There is high pressure in the east and low pressure in the west. This means a southerly air flow with warm air is expected to move over the West Coast on Wednesday, according to SMHI's forecast.
This means temperatures could creep above 20 degrees again.
Locally it could be as high as 22 degrees. It's not a record we're talking about, but it's warmer than normal, says Amanda Bengtsson, meteorologist at SMHI.
The heat, with just over 20 degrees in some places, will persist until Thursday. Then it will be a little cooler for the weekend.
In the rest of Sweden, slightly lower temperatures are expected, but it will still be warm for the time of year.
At the same time, most of northern Sweden has already experienced meteorological autumn - that is, it has had an average daily temperature below 10 degrees for at least five days in a row.
Yes, in large parts of the northern half it is autumn. Even though there are some places where autumn hasn't really arrived up north either, says Amanda Bengtsson.
It is still quite warm during the day.
