Portsmouth
Virginia, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Portsmouth, VA

A high view of gold and brown trees and modern and developed buildings in Downtown Portsmouth, Virginia, glorious cloudy sky lighting up the city
A high view of gold and brown trees and modern and developed buildings in Downtown Portsmouth, Virginia, glorious cloudy sky lighting up the city
September, the first month of the autumn, in Portsmouth, is also a moderately hot month, with average temperature fluctuating between 79.3°F (26.3°C) and 65.3°F (18.5°C).

Temperature

In Portsmouth, the average high-temperature in September slightly decreases, from a moderately hot 85.1°F (29.5°C) in August, to a still warm 79.3°F (26.3°C). In Portsmouth, in September, the average low-temperature is 65.3°F (18.5°C).

Humidity

The average relative humidity in Portsmouth, Virginia, is 74.4%.

Rainfall

In Portsmouth, in September, it is raining for 8.8 days, with typically 4.8" (120.9mm) of accumulated precipitation. In Portsmouth, during the entire year, the rain falls for 117 days and collects up to 46.5" (1181.9mm) of precipitation.

Snowfall

In Portsmouth, during the entire year, snow aggregates up to 5.8" (147.4mm).

Ocean temperature

In September, the average ocean temperature in Portsmouth is 75.6°F (24.2°C). For individuals prone to feeling cold, swimming in 73.4°F (23°C) is still regarded as intolerable. A wetsuit is not a necessity, but sunshine, wind, and air temperature are essential factors for relishing swimming at 75.6°F (24.2°C).

Daylight

In September, the average length of the day in Portsmouth is 12.4h.

Sunshine

In Portsmouth, the average sunshine in September is 7.7h.

What is the temperature in September in Portsmouth?

In September, the average high-temperature is 79.3°F (26.3°C), and the average low-temperature is 65.3°F (18.5°C).

What is the average humidity in September in Portsmouth?

The average relative humidity in September is 74.4%.

How many days does it rain in September in Portsmouth?

In Portsmouth, Virginia, in September, it is raining for 8.8 days, with typically 4.8" (120.9mm) of accumulated precipitation.

What is the ocean temperature in September in Portsmouth?

In Portsmouth, the average seawater temperature in September is 75.6°F (24.2°C). For individuals prone to feeling cold, swimming in 73.4°F (23°C) is still regarded as intolerable. A wetsuit is not a necessity, but sunshine, wind, and air temperature are essential factors for relishing swimming at 75.6°F (24.2°C).

What is the average length of the day in September in Portsmouth?

In September, the average length of the day in Portsmouth, Virginia, is 12.4h.

How many hours of sunshine does Portsmouth have in September?

In September, the average sunshine in Portsmouth is 7.7h.
Average temperature in September - Portsmouth, VA
  • Average high temperature in September: 79.3°F

The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (48.1°F).

  • Average low temperature in September: 65.3°F

The month with the highest average low temperature is July (71.9°F).
The coldest month (with the lowest average low temperature) is January (32.7°F).

Average humidity in September - Portsmouth, VA
  • Average humidity in September: 74.4%

The month with the highest relative humidity is August (75.2%).
The month with the lowest relative humidity is April (62.8%).

Average rainfall in September - Portsmouth, VA
  • Average rainfall in September: 4.8"

The wettest month (with the highest rainfall) is August (5.5").
The driest month (with the lowest rainfall) is February (3.1").

Average rainfall days in September - Portsmouth, VA
  • Average rainfall days in September: 8.8 days

The month with the highest number of rainy days is July (11.1 days).
The month with the lowest number of rainy days is October (7.6 days).

Average snowfall in September - Portsmouth, VA
  • Average snowfall in September: 0"

The month with the highest snowfall is January (2.4").
Months with the lowest snowfall are April, May, June, July, August, September, October and November (0").

Average snowfall days in September - Portsmouth, VA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (1.6 days).
Months with the lowest number of snowfall days are May, June, July, August, September, October and November (0 days).

Average sea temperature in September - Portsmouth, VA
  • Average sea temperature in September: 75.6°F

The best month for swimming (with the highest average sea temperature) is August (80°F).
The coldest month (with the lowest average sea temperature) is February (44.5°F).

Average daylight in September / Average sunshine in September - Portsmouth, VA
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 14.7h).
The month with shortest days is December (Average daylight: 9.7h).

  • Average sunshine in September: 7.7h

The month with most sunshine is June (Average sunshine: 9.3h).
The month with least sunshine is December (Average sunshine: 5.2h).