moderately variable: 46 mm in the driest year against 246 mm in the wettest, around an average of 113 mm. Roughly two Junes in three land near that average, and the third does something else entirely.

Wind is light at 1.4 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 79%, high enough to notice on the warm days without dominating them.

How June sits in the year

The month is on the way up: 4.8 °C warmer than May, and July adds another 4.1 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in June

June is at or near the longest days of Boston's year: 15.3 hours of daylight, holding steady all month. Evenings are the real gain — dinner outdoors still happens in full light.

Sea temperature

The sea sits at about 14.1 °C in June — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 19.7 °C in August and bottoms out at 4.6 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Peak season. Expect the highest prices of the year and to be booking well ahead.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

June in Boston versus nearby

If Boston is one option among several, the nearby comparison is worth making. New York City is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Bar Harbor is close enough to be a coin toss — 5.4 °C cooler, 1 day more rain.

So: June is effectively as good as it gets here — 6 points behind September, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Boston

See all twelve months in Boston, or where else to go in June.