Cool
Average highs are around 18°C, so pack for cooler days.
May verdict
Portland, Maine, United States in May
Weather score34Poor
Poor for holiday weather
Average highs are around 18°C, so pack for cooler days. Sunshine averages 7.7h per day, enough for a balanced month. Rainfall averages 92mm, so some wet days are possible.
May weather
Monthly averages
Temp
18°C
Rain
92mm
Sun
7.7h
Sea
9°C
Weather score
34
Poor
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 92mm, so some wet days are possible.
Some sun
Sunshine averages 7.7h per day, enough for a balanced month.
Cool sea
Sea temperatures average 9°C, so the water can feel cool.
Map
Weather map
Compare Portland, Maine, United States with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
May18°C average high
May is close to Portland's yearly temperature average, giving a typical read on daytime heat.
Warmest monthsJune to September
This stretch sets the upper range for average daytime heat.
Rain
May92mm average rain
May sits on the drier side of Portland's year, which helps with sightseeing and transfers.
Driest monthsJanuary to October
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
May7.7 hours average sun
May is brighter than Portland's yearly average, though the strongest sunshine usually sits closer to the peak months.
Brightest monthsJune to August
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
May9°C average sea
May is close to Portland's yearly sea-temperature average, so swimming comfort is fairly typical.
Warmest seaJuly to September
Sea temperatures are usually near 17°C in this stretch, so swimming comfort is at its strongest.
Weather score
May34 weather score
May scores below Portland's yearly average, so the weather trade-offs are more noticeable.
Best weather monthsJuly to August
These months have the strongest weather score in the monthly averages.
Hotels in Portland, Maine, United States
Marriott
View all
The Ritz-Carlton, PortlandPortland, Oregon, USA
The Nines, a Luxury Collection Hotel, PortlandPortland, Oregon, USA
Portland Marriott Downtown WaterfrontPortland, Oregon, USA
The Bidwell Marriott PortlandPortland, Oregon, USA
The Westin Portland HarborviewPortland, Maine, USA
Sheraton Portland Airport HotelPortland, Oregon, USA