United Kingdom

Northern lights in England tonight

The aurora reaches England at about Kp 5.6 in its far north. SWPC forecasts a highest Kp of 2 over the next three days, in the 03-06 UTC block on Mon, Sep 21, which falls short of it.

From NOAA’s Space Weather Prediction Center, read Sep 20, 15:50 UTC.

Towns in England

Most poleward first, with the Kp each needs and its forecast page.

Kp by 3-hour block

SWPC’s planetary K index forecast, three days ahead. Kp is a single number for the whole planet, from magnetometers around the world, on a scale of 0 to 9 in thirds.

Block (UTC)	Kp	Level	Seen from	Central US
15-18	1.00	Quiet	65° geomag.	57°N
18-21	1.33	Quiet	64° geomag.	56°N
21-00	1.33	Quiet	64° geomag.	56°N
00-03	1.67	Quiet	64° geomag.	56°N
03-06	2.00	Quiet	64° geomag.	55°N
06-09	1.67	Quiet	64° geomag.	56°N
09-12	1.33	Quiet	64° geomag.	56°N
12-15	0.67	Quiet	65° geomag.	57°N
15-18	1.33	Quiet	64° geomag.	56°N
18-21	1.33	Quiet	64° geomag.	56°N
21-00	1.67	Quiet	64° geomag.	56°N
00-03	1.67	Quiet	64° geomag.	56°N
03-06	1.33	Quiet	64° geomag.	56°N
06-09	1.33	Quiet	64° geomag.	56°N
09-12	1.33	Quiet	64° geomag.	56°N
12-15	1.33	Quiet	64° geomag.	56°N
15-18	1.33	Quiet	64° geomag.	56°N
18-21	1.67	Quiet	64° geomag.	56°N
21-00	1.67	Quiet	64° geomag.	56°N
00-03	1.67	Quiet	64° geomag.	56°N

The forecast is for the planet, not for your sky. A block at Kp 5 means the field is disturbed enough for the aurora to reach 60 degrees geomagnetic somewhere along the night side; whether you see it depends on being on the night side, on darkness, and on the clouds.

What this means

Each place is placed by its geomagnetic latitude, measured from the geomagnetic dipole pole, and compared with the reach NOAA states for each storm level on its space weather scales: G1 (Kp 5) about 60 degrees geomagnetic, G2 55, G3 50, G4 45, G5 (Kp 9) 40. Reading that backwards gives the Kp a place needs. Below Kp 5 the oval contracts more slowly and the line runs from 66 degrees at Kp 0 to 60 at Kp 5.

The forecasts have different horizons and the pages keep them apart: OVATION is the only thing that knows whether an aurora is out now, and it reaches 30 to 90 minutes ahead; the planetary Kp forecast runs three days; the 27-day outlook names likely active days and is not a forecast of any one night. None of them knows the clouds, which is why a town page reads its own forecast for those.

Sources

From NOAA’s Space Weather Prediction Center: the OVATION aurora forecast, the planetary K index forecast, the 3-day forecast, the 27-day outlook, its watches, warnings and alerts, and the real-time solar wind. Read Sep 20, 15:50 UTC.

Aurora forecast By country Live radar