Hyannis (Cape Cod) weather by month
The best time to visit Hyannis (Cape Cod) is June to August — 91/100 in July, 27°C and 7 rainy days. The best season is summer, June to August (87/100 on average).
The worst month is January at 35/100 — cold, rainy, clean air. See January →
Updated September 2026 · climate normals from ERA5 reanalysis
Planning the wider trip? Best time to visit United States →
Best season: June to August (87/100 on average) · worst January (35/100)
- Days
- 27°C
- Nights
- 19°C
- Wet days
- 7
- Sun
- 11.3 h
- Humidity
- 84%
- Daylight
- 15 h

Hyannis, month by month
Comfort score out of 100 for the kind of trip Hyannis is best for, the average high, rainy days and hours of sun a day from the climate normals, and how busy it tends to be.
What's on in Hyannis through the year
Festivals, natural spectacles, holidays and the seasons to watch out for — curated and sourced. The month pages carry the detail.
- May
- Figawi race weekend22–31 May (usually)Festival
- Memorial Day weekend23–25 MayHoliday
- Island ferry high season20 May – 15 Oct (usually)Opening
- June
- White shark season1 Jun – 31 Oct (usually)Nature
- July
- Independence Day3–5 JulHoliday
- Peak summer season1 Jul – 31 AugSeason
- August
- Labor Day weekend5–7 SepHoliday
- Hurricane season15 Aug – 31 Oct (usually)Hazard
- November
- Winter shutdown1 Nov – 15 AprSeason
Crowds in Hyannis in July
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsIsland ferry high season, Peak summer season, Summer break in United States(estimated)
Peak crowdsBusyShoulder seasonQuiet
Traveller notes on Hyannis
What people who have been say about the place — the year-round notes first, then month by month.
Cape Cod's own forum doesn't sugarcoat February: expect a real chance of high wind, biting cold and snow, and New England weather here is notoriously hard to predict from one day to the next. Multiple posters recommended layering with fleece under a windproof shell so you can still get outside comfortably. A good number of shops and restaurants that cater to the summer crowd simply close for the season, so plan meals ahead rather than expecting to wander and find something open. It's a legitimate visit for solitude and off-season prices, just not the postcard version of the Cape.
Forum posters describe August as typically the warmest month, often in the 80s-90sF and humid, though the Cape's ocean breezes keep it noticeably cooler than inland Massachusetts at the same time - a stretch of 90F+ days is possible, but so is a cooler, rawer spell within the same month. Posters call August rain genuinely unpredictable, ranging from a light sprinkle to a full washed-out day, though it's typically the lowest-rain month of the summer overall. Mosquitoes are a real, near-constant presence, especially in the evenings, with repellent treated as standard packing. Posters consistently name the last two weeks of August through September as the more reliably pleasant stretch compared to June or early August.
Add your own note from Hyannis's card on the map.