Portland
Maine, USA
Long-term weather forecast
Long-term weather forecast

August weather forecast and climate
Portland, ME

Dusk view of the lit skyscrapers of the Portland city in Maine
Dusk view of the lit skyscrapers of the Portland city in Maine
August, the last month of the summer, in Portland, is another warm month, with average temperature fluctuating between 58.3°F (14.6°C) and 77.7°F (25.4°C).

Temperature

In August, the average high-temperature is relatively the same as in July - a still warm 77.7°F (25.4°C). In August, the average low-temperature is 58.3°F (14.6°C).

Humidity

The average relative humidity in August is 76.3%.

Rainfall

The month with the least rainfall is August when the rain falls for 9.3 days and typically collects 3.1" (79.8mm) of precipitation.

Snowfall

In Portland, during the entire year, snow aggregates up to 61.9" (1572.3mm).

Ocean temperature

The month with the warmest seawater in Portland is August, with an average ocean temperature of 63.9°F (17.7°C).
Note: For swimming, a surface water temperature of 63.9°F (17.7°C) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 69.8°F (21°C).

Daylight

In August, the average length of the day is 13.9h.

Sunshine

In Portland, the average sunshine is 8.6h.

UV index

In Portland, Maine, the average daily maximum UV index is 7. A UV Index estimate of 6 to 7 represents a high health risk from the exposure to the Sun's UV rays for the average person.
Note: The daily maximum UV index of 7 in August interpret into the following advice:
Take precautions against overexposure. Protection against sun damage is needed. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.

What is the temperature in August in Portland?

In August, in Portland, Maine, the average high-temperature is 77.7°F (25.4°C), and the average low-temperature is 58.3°F (14.6°C).

What is the average humidity in August in Portland?

The average relative humidity in August in Portland is 76.3%.

How much does it rain in Portland in August?

In August, in Portland, the rain falls for 9.3 days. Throughout August, 3.1" (79.8mm) of precipitation is accumulated.

What is the driest month in Portland?

The month with the least rainfall is August when the rain falls for 9.3 days and typically collects 3.1" (79.8mm) of precipitation.

What is the month with the warmest ocean in Portland?

The month with the warmest seawater in Portland is August, with an average ocean temperature of 63.9°F (17.7°C).

What is the ocean temperature in August in Portland?

In August, the average ocean temperature is 63.9°F (17.7°C). For swimming, a surface water temperature of 63.9°F (17.7°C) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 69.8°F (21°C).

How many hours of daylight does Portland have in August?

In August, the average length of the day is 13.9h.

How many hours of sunshine does Portland have in August?

The average sunshine in August is 8.6h.

What is the UV index intensity in August in Portland?

The average daily maximum UV index in August in Portland is 7. A UV Index value of 6 to 7 symbolizes a high health risk from unsafe exposure to the Sun's UV rays.
Average temperature in August - Portland, ME
  • Average high temperature in August: 77.7°F

The warmest month (with the highest average high temperature) is July (78.8°F).
The month with the lowest average high temperature is January (31.2°F).

  • Average low temperature in August: 58.2°F

The month with the highest average low temperature is July (59.4°F).
The coldest month (with the lowest average low temperature) is January (13.4°F).

Average humidity in August - Portland, ME
  • Average humidity in August: 76.3%

The month with the highest relative humidity is September (76.7%).
The month with the lowest relative humidity is February (65.2%).

Average rainfall in August - Portland, ME
  • Average rainfall in August: 3.1"

Wettest months (with the highest rainfall) are October and November (4.9").
The driest month (with the lowest rainfall) is August (3.1").

Average rainfall days in August - Portland, ME
  • Average rainfall days in August: 9.3 days

The month with the highest number of rainy days is May (12.6 days).
The month with the lowest number of rainy days is September (9.2 days).

Average snowfall in August - Portland, ME
  • Average snowfall in August: 0"

The month with the highest snowfall is January (19.2").
Months with the lowest snowfall are May, June, July, August, September and October (0").

Average snowfall days in August - Portland, ME
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is January (7.9 days).
Months with the lowest number of snowfall days are May, June, July, August, September and October (0 days).

Average sea temperature in August - Portland, ME
  • Average sea temperature in August: 63.7°F

The best month for swimming (with the highest average sea temperature) is August (63.7°F).
The coldest month (with the lowest average sea temperature) is March (38°F).

Average daylight in August / Average sunshine in August - Portland, ME
  • Average daylight in August: 13.9h

The month with the longest days is June (Average daylight: 15.4h).
The month with shortest days is December (Average daylight: 9h).

  • Average sunshine in August: 8.6h

The month with most sunshine is July (Average sunshine: 9.1h).
The month with least sunshine is December (Average sunshine: 4.5h).

Average UV index in August - Portland, ME
  • Average UV index in August: 7

Months with the highest UV index are June and July (UV index 8).
Months with the lowest UV index are January and December (UV index 1).