☽︎Sky and Signs

Northern lights forecast: the next three days

Highest predicted Kp in the next three days: 4.7 on Mon 19.10.

Aurora appears when a storm of charged particles from the Sun shakes the Earth's magnetic field. The Kp index measures how strongly, from 0 to 9. In northern Scandinavia almost any value will do; Scotland needs about Kp 4, London 6, New York 6 or more. The forecast comes from NOAA's Space Weather Prediction Center and is loaded fresh when you open the page.

Kp forecast in three-hour blocks

Times in UTC

0003060912151821Mon 19.10.3.03.74.74.3Tue 20.10.4.34.73.73.03.03.03.33.7Wed 21.10.3.33.73.02.72.32.03.33.0Thu 22.10.2.7

Where it could reach

PlaceNeedsNext three days
TromsøKp 0possible on Mon 19.10.
ReykjavíkKp 0possible on Mon 19.10.
RovaniemiKp 0possible on Mon 19.10.
FairbanksKp 0possible on Mon 19.10.
AnchorageKp 1possible on Mon 19.10.
YellowknifeKp 0possible on Mon 19.10.
InvernessKp 3possible on Mon 19.10.
EdinburghKp 4possible on Mon 19.10.
BelfastKp 5borderline
ManchesterKp 5borderline
DublinKp 5borderline
LondonKp 6unlikely
SeattleKp 4possible on Mon 19.10.
MinneapolisKp 4possible on Mon 19.10.
ChicagoKp 5borderline
TorontoKp 4possible on Mon 19.10.
New YorkKp 6unlikely
HobartKp 4possible on Mon 19.10.
MelbourneKp 6unlikely
ChristchurchKp 5borderline
DunedinKp 4possible on Mon 19.10.

How to see it

It has to be dark and clear, with an open view towards the pole: north in the northern hemisphere, south in the southern, away from city lights. At mid latitudes aurora usually sits low on the horizon as a green or red glow; the eye often sees it grey, a phone camera in night mode shows the colours. Kp is a three-hour average: a short burst can bring more, a quiet spell less. The values in the table are a rule of thumb for a camera at the horizon.

On 10 May 2024 a storm reached Kp 9: aurora was seen across Europe and the United States, as far south as Spain and Florida.