Northern Lights Portland – Visible Tonight? Kp 5.7 Needed

From Kp 5.7 the aurora can be seen on the horizon in Portland, from Kp 7.7 high in the sky. NOAA's live 3-day Kp forecast and tonight's dark hours.

Aurora over Portland

  • Portland lies at 51° geomagnetic latitude. From Kp 5.7 an aurora can show low over the northern horizon, from Kp 7.7 it can reach overhead – on a dark, clear night away from city lights.

Dark hours in Portland – the next 7 nights

  • Sun, November 8: fully dark from 18:29 to 05:19, moon 0 % lit
  • Mon, November 9: fully dark from 18:28 to 05:21, moon 0 % lit
  • Tue, November 10: fully dark from 18:27 to 05:22, moon 2 % lit
  • Wed, November 11: fully dark from 18:26 to 05:23, moon 6 % lit
  • Thu, November 12: fully dark from 18:25 to 05:24, moon 11 % lit
  • Fri, November 13: fully dark from 18:24 to 05:25, moon 18 % lit
  • Sat, November 14: fully dark from 18:23 to 05:26, moon 26 % lit

Which Kp is enough where?

  • Reykjavik: On the horizon from Kp 0 · High in the sky from Kp 0
  • Tromsø: On the horizon from Kp 0 · High in the sky from Kp 0
  • Edinburgh: On the horizon from Kp 2 · High in the sky from Kp 4
  • Oslo: On the horizon from Kp 1.3 · High in the sky from Kp 3.3
  • Stockholm: On the horizon from Kp 2.3 · High in the sky from Kp 4
  • Helsinki: On the horizon from Kp 2.3 · High in the sky from Kp 4.3
  • Copenhagen: On the horizon from Kp 3.3 · High in the sky from Kp 5.3
  • Hamburg: On the horizon from Kp 4.3 · High in the sky from Kp 6.3
  • Berlin: On the horizon from Kp 5 · High in the sky from Kp 7
  • London: On the horizon from Kp 4.3 · High in the sky from Kp 6.3
  • Warsaw: On the horizon from Kp 5.7 · High in the sky from Kp 7.7
  • Munich: On the horizon from Kp 7 · High in the sky from Kp 9
  • Paris: On the horizon from Kp 6 · High in the sky from Kp 8
  • Toronto: On the horizon from Kp 4.7 · High in the sky from Kp 6.7
  • Data: NOAA Space Weather Prediction Center

How long it gets fully dark in Portland

  • The night after the 15th of each month: how long the sun stays more than 18° below the horizon. An aurora needs that dark sky – far north, summer has none at all.
  • January: 11 h 22 min · 18:39–06:01
  • February: 10 h 14 min · 19:17–05:31
  • March: 8 h 46 min · 20:56–05:41
  • April: 6 h 47 min · 21:46–04:33
  • May: 4 h 39 min · 22:47–03:26
  • June: 3 h 5 min · 23:39–02:43
  • July: 3 h 55 min · 23:19–03:14
  • August: 6 h 3 min · 22:13–04:16
  • September: 8 h 7 min · 21:02–05:09
  • October: 9 h 47 min · 20:03–05:49
  • November: 11 h 5 min · 18:23–05:28
  • December: 11 h 41 min · 18:15–05:56

How to see it

  • Look toward the pole: North in the northern hemisphere, south in the southern – away from city lights.
  • Use your phone's night mode: A camera shows colours the eye cannot see yet – the aurora often looks grey at first.
  • Be patient: The aurora comes in bursts, often 20–30 minutes apart.
  • Check the clouds: Without a clear view to the horizon nothing helps.

FAQ

  • What does the Kp index mean? The Kp index measures from 0 to 9 how disturbed Earth's magnetic field is. The higher it is, the farther the auroral oval moves toward the equator. From Kp 5 NOAA speaks of a geomagnetic storm.
  • When is the best time for the northern lights? Around magnetic midnight – in central Europe roughly between 10 pm and 2 am – and around the equinoxes in spring and autumn, when storms are a little more frequent.
  • How reliable is the forecast? The Kp forecast for the next hours is quite good, for two or three days only rough: solar storms take one to three days to reach Earth, and their exact strength often only shows shortly before.