Stykkishólmur Weather in September
September in Stykkishólmur sees daytime temperatures around 11°C (52°F) and lows of 7°C (45°F) at night. As the wettest month of the year, keep in mind that rainfall is at its highest.
Rainfall in Stykkishólmur in September
Since this month has the highest rainfall, keep an umbrella with you to handle sudden showers. You can typically expect 16 days of rain this month, averaging around 135 mm (5.3 in). This is a wet month with frequent and often heavy showers. Both the number of rain days and the total rainfall are high.
Temperature in Stykkishólmur in September
Temperatures in Stykkishólmur in September top out at 11°C (52°F) and drop to 7°C (45°F) overnight. Temperatures remain on the cold side all day. A proper warm jacket is worth having, not just for evenings. With overnight lows of 7°C (45°F), nights are cold. The cold air does make for deep, comfortable sleep if you have enough blankets.
Sunshine in Stykkishólmur in September
With about 106 hours of sunshine, the area enjoys a nice balance of sun and overcast, creating a pleasant environment.
Wind Speed in Stykkishólmur in September
Wind speeds average 6 m/s (12 knots) during September. At this speed, expect strong winds that make large branches move and create some resistance when walking. Since this is an average, some days have fresh winds while others have strong breezes that can make umbrellas tricky to control.
Average water temperature in September
The water temperature is only 9°C (48°F) this month — cold enough that most people will want to stay out. Hardy swimmers may manage a quick dip, but it won't be comfortable.September in Stykkishólmur has its charm, but if you're looking for destinations with pleasant temperatures and sunny skies, our weather planner can help you explore other options 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 Stykkishólmur's climate page.
Stykkishólmur Temperature in September
Min Temperature
7°C (45°F)
Max Temperature
11°C (52°F)
Water Temperature
9°C (48°F)
Chance of Rain
53%
Precipitation
135 mm (5.3 in)
Rainy days
16 days
Humidity
79%
Windspeed
6 m/s (12 knots)
Sunshine
106 hours
Percentage Sunshine
27%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Stykkishólmur typically drop from around 11°C (52°F) at the start of September to approximately 8°C (46°F) by the end. Nights are cold, with lows typically ranging from 3°C (37°F) to 7°C (45°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 Stykkishólmur in September
Browse day-by-day weather records for Stykkishólmur spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Stykkishólmur historical weather extremes in September
Based on 29 years of weather observations in Stykkishólmur between 1996 and 2025, these are the recorded extremes.
- The hottest September day on record in Stykkishólmur reached 18°C (64°F) (September 3, 2010).
- On September 23, 2005, Stykkishólmur saw its coldest September day with temperatures maxing out at 3°C (37°F).
- Nighttime temperatures dropped to -5°C (23°F) on September 26, 2024, marking the coldest September night on record.
- The wettest day in September Stykkishólmur was on September 19, 2019 with 68 mm (2.7 in) of precipitation.
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 Stykkishólmur 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. With water temperatures around 9°C (48°F), the water is quite cold for swimming. You can skip the swimwear unless you're particularly tough. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.What To Do in Stykkishólmur 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 Stykkishólmur's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Stykkishólmur climate overview or explore weather in Iceland.
