Hafnarfjördur Weather in September
Hafnarfjördur in September sees moderate temperatures, with highs around 12°C (54°F) and overnight lows of 6°C (43°F). Rainfall is fairly high at around 146 mm (5.7 in) on average, so pack waterproofs just in case.
Rainfall in Hafnarfjördur in September
Expect around 18 days of rain based on historical data, with 146 mm (5.7 in) average. Expect frequent rainfall this month, and not just light drizzle. When it rains, it tends to come down hard.
Temperature in Hafnarfjördur in September
In September, Hafnarfjördur sees moderate temperatures, with highs of 12°C (54°F). Nights drop to around 6°C (43°F). Conditions are often most pleasant around the middle of the day. Nights drop to 6°C (43°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.
Sunshine in Hafnarfjördur in September
You can expect a moderate amount of sunlight, with approximately 121 hours. This means a pleasant mix of sun and overcast.
Wind Speed in Hafnarfjördur in September
Average wind conditions reach 5 m/s (10 knots) in September. This creates lively weather with fresh winds that make small trees sway noticeably. Remember this is an average: some days are less windy while others have particularly active windy conditions.
Average water temperature in September
With water temperatures around 10°C (50°F), swimming isn't really an option for most visitors. The cold sets in quickly and a wetsuit won't fully solve it.September in Hafnarfjördur has its charm. However, if you're seeking pleasant, dry and sunny weather, our weather planner can help you explore other destinations in the world.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Iceland, check out our Hafnarfjördur's climate page.
Hafnarfjördur Temperature in September
Min Temperature
6°C (43°F)
Max Temperature
12°C (54°F)
Water Temperature
10°C (50°F) *
Chance of Rain
60%
Precipitation
146 mm (5.7 in)
Rainy days
18 days
Humidity
79% *
Windspeed
5 m/s (10 knots) *
Sunshine
121 hours *
Percentage Sunshine
30% *
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Hafnarfjördur typically stay consistent throughout September, with daily highs averaging around 12°C (54°F). Nights are cold, with lows typically ranging from 4°C (39°F) to 8°C (46°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Hafnarfjördur in September
Browse day-by-day weather records for Hafnarfjördur spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Hafnarfjördur historical weather extremes in September
Based on 49 years of weather observations in Hafnarfjördur between 1976 and 2025, these are the recorded extremes.
- The hottest September day on record in Hafnarfjördur reached 18°C (64°F) (September 1, 2006).
- Hafnarfjördur experienced its chilliest September day on September 30, 1981, reaching only 3°C (37°F).
- The lowest overnight temperature recorded in September was -3°C (27°F) (September 25, 2005).
- Peak precipitation in September occurred on September 12, 2007, when 37 mm (1.5 in) of precipitation was measured.
Best Places in Iceland in September
Find out more about the weather in Iceland and which places have the best travel conditions in this month. See all of Iceland in September →
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What to Wear in Hafnarfjördur in September
The weather can be unpredictable in September, so pack clothes you can easily mix and match. You could bring jeans, other long pants, and a few t-shirts. A light jacket or light sweater will be pleasant for the cooler moments. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. Expect water temperatures of around 10°C (50°F), which is definitely too cold for comfortable swimming. Your luggage space is better used for other items. Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Hafnarfjördur in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Iceland, check out our Hafnarfjördur's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Hafnarfjördur climate overview or explore weather in Iceland.
