Aurora Borealis in Tumba

Sweden · 59.20°, 17.83° · geomagnetic 57.9° · needs Kp 7

Tonight in Tumba

37%

Peak chance of a visible display tonight, from the same model the Revon app runs. Tumba needs Kp 7 to see anything at all, and tonight the forecast peaks at Kp 5.7. Short of the threshold, which is what most nights look like here.

Tonight Sun 02 Aug
37%
18
20
22
00
02
04
06
Tomorrow Mon 3 Aug
3%
Hour-by-hour for this night is in the app
Tuesday Tue 4 Aug
2%
Hour-by-hour for this night is in the app

Unlock every hour in the app

Updated 2026-08-02 20:20 UTC

The next 30 nights in Tumba

Every night to come, scored the same way as tonight. The best of the open week is Sunday 2 Aug at 37%. Not one of the seven reaches the Kp 7 that Tumba needs, which is normal rather than unlucky — it averages 2.4 viable nights a year. The 23 nights past the seven-day window move with the 27-day solar rotation and are updated daily in the app.

Moderate aurora activity tonight around 11 PM. Similar conditions expected on August 19th.

Sun 2
37%
Kp 5.7
Mon 3
3%
Kp 3.3
Tue 4
2%
Kp 1.9
Wed 5
8%
Kp 3.0
Thu 6
3%
Kp 3.0
Fri 7
3%
Kp 2.0
Sat 8
2%
Kp 2.0

Nights 8–30 unlock in the Revon app

See all 30 nights for Tumba

Revon aurora model over the NOAA Kp forecast and 27-day outlook

How often the aurora borealis reaches Tumba

2.4 nights a year, averaged across 10.0 years of records

Storm levelNights / year
Kp 483.4
Kp 528.7
Kp 69.3
Kp 73.2
Kp 81.2

NOAA planetary Kp, 2016-04-02 to 2026-03-30

Wait for an alert; do not book a week

At Kp 7, Tumba needs a severe geomagnetic storm before anything shows above the northern horizon. Storms that size arrive a handful of times per solar cycle and announce themselves a day or two ahead. Watching for one beats picking dates and hoping.

Hours of true darkness, month by month

JanFebMarAprMayJunJulAugSepOctNovDec
12.010.27.83.50.00.00.00.06.49.511.612.5

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 Tumba horizon, so the sky never darkens fully. Plan around the darker half of the year.

Getting clear of the light

The sky over Tumba reads Bortle 9. Getting clear of the built-up area makes a visible difference on a marginal night.

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, November and March came out ahead in Tumba. 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 Tumba viewing season.

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, 903 km north-north-east in Finland.

TumbaRovaniemi
Kp needed73
Nights per year2.4 171.4
Geomagnetic latitude57.9° 63.6°

See the Rovaniemi forecast

Confirmed reports from this area

30 verified sightings were logged within 300 km of Tumba 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 Tumba

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 Tumba.

Places from GeoNames (CC BY 4.0)

What to do with the daylight

Aurora watching is a night job, and in winter that leaves a short, bright day to fill. Tumba keeps its fortified past above ground, at Ekängens skola, place of, Drottningholm Palace and Skansen, and for a day when the cloud sits low, Tom Tits Experiment and Lerkrogen are indoors and near by.

Keep the daylight loose: the sky decides the evening, and the forecast can turn within a few hours.

Places from GeoNames (CC BY 4.0)

Where to stay

Anywhere on the outskirts of Tumba will do; what matters is being able to step outside and check the sky without a drive first.

Places from GeoNames (CC BY 4.0) — confirm before booking

The last nights it was visible here

Nights in the last decade when the storm was strong enough for Tumba and the sky was dark enough to show it.

DatePeak
2026-03-20Kp 7.0
2026-01-20Kp 7.67
2026-01-19Kp 8.67
2025-11-12Kp 7.33
2025-11-11Kp 8.67

NOAA planetary Kp

Know when it is worth going outside

Revon watches the Tumba forecast and pushes an alert when the odds for tonight clear your threshold — no checking, no guessing.

Get aurora alerts on iPhone

Common questions about the aurora borealis in Tumba

Can you see the aurora borealis from Tumba?

Yes. On the last 10.0 years of NOAA Kp records, Tumba had about 2.4 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 Tumba?

Kp 7. Tumba sits at geomagnetic latitude 57.9°, and the auroral oval only reaches that far from the pole once activity hits Kp 7. Storms that size occur about 3.2 nights a year.

When is the best time of year to see the aurora borealis in Tumba?

September, November and March. 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 Tumba never gets fully dark, so nothing is visible however strong the storm.

Where can you escape the light pollution near Tumba?

The centre of Tumba reads Bortle 9. The nearest sky at Bortle 4 is about 44 km east-south-east around Haninge kommun. On a marginal night that drive matters more than the forecast does.

Where is the nearest place to Tumba with reliable aurora borealis?

Rovaniemi, Finland — 903 km north-north-east. It needs only Kp 3 and averages 171.4 viable nights a year against 2.4 in Tumba.

Nearby towns

Forecasts for places within reach of Tumba.