Hauts-de-France

Northern lights in Calais tonight

Real-time aurora forecast for Calais (Hauts-de-France) - latitude 50.95° N, estimated Kp threshold 7.

Kp index

4.3

unsettled

Hemispheric power

North21GW

South22GW

Source: app.pulsar-si.com

Tonight in Calais

Very unlikely

Based on Kp 4.3 and Calais's latitude.

Seeing the northern lights from Calais

Calais, at almost 51° N, is among the most northerly continental French cities. Auroras are more accessible here: Kp 5-6 is enough. The coastal position on the Strait of Dover offers a northern horizon open to the sea. The May 2024 storm enabled exceptional observations from Cap Blanc-Nez, but more moderate auroras are regularly visible.

Observation conditions in Calais

Bortle 7 in the centre, but the Opal Coast (Bortle 4-5, 5-15 km north) and the Blanc-Nez and Gris-Nez capes offer a perfect horizon over the Channel. The Audomarois marshes, 30 km away, drop to Bortle 4. The oceanic climate brings frequent cloud passes - observation windows are shorter than inland.

Recent auroras from Calais

10-11 May 2024 (Kp 9): intense aurora observed from Cap Blanc-Nez, naked-eye green and red. 5 November 2023 (Kp 7): sightings from the Opal Coast. 27 February 2023 (Kp 6): confirmed observations. 23 March 2023 (Kp 7): aurora reported from Wissant.

What Calais asks of the sky

Geomagnetic latitude

52.5°

1 of 40

Kp index required

Kp 7

9 / 12 months

Dark nights per year

312

-53

Calais ranks 1 of the 40 cities we track, at 52.5° geomagnetic. No tracked city sits higher , Dunkerque follows at 52.5°.

The threshold to clear here is Kp 7. Twelve months of archive hold 9 nights, the most recent on 4 July 2026, and 157 since 1994. Dunkerque and Lille and Amiens share exactly the same threshold.

A constraint specific to this latitude: astronomical night disappears from 27 mai to 18 juillet. Those 53 nights are lost in advance, whatever the Sun does. That leaves 312 usable nights.

How to read the Kp index →

Local conditions

Light pollution

Bortle 7 of 9

SQM 18.56 mag/arcsec²

Nearest darker sky

Calais

2 km · Bortle 3

Kp forecast, next 3 days

Source: app.pulsar-si.com. For an aurora to be visible from Calais, Kp must exceed 7.

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 Calais?

Yes, but rarely. Typically a Kp index of ≥ 7 is needed for the aurora to become visible from Calais (latitude 51.0° 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 Calais?

The approximate Kp threshold for Calais is 7. Below that, auroras stay confined to high latitudes (Norway, Scotland). Above it, they gradually extend southward. A Kp of 8 gives a fair chance, 9 a strong one.

When is the best time to watch from Calais?

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 Calais offers better conditions?

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

Nearby cities

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