Pays de la Loire

Northern lights in Nantes tonight

Real-time aurora forecast for Nantes (Pays de la Loire) - latitude 47.22° N, estimated Kp threshold 8.

Kp index

4.3

unsettled

Hemispheric power

North21GW

South22GW

Source: app.pulsar-si.com

Tonight in Nantes

Very unlikely

Based on Kp 4.3 and Nantes's latitude.

Seeing the northern lights from Nantes

Nantes, at 47.2° N, benefits from its position on the Atlantic façade to offer a clear northern horizon over the Loire and the Pays de Retz plain. The oceanic climate generates frequent cloud cover though, which complicates observation. Auroras become visible around Kp 6.5-7. The May 2024 storm produced a particularly photogenic show thanks to clear skies that night, with red auroras from the Loire embankments.

Observation conditions in Nantes

Central Nantes is rated Bortle 7. At 30 km, the Clisson countryside and the marshes of Grand-Lieu drop to Bortle 4. For a truly starry sky, head to the Groulais forest (north of the Loire, 50 km) or the south coast of Loire-Atlantique (Bortle 3-4, 60 km). Sea breezes and passing clouds are the main constraint: check cloud cover the day before.

Recent auroras from Nantes

10-11 May 2024 (Kp 9): spectacular red and green aurora, photographed from the Loire embankments and the Cheviré bridge. Nantes was among the major French cities with the best images that night, thanks to a clear sky. 5 November 2023 (Kp 7): rural sightings.

What Nantes asks of the sky

Geomagnetic latitude

49.4°

19 of 40

Kp index required

Kp 8

2 / 12 months

Dark nights per year

365

365 / 365

Nantes ranks 19 of the 40 cities we track, at 49.4° geomagnetic. Nancy sits 0.2° higher , Strasbourg follows at 49.3°.

The threshold to clear here is Kp 8. Twelve months of archive hold 2 nights, the most recent on 19 January 2026, and 48 since 1994. In Rennes, Kp 7 is already enough.

Nantes keeps full astronomical night all 365 nights of the year, which every city north of the Loire loses for part of the summer.

How to read the Kp index →

Local conditions

Light pollution

Bortle 8 of 9

SQM 18.28 mag/arcsec²

Nearest darker sky

Decré

2 km · Bortle 6

Kp forecast, next 3 days

Source: app.pulsar-si.com. For an aurora to be visible from Nantes, Kp must exceed 8.

Wed 19 Aug

1.1

Expected max Kp

Thu 20 Aug

1.5

Expected max Kp

Fri 21 Aug

1.7

Expected max Kp

Frequently asked questions

Can you see the northern lights from Nantes?

Yes, but rarely. Typically a Kp index of ≥ 8 is needed for the aurora to become visible from Nantes (latitude 47.2° N). Major geomagnetic storms (Kp 8-9) that reach this latitude happen only a handful of times per 11-year solar cycle.

What Kp index is needed to see auroras from Nantes?

The approximate Kp threshold for Nantes is 8. Below that, auroras stay confined to high latitudes (Norway, Scotland). Above it, they gradually extend southward. A Kp of 9 gives a fair chance, 10 a strong one.

When is the best time to watch from Nantes?

Auroras are a nighttime phenomenon, best observed between roughly 10 PM and 2 AM local time, when the geomagnetic pole is tilted towards the Earth's night side. In practice, peaks depend on when a coronal mass ejection arrives - activity can spike at any hour.

Where around Nantes offers better conditions?

Move at least 40-60 km north of Nantes to escape urban light pollution and gain 1-2 magnitudes of limiting magnitude.

Nearby cities

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