Northern lights in Ketchikan, Alaska
The southernmost on this list, Ketchikan's daylight is the mildest in Alaska: about 17.25 summer hours, 7.25 in winter.
Ketchikan
…Checking tonight's sky…
The next three nights
Geomagnetic activity (Kp) forecast for the selected town's dark hours. Kp runs 0–9; how much a town needs depends on its magnetic latitude. New to this? What the Kp index means, in plain words → Nights tagged “outlook” use NOAA’s 27-day outlook where the 3-day forecast doesn’t reach — whole-day values, so treat them as rougher estimates.
What Ketchikan needs for a show
Whether aurora reaches a town is mostly a matter of magnetic latitude — distance from the magnetic pole, not the geographic one. Ketchikan sits at magnetic latitude 59.2°, which puts it in the Kp 4 band: when the forecast Kp for the dark hours reaches about 4, the oval's southern edge reaches Ketchikan and displays can appear low on the northern horizon. At Kp 6 or better, expect the band overhead at times. The same law draws the band on the homepage globe: the oval's edge at magnetic latitude 69 − 3×Kp.
| Magnetic latitude | 59.2° |
|---|---|
| Kp needed (horizon show) | About 4 |
| Kp for a strong overhead show | About 6+ |
| Coordinates | 55.3422°N, 131.6461°W · Southeast |
Kp is only one of four ingredients in the live call above: cloud cover over the dark hours, the town's actual darkness window, and moonlight all count too. A Kp 6 night under solid cloud is still a no — which is why the verdict, not the index, leads this page.
Ketchikan’s aurora season
Ketchikan has a real off-season: from about May 7 to Aug 5 (91 nights) the sun never dips 18° below the horizon, so it never gets truly dark and aurora can't be seen even when it's active. Outside that stretch, 274 nights in 2027 get a true-dark window.
| Month (2027) | True darkness | Typical dark window, mid-month |
|---|---|---|
| January | Every night | 11 hr 47 min |
| February | Every night | 10 hr 10 min |
| March | Every night | 8 hr 1 min |
| April | Every night | 4 hr 48 min |
| May | 6 of 31 nights | — |
| June | No true darkness | — |
| July | No true darkness | — |
| August | 26 of 31 nights | 3 hr 10 min |
| September | Every night | 6 hr 58 min |
| October | Every night | 9 hr 28 min |
| November | Every night | 11 hr 21 min |
| December | Every night | 12 hr 15 min |
True darkness = the sun below −18° (end of astronomical twilight), computed with the standard NOAA solar algorithm for Ketchikan’s coordinates. The live call at the top of this page uses tonight's actual window, not these averages.
Ketchikan in daylight
Sunrise, sunset, and daylight hours for Ketchikan — today or any date — are on our sister site: Ketchikan at Alaska Daylight →
On the water nearby
Night fishing or camping out of Ketchikan? The nearest tide station is Ketchikan (1 mi SE) — tide predictions and minus tides at Alaska Tide Charts.