Mild
Average highs are around 25°C, so days are mild rather than hot.
Weather Guide
Hyannis, Massachusetts, United States Average Monthly Weather
Weather score39Poor annual avg
Best months: July, August, June
Across the year, average daytime temperatures are around 14°C, sunshine averages 6.8h per day, and rainfall totals about 1123mm. Sea temperatures average 11°C across the year.
Annual weather
Annual averages
Temp
14°C
Rain
1123mm
Annual total
Sun
6.8h
Sea
11°C
Weather score
39
Poor avg
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 98mm, so some wet days are possible.
Bright
Sunshine averages 8.1h per day, so bright days are a strong part of the month.
Cool sea
Sea temperatures average 21°C, so the water can feel cool.
Map
Weather map
Compare Hyannis, Massachusetts, United States with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
August25°C average high
August is one of Hyannis' warmest months, with daytime heat above the yearly average.
Warmest monthsJune to September
This stretch sets the upper range for average daytime heat.
Rain
August98mm average rain
August sits near Hyannis' yearly rainfall average, so rain is a normal planning factor rather than an outlier.
Driest monthsFebruary, May to July, and September to October
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
August8.1 hours average sun
August is brighter than Hyannis' yearly average, though the strongest sunshine usually sits closer to the peak months.
Brightest monthsMay to August
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
August21°C average sea
August is one of Hyannis' warmest sea months, when swimming comfort is usually strongest.
Warmest seaJuly to September
Sea temperatures are usually near 20°C in this stretch, so swimming comfort is at its strongest.
Weather score
August65 weather score
August is one of Hyannis' best weather-score months, combining the strongest overall balance in the yearly averages.
Best weather monthsJuly to August
These months have the strongest weather score in the monthly averages.
