Aurora Borealis in Hämeenlinna
Finland · 61.00°, 24.46° · geomagnetic 58.6° · needs Kp 5
Tonight's aurora forecast for Hämeenlinna
36%
Peak chance of a visible display tonight, from the same model the Revon app runs. Hämeenlinna needs Kp 5 to see anything at all, and tonight the forecast peaks at Kp 4.7. Short of the threshold, which is what most nights look like here.
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Updated 2026-09-08 10:35 UTC
Local aurora guide for Hämeenlinna
Aurora activity is measured by the Kp index, with Kp 5 considered the minimum for viewing in Hämeenlinna. This level of activity occurs on approximately 20.1 nights per year.
The geomagnetic latitude of Hämeenlinna is 58.6°.
The best months for aurora viewing in Hämeenlinna are September, March, and October. During these months, there are sufficient hours of darkness.
From May through August, the region experiences periods without full darkness, which can impact viewing opportunities.
Hämeenlinna is classified as Bortle 5, indicating a suburban sky brightness. Areas with darker skies, such as Bortle 3, can be found nearby.
Several locations offer varied horizons. Kilometrimäki, a hill 3.0 km north of Hämeenlinna, provides a northern horizon. Aulanko Nature Reserve, 3.1 km north, and Molkkarinmäki, a hill 3.1 km north-north-west, also offer viewing potential.
Kilometrimäki is a hill located 3.0 km north of Hämeenlinna. Aulanko Nature Reserve is situated 3.1 km north of the city.
Molkkarinmäki, a hill 3.1 km north-north-west of Hämeenlinna, and Aulangonniemi, a headland 3.2 km north, are also noted geographical features.
Lusikkaniemi, a headland 3.2 km north-east of Hämeenlinna, offers another potential vantage point.
Between 2016 and 2026, there were multiple nights with Kp values of 5.0 or higher, indicating potential aurora visibility. These include nights with Kp values ranging from 5.0 to 7.0.
Historical records show 41 verified aurora reports within a 300 km radius of Hämeenlinna between January 2015 and December 2016.
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
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Forecasts for places within reach of Hämeenlinna.