The city is located in northern Sweden, in the province of Norrbotten, in the northernmost part of the Gulf of Bothnia (called Bottenviken), which in winter can freeze. It is useful to recall that the sea water freezes at about -2 °C (28.5 °F).
Since we are at the 65th parallel, therefore south of the Arctic Circle, you cannot see the
, however, it's enough to go 30 km (18 mi) to the north, in Boden, to see the midnight sun from June 17th to June 26th. The
, when the sun sets but it doesn't get completely dark even at midnight, occur in Luleå from April 24 to August 20. In December, at noon, the sun is just above the horizon.
drops for a few days to -25 °C (-13 °F), but in the coldest winters it can go down to -35/-36 °C (-33/-31 °F), as happened in 1985, 1987 and 2012. The cold record, -41 °C (-42 °F), was set in January 1999.
, the temperature can reach 28/30 °C (82/86 °F) on the hottest days, but this happens very rarely. The highest record is 34.6 °C (94.3 °F) and was set in July 1945.
In summer, also due to the length of the days, the sunshine amount is quite good, and definitely better than in Norway.
, from June to August, since it is the mildest season. However, you must take into account some rainy days and a bit of cold at night.
. Here are the average temperatures.
January is generally a freezing cold month. The average temperature is of
-8.7 °C, with a minimum of
-12.8 °C and a maximum of
-4.6 °C.

On the coldest nights of the month, the temperature usually drops to around
-26.5 °C. However, it dropped to
-41 °C in January 1999.

On the warmest days of the month, the temperature usually reaches around
5 °C. However, it reached
9 °C in January 1992.

Precipitation amounts to
50 mm, distributed over 10 days.
The day lasts on average 4 hours and 55 minutes. So the days are short.

There are on average 0.5 hours of sunshine per day. So, the sun shines 15% of the time.
The average humidity is 86%. Hence, the air is normally humid.
The average wind speed is of
11.6 kph.

The average sea temperature is of
0.6 °C. Therefore, the sea is very cold for swimming.
February, the coldest month of the year, is generally a freezing cold month. The average temperature is of
-9.1 °C, with a minimum of
-13.4 °C and a maximum of
-4.8 °C.

On the coldest nights of the month, the temperature usually drops to around
-25.5 °C. However, it dropped to
-35 °C in February 1994.

On the warmest days of the month, the temperature usually reaches around
5.5 °C. However, it reached
10 °C in February 1993.

Precipitation amounts to
35 mm, distributed over 9 days.
The day lasts on average 8 hours and 25 minutes.

There are on average 3 hours of sunshine per day. So, the sun shines 33% of the time.
The average humidity is 85%. Hence, the air is normally humid.
The average wind speed is of
11.5 kph.

The average sea temperature is of
-0.4 °C. Therefore, the sea is very cold for swimming.
March is generally a very cold month. The average temperature is of
-4.4 °C, with a minimum of
-8.8 °C and a maximum of
0 °C.

On the coldest nights of the month, the temperature usually drops to around
-20.5 °C. However, it dropped to
-29 °C in March 1994.

On the warmest days of the month, the temperature usually reaches around
9 °C. However, it reached
13.4 °C in March 2016.

Precipitation amounts to
30 mm, distributed over 8 days.
The day lasts on average 11 hours and 55 minutes.

There are on average 5.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is of
12.4 kph.

The average sea temperature is of
-0.6 °C. Therefore, the sea is very cold for swimming.
April is generally a cold month. The average temperature is of
1 °C, with a minimum of
-3.1 °C and a maximum of
5.1 °C.

On the coldest nights of the month, the temperature usually drops to around
-11 °C. However, it dropped to
-17 °C in April 1993.

On the warmest days of the month, the temperature usually reaches around
12.5 °C. However, it reached
18.4 °C in April 2019.

Precipitation amounts to
30 mm, distributed over 7 days.
The day lasts on average 15 hours and 30 minutes.

There are on average 7.5 hours of sunshine per day. So, the sun shines 48% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is of
11.5 kph.

The average sea temperature is of
0.1 °C. Therefore, the sea is very cold for swimming.
May is generally a quite mild month. The average temperature is of
7.3 °C, with a minimum of
2.7 °C and a maximum of
11.8 °C.

On the coldest nights of the month, the temperature usually drops to around
-3.5 °C. However, it dropped to
-6.4 °C in May 1999.

On the warmest days of the month, the temperature usually reaches around
20.5 °C. However, it reached
28.4 °C in May 2009.

Precipitation amounts to
40 mm, distributed over 7 days.
The day lasts on average 19 hours and 10 minutes. So the days are very long.

There are on average 9 hours of sunshine per day. So, the sun shines 48% of the time.
The average humidity is 66%.
The average wind speed is of
12.2 kph.

The average sea temperature is of
2.7 °C. Therefore, the sea is very cold for swimming.
June is generally a mild month. The average temperature is of
13 °C, with a minimum of
8.8 °C and a maximum of
17.2 °C.

On the coldest nights of the month, the temperature usually drops to around
3 °C. However, it dropped to
0.3 °C in June 2017.

On the warmest days of the month, the temperature usually reaches around
25 °C. However, it reached
30 °C in June 2011.

Precipitation amounts to
60 mm, distributed over 8 days.
The day lasts on average 22 hours and 30 minutes. So the days are very long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.

There are on average 10 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 66%.
The average wind speed is of
12.5 kph.

The average sea temperature is of
7.5 °C. Therefore, the sea is very cold for swimming.
July, the warmest month of the year, is generally a very mild month. The average temperature is of
16.5 °C, with a minimum of
12.4 °C and a maximum of
20.5 °C.

On the coldest nights of the month, the temperature usually drops to around
7.5 °C. However, it dropped to
4.7 °C in July 2010.

On the warmest days of the month, the temperature usually reaches around
26.5 °C. However, it reached
32.1 °C in July 2003.

Precipitation amounts to
60 mm, distributed over 8 days.
The day lasts on average 20 hours and 25 minutes. So the days are very long.

There are on average 10 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is of
11.9 kph.

The average sea temperature is of
13.1 °C. Therefore, the sea is very cold for swimming.
August is generally a very mild month. The average temperature is of
14.6 °C, with a minimum of
10.9 °C and a maximum of
18.4 °C.

On the coldest nights of the month, the temperature usually drops to around
4 °C. However, it dropped to
1 °C in August 1995.

On the warmest days of the month, the temperature usually reaches around
24 °C. However, it reached
28.9 °C in August 2002.

Precipitation amounts to
70 mm, distributed over 9 days.
The day lasts on average 16 hours and 30 minutes. So the days are long.

There are on average 8 hours of sunshine per day. So, the sun shines 48% of the time.
The average humidity is 77%. Hence, the air is normally humid.
The average wind speed is of
11.6 kph.

The average sea temperature is of
14.6 °C. Therefore, the sea is very cold for swimming.
September is generally a mild month. The average temperature is of
9.5 °C, with a minimum of
5.9 °C and a maximum of
13.1 °C.

On the coldest nights of the month, the temperature usually drops to around
-1.5 °C. However, it dropped to
-4.1 °C in September 2018.

On the warmest days of the month, the temperature usually reaches around
19 °C. However, it reached
23 °C in September 2002.

Precipitation amounts to
60 mm, distributed over 8 days.
The day lasts on average 13 hours and 0 minutes.

There are on average 5 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is of
12.2 kph.

The average sea temperature is of
12 °C. Therefore, the sea is very cold for swimming.
October is generally a cold month. The average temperature is of
2.7 °C, with a minimum of
-0.3 °C and a maximum of
5.8 °C.

On the coldest nights of the month, the temperature usually drops to around
-10 °C. However, it dropped to
-18 °C in October 1992.

On the warmest days of the month, the temperature usually reaches around
13 °C. However, it reached
17 °C in October 1995.

Precipitation amounts to
50 mm, distributed over 9 days.
The day lasts on average 9 hours and 30 minutes.

There are on average 3 hours of sunshine per day. So, the sun shines 31% of the time.
The average humidity is 85%. Hence, the air is normally humid.
The average wind speed is of
11.9 kph.

The average sea temperature is of
8.2 °C. Therefore, the sea is very cold for swimming.
November is generally a very cold month. The average temperature is of
-2.9 °C, with a minimum of
-5.9 °C and a maximum of
0.2 °C.

On the coldest nights of the month, the temperature usually drops to around
-16.5 °C. However, it dropped to
-25 °C in November 1992.

On the warmest days of the month, the temperature usually reaches around
7 °C. However, it reached
12 °C in November 2004.

Precipitation amounts to
55 mm, distributed over 10 days.
The day lasts on average 5 hours and 55 minutes. So the days are short.

There is an average of 1 hour of sunshine per day. So, the sun shines 21% of the time.
The average humidity is 90%. Hence, the air is normally humid.
The average wind speed is of
11.7 kph.

The average sea temperature is of
4.9 °C. Therefore, the sea is very cold for swimming.
December is generally a freezing cold month. The average temperature is of
-6.5 °C, with a minimum of
-10.2 °C and a maximum of
-2.8 °C.

On the coldest nights of the month, the temperature usually drops to around
-23 °C. However, it dropped to
-32.2 °C in December 1995.

On the warmest days of the month, the temperature usually reaches around
5.5 °C. However, it reached
8.5 °C in December 2013.

Precipitation amounts to
50 mm, distributed over 11 days.
The day lasts on average 3 hours and 25 minutes. So the days are very short. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.

There are on average 0 hours of sunshine per day. So, the sun shines 3% of the time.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is of
11.4 kph.

The average sea temperature is of
2.4 °C. Therefore, the sea is very cold for swimming.