Washington, United States
Northern lights in Seattle
Answer
Tonight
Darkness window open
Civil darkness has begun.
Observed 10:53 UTC, forecast 12:26 UTC, 93 min lead
Clock times in America/Los_Angeles
Valid 11:00 to 12:00 UTC
Storm level needed
Seattle sits at 47.61N 122.33W in Washington, United States. The IGRF-14 centered dipole puts Seattle at 53.0 degrees geomagnetic latitude, 5.4 degrees closer to the magnetic pole than its map latitude suggests. Seattle sits at 53.0 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G3 (Kp = 7). By SWPC's rule the average oval edge is overhead only at Kp 7.
"aurora has been seen as low as Illinois and Oregon (typically 50° geomagnetic lat.)"
The nearest other Glow towns are Redmond (17 km), Shoreline (17 km), Kent (26 km). Redmond sits 0.1 degrees higher on the dipole and needs the same Kp.
Approximate: SWPC calls its Kp to latitude rule an average, and a centered dipole can differ by a degree from fuller field models. How the storm level is matched
The year in darkness
Every night of 2026 at Seattle has some civil darkness; the shortest month sample still has 6.5 hours. Every evening of the year at Seattle clears Glow's dark-season bar of 4 hours of civil night between 18:00 and 06:00. Seattle's longest night of the year, Dec 17, has 14 h 16 min of civil night.
Solar midnight at Seattle, when the sun is lowest, falls at 00:05 on local clocks on December 15 and 01:10 on June 15. That is 5 min after midnight in December and 1 h 10 min after midnight in June, the gap set by daylight saving and the equation of time. So at Seattle the darkest hour sits near the middle of SWPC's 10 PM to 2 AM window in winter.
Month by month
| Month | Night | Civil | Cloud | Clear dark | |
|---|---|---|---|---|---|
| Jan | 13.8 h | 11.3 h | 80% | 2.8 h | |
| Feb | 12.5 h | 10.1 h | 74% | 3.3 h | |
| Mar | 11.0 h | 8.5 h | 79% | 2.3 h | |
| Apr | 9.1 h | 6.3 h | 75% | 2.3 h | |
| May | 7.5 h | 3.8 h | 70% | 2.3 h | |
| Jun | 6.5 h | 1.3 h | 68% | 2.1 h | |
| Jul | 7.0 h | 2.8 h | 47% | 3.7 h | |
| Aug | 8.5 h | 5.5 h | 48% | 4.4 h | |
| Sep | 10.3 h | 7.8 h | 53% | 4.8 hbest | |
| Oct | 12.0 h | 9.6 h | 68% | 3.8 h | |
| Nov | 13.5 h | 11.1 h | 77% | 3.1 h | |
| Dec | 14.3 h | 11.7 h | 79% | 3.0 h |
By the 15th-of-the-month sample, December is the darkest month at Seattle with 14.3 hours of civil night and June the lightest at 6.5. Across the year Seattle gets 3,834 hours of civil night. Astronomical night at Seattle, the sun 18 degrees or more below the horizon, lasts 11.7 hours on December 15.
NASA POWER's 2001 to 2020 all-hours climatology puts mean cloud amount for the 1 degree cell around Seattle at 68% across the year, from 47% in July to 80% in January. In the months with at least 4 hours of civil night Seattle averages 68%, against a median of 61% for Glow towns in United States.
Multiplying civil night by the clear share of the sky gives September the best score, 4.8 hours, ahead of August at 4.4. Seattle's equinox months score 2.3 in March and 4.8 in September, the weeks SWPC links with larger storms.
Kp history
From 1996 to 2025, the GFZ Potsdam record shows a 3-hour Kp of 7 or more, the level that puts the average oval edge over Seattle, on 1% of days. At Seattle's level the share runs from 0% in February to 2% in October, while storm days with Kp 5 or more made up 10%.
Share of UTC days in each calendar month whose highest 3-hour Kp reached Kp 7. Kp history by year
Moon, next 30 nights
Over the 30 nights from Oct 1, the new moon falls on Oct 10 and the full moon on Oct 25, in America/Los_Angeles dates. 15 of the 30 nights at Seattle have at least 2 moon-free dark hours inside 10 PM to 2 AM, and Oct 5 has the most at 4 h. Tonight Seattle has 11 h 15 min of civil night, 2 h 5 min of it with the moon down.
- 1
64% lit
2.1 h
- 2
53% lit
3.2 h
- 3
42% lit
4.5 h
- 4
31% lit
5.9 h
- 5
21% lit
7.3 h
- 6
13% lit
8.7 h
- 7
6% lit
9.9 h
- 8
2% lit
11.2 h
- 9
0% lit
11.7 h
- 10
1% lit
11.8 h
- 11
3% lit
11.8 h
- 12
7% lit
11.8 h
- 13
13% lit
11.6 h
- 14
20% lit
10.9 h
- 15
28% lit
10.2 h
- 16
37% lit
9.3 h
- 17
46% lit
8.2 h
- 18
56% lit
7.1 h
- 19
65% lit
6.0 h
- 20
74% lit
4.8 h
- 21
83% lit
3.6 h
- 22
90% lit
2.4 h
- 23
95% lit
1.2 h
- 24
99% lit
0.0 h
- 25
100% lit
0.0 h
- 26
98% lit
0.0 h
- 27
94% lit
0.0 h
- 28
87% lit
0.8 h
- 29
78% lit
1.9 h
- 30
68% lit
3.1 h
Each cell is the night that starts on that date. Hours are civil-dark time with the moon below the horizon; the green rule scales with them. Green outline: new moon. Bone outline: full moon.
Within United States
Among the 13 Glow towns in Washington, Seattle ranks 7th by dipole latitude against a regional median of 53.0 degrees; Bellingham sits highest at 54.1. Among the 136 Glow towns in United States, Seattle ranks 32nd by dipole latitude against a national median of 51.5 degrees; Fairbanks sits highest at 65.7. On December 15 Seattle gets 14.3 hours of civil night, 6th longest of 136 in United States, where the median is 13.8.
Questions
- Can you see the northern lights in Seattle?
- Seattle sits at 53.0 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G3 (Kp = 7). By SWPC's rule the average oval edge is overhead only at Kp 7. Clear, dark sky over Seattle still decides it.
- When is it dark enough in Seattle?
- Every night at Seattle has civil darkness. Tonight has 11 h 15 min, and December 15 has 14.3 hours.
- What is the best month for aurora in Seattle?
- September, by civil night at Seattle times the clear share of the sky from NASA POWER's 2001 to 2020 average.
- How cloudy is Seattle in the dark months?
- About 68% mean cloud amount over Seattle in the months with at least 4 hours of civil night, from NASA POWER's 2001 to 2020 all-hours climatology.
- How often is activity high enough for Seattle?
- A 3-hour Kp of 7 or more, the level that puts the average oval edge overhead, occurred on 1% of days from 1996 to 2025 in the GFZ Potsdam record.
- Why not just show Kp for Seattle?
- Kp is a planetary index. Seattle's question is local: its OVATION cell, whether it is dark, and how cloudy NWS says the grid square is.
- Is Seattle cloud cover from NWS?
- Yes. Seattle is in the US, so skyCover comes from api.weather.gov for the grid square that holds the city.
Nearby and related
Nearest Glow towns
Seattle by month
Region and comparisons