Aurora Borealis in South Savo
Finland · 61.78°, 28.08° · geomagnetic 58.8° · needs Kp 5
Tonight in South Savo
40%
Peak chance of a visible display tonight, from the same model the Revon app runs. South Savo 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.
Get the full 30-night forecast in Revon
Updated 2026-09-08 10:35 UTC
How often the aurora borealis reaches South Savo
19.8 nights a year, averaged across 10.0 years of records
| Storm level | Nights / year |
|---|---|
| Kp 4 | 83.4 |
| Kp 5 | 28.7 |
| Kp 6 | 9.3 |
| Kp 7 | 3.2 |
| Kp 8 | 1.2 |
NOAA planetary Kp, 2016-04-02 to 2026-03-30
Worth watching through the dark half of the year
Kp 5 is a moderate storm — not an everyday event, but common enough that a patient observer in South Savo sees the aurora borealis most winters.
Hours of true darkness, month by month
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 12.2 | 10.2 | 7.4 | 1.6 | 0.0 | 0.0 | 0.0 | 0.0 | 5.8 | 9.3 | 11.7 | 12.7 |
Solar declination and hour angle at −18°
Nothing to see from May to August
Through those months the sun never falls more than 18° below the South Savo horizon, so the sky never darkens fully. Plan around the darker half of the year.
Getting clear of the light
The sky over South Savo reads Bortle 3. Getting clear of the built-up area makes a visible difference on a marginal night.
- 5 km south-west — around Juva → Bortle 3
- 5 km south-west — around Juva → Bortle 3
Falchi 2016 World Atlas (DOI: 10.5880/GFZ.1.4.2016.001)
The months that actually deliver
Counting only nights that were both stormy enough and dark enough, September, March and October came out ahead in South Savo. That is storm season and darkness overlapping — the equinoxes tend to be geomagnetically active, and the nights are already long by then.
Darkest nights of the coming year
A bright moon washes out a weak display as effectively as street lighting. These new moons fall inside the South Savo viewing season.
- 11 Sep 2026
- 11 Oct 2026
- 09 Nov 2026
- 09 Dec 2026
- 07 Jan 2027
- 06 Feb 2027
- 08 Mar 2027
Where it is close to a certainty
If you would rather plan a trip than wait for a storm, the nearest place with genuinely frequent aurora is Rovaniemi, 537 km north in Finland.
| South Savo | Rovaniemi | |
|---|---|---|
| Kp needed | 5 | 3 |
| Nights per year | 19.8 | 171.4 |
| Geomagnetic latitude | 58.8° | 63.6° |
Confirmed reports from this area
159 verified sightings were logged within 300 km of South Savo between 2015-01-01 and 2016-12-31. Rare is not the same as impossible.
Aurorasaurus verified positive reports
Where the horizon opens up near South Savo
The display sits low on the northern horizon, so what beats a better forecast is open ground facing that way. Height gets you above the town glow; water gives you an unbroken skyline. These are within a short drive of South Savo.
- Huutokallio — hill3.0 km north-north-east
- Kommelvuori — hill3.0 km north-east
- Kiviniemi — headland3.3 km north-north-east
- Salakkasaari — island3.5 km north-north-east
- Kalajärvi — lake3.7 km north-north-east
- Aittokorvenniemi — headland3.7 km north-north-west
Places from GeoNames (CC BY 4.0)
The last nights it was visible here
Nights in the last decade when the storm was strong enough for South Savo and the sky was dark enough to show it.
| Date | Peak |
|---|---|
| 2026-03-24 | Kp 5.0 |
| 2026-03-23 | Kp 5.0 |
| 2026-03-22 | Kp 6.67 |
| 2026-03-21 | Kp 6.0 |
| 2026-03-20 | Kp 7.0 |
NOAA planetary Kp
Aurora forecasts across South Savo
All 2 places in South Savo with a forecast page, and the Kp each one needs.
- MikkeliKp 5
- SavonlinnaKp 5
Know when it is worth going outside
Revon watches the South Savo forecast and pushes an alert when the odds for tonight clear your threshold — no checking, no guessing.
Common questions about the aurora borealis in South Savo
Can you see the aurora borealis from South Savo?
Yes. On the last 10.0 years of NOAA Kp records, South Savo had about 19.8 nights a year when the storm was strong enough and the sky dark enough at the same time.
What Kp index do you need to see the aurora borealis in South Savo?
Kp 5. South Savo sits at geomagnetic latitude 58.8°, and the auroral oval only reaches that far from the pole once activity hits Kp 5. Storms that size occur about 28.7 nights a year.
When is the best time of year to see the aurora borealis in South Savo?
September, March and October. Those months scored highest once both conditions are counted together: geomagnetic activity and enough hours of real darkness. From May to August the sky over South Savo never gets fully dark, so nothing is visible however strong the storm.
Where can you escape the light pollution near South Savo?
The centre of South Savo reads Bortle 3. The nearest sky at Bortle 3 is about 5 km south-west around Juva. On a marginal night that drive matters more than the forecast does.
Where is the nearest place to South Savo with reliable aurora borealis?
Rovaniemi, Finland — 537 km north. It needs only Kp 3 and averages 171.4 viable nights a year against 19.8 in South Savo.
Nearby towns
Forecasts for places within reach of South Savo.
- 🇫🇮 Savonlinna - Finland43 km
- 🇫🇮 Mikkeli - Finland44 km
- 🇫🇮 Varkaus - Finland61 km
- 🇫🇮 Imatra - Finland77 km
- 🇫🇮 Lappeenranta - Finland80 km
- 🇫🇮 Kouvola - Finland125 km
- 🇫🇮 Kuopio - Finland125 km
- 🇫🇮 Heinola - Finland126 km