Aurora Borealis in Norrtälje
Sweden · 59.76°, 18.70° · geomagnetic 58.3° · needs Kp 5
Tonight's aurora forecast for Norrtälje
45%
Peak chance of a visible display tonight, from the same model the Revon app runs. Norrtälje needs Kp 5 to see anything at all, and tonight the forecast peaks at Kp 4.8. Short of the threshold, which is what most nights look like here.
Get the full 30-night forecast in Revon
Updated 2026-09-08 10:35 UTC
Local aurora guide for Norrtälje
The aurora forecast uses a Kp 5 threshold. This is the minimum geomagnetic activity level needed to see the aurora from Norrtälje.
At 58.3° geomagnetic latitude, Norrtälje sees about 21.0 viable nights per year. These are nights when the aurora may be visible.
The record span for this data is from April 2, 2016, to March 30, 2026.
The best months for aurora viewing in Norrtälje are September, March, and October.
During May, June, July, and August, there is no full darkness, which can make aurora viewing difficult.
Norrtälje has a Bortle 4 rating, indicating a dark sky. Areas near Norrtälje kommun are also Bortle 4.
The horizon is relatively clear in several directions. Malstasjön is 4.1 km west-north-west, Gillfjärden is 4.2 km north-east, and Mörjarudden is 7.3 km east.
Malstasjön is a lake located 4.1 km west-north-west of Norrtälje.
Gillfjärden is a lake situated 4.2 km north-east of Norrtälje.
Mörjarudden is a headland 7.3 km east of Norrtälje. Enholmen, an island, is 7.7 km east-north-east, and Tisterudden, another headland, is 11.1 km east.
There have been 29 verified aurora reports within 300 km of Norrtälje between January 1, 2015, and December 31, 2016.
The data indicates that nights with Kp 5.0 or higher occurred on March 20-24, 2026, and March 20-24, 2026.
Sources: Revon location dataset · Revon analysis of NOAA planetary Kp · Solar declination and hour-angle calculation · Falchi 2016 World Atlas of artificial night sky brightness · GeoNames (CC BY 4.0) · Aurorasaurus verified positive reports
Know when it is worth going outside
Revon watches the Norrtälje forecast and pushes an alert when the odds for tonight clear your threshold — no checking, no guessing.
Nearby towns
Forecasts for places within reach of Norrtälje.