Federal Way · July 2027
Northern lights in Federal Way in July 2027
Answer
July against the rest of the year
July cloud at Federal Way averages 47% in NASA POWER's 2001 to 2020 record, 21 points clearer than its yearly mean. No month at Federal Way is clearer. By civil night times clear sky, July scores 3.8 hours at Federal Way, 4th of 12. Seattle, 32 km away, averages the same 47%.
Civil night at Federal Way starts July at 6 h 40 min and reaches 7 h 45 min by July 31 as the nights lengthen by 1.1 hours. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 3.0 hours on the 15th.
July night by night
July opens toward a new moon on Jul 3, with full moon on Jul 18, in America/Los_Angeles dates. Federal Way gets 105 hours of civil night with the moon below the horizon across the month. The best of them for moon-free darkness inside 10 PM to 2 AM: Jul 1 (4 h), Jul 2 (4 h), Jul 3 (4 h).
- 1
5% lit
5.4 h
- 2
1% lit
6.5 h
- 3
0% lit
6.7 h
- 4
2% lit
6.6 h
- 5
7% lit
6.1 h
- 6
14% lit
5.7 h
- 7
24% lit
5.4 h
- 8
34% lit
5.1 h
- 9
45% lit
4.8 h
- 10
56% lit
4.5 h
- 11
66% lit
4.1 h
- 12
75% lit
3.7 h
- 13
83% lit
3.1 h
- 14
90% lit
2.4 h
- 15
95% lit
1.6 h
- 16
98% lit
0.6 h
- 17
100% lit
0.0 h
- 18
100% lit
0.0 h
- 19
98% lit
0.0 h
- 20
94% lit
0.3 h
- 21
89% lit
0.6 h
- 22
82% lit
0.9 h
- 23
74% lit
1.2 h
- 24
64% lit
1.5 h
- 25
54% lit
1.9 h
- 26
44% lit
2.3 h
- 27
33% lit
2.8 h
- 28
23% lit
3.6 h
- 29
14% lit
4.6 h
- 30
7% lit
5.8 h
- 31
2% lit
7.3 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.
Activity in past Julys
Federal Way needs Kp 7 for the average oval edge to sit overhead. 10 of the 930 July days from 1996 to 2025 (1%) reached it in the GFZ Potsdam record, 8th of 12 months; storm days with Kp 5 or more made up 9%. Federal Way sits at 52.8 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.
July across United States
Federal Way ranks 5th in United States for civil night on July 15, behind Buffalo at 7.8 hours. Coming from June (6.6 hours at Federal Way), July adds darkness, and the nights keep growing into August (8.6 hours on the 15th).
| Town | Civil night | Cloud |
|---|---|---|
| Buffalo | 7.8 h | 56% |
| Portland, Maine | 7.6 h | 55% |
| Minneapolis | 7.4 h | 46% |
| Duluth | 7.2 h | 51% |
| Federal Way | 7.1 h | 47% |
| Fargo | 7.1 h | 48% |
| Seattle | 7.0 h | 47% |
| Juneau | 4.1 h | 81% |
| Anchorage | 2.1 h | 83% |
| Eagle River | 2.0 h | 83% |
| Fairbanks | 0.0 h | 77% |
Darkness and moon, every night
| Night | Civil | Astronomical | Moon-free dark | Moon-free, 10 PM to 2 AM | Moon lit |
|---|---|---|---|---|---|
| Thu Jul 1 | 6 h 40 min | 1 h 53 min | 5 h 25 min | 4 h | 5% |
| Fri Jul 2 | 6 h 41 min | 1 h 57 min | 6 h 33 min | 4 h | 1% |
| Sat Jul 3 | 6 h 43 min | 2 h 1 min | 6 h 43 min | 4 h | 0% |
| Sun Jul 4 | 6 h 44 min | 2 h 5 min | 6 h 37 min | 4 h | 2% |
| Mon Jul 5 | 6 h 45 min | 2 h 9 min | 6 h 7 min | 3 h 31 min | 7% |
| Tue Jul 6 | 6 h 47 min | 2 h 14 min | 5 h 44 min | 3 h 6 min | 14% |
| Wed Jul 7 | 6 h 48 min | 2 h 18 min | 5 h 24 min | 2 h 46 min | 24% |
| Thu Jul 8 | 6 h 50 min | 2 h 23 min | 5 h 7 min | 2 h 27 min | 34% |
| Fri Jul 9 | 6 h 51 min | 2 h 27 min | 4 h 49 min | 2 h 8 min | 45% |
| Sat Jul 10 | 6 h 53 min | 2 h 32 min | 4 h 30 min | 1 h 49 min | 56% |
| Sun Jul 11 | 6 h 55 min | 2 h 37 min | 4 h 8 min | 1 h 26 min | 66% |
| Mon Jul 12 | 6 h 57 min | 2 h 42 min | 3 h 42 min | 58 min | 75% |
| Tue Jul 13 | 6 h 59 min | 2 h 47 min | 3 h 8 min | 24 min | 83% |
| Wed Jul 14 | 7 h 1 min | 2 h 52 min | 2 h 26 min | 0 min | 90% |
| Thu Jul 15 | 7 h 3 min | 2 h 57 min | 1 h 35 min | 0 min | 95% |
| Fri Jul 16 | 7 h 5 min | 3 h 2 min | 35 min | 0 min | 98% |
| Sat Jul 17 | 7 h 8 min | 3 h 7 min | 0 min | 0 min | 100% |
| Sun Jul 18 | 7 h 10 min | 3 h 12 min | 0 min | 0 min | 100% |
| Mon Jul 19 | 7 h 12 min | 3 h 17 min | 1 min | 0 min | 98% |
| Tue Jul 20 | 7 h 15 min | 3 h 22 min | 21 min | 0 min | 94% |
| Wed Jul 21 | 7 h 17 min | 3 h 27 min | 38 min | 16 min | 89% |
| Thu Jul 22 | 7 h 20 min | 3 h 32 min | 55 min | 31 min | 82% |
| Fri Jul 23 | 7 h 22 min | 3 h 37 min | 1 h 12 min | 47 min | 74% |
| Sat Jul 24 | 7 h 25 min | 3 h 43 min | 1 h 30 min | 1 h 3 min | 64% |
| Sun Jul 25 | 7 h 28 min | 3 h 48 min | 1 h 51 min | 1 h 23 min | 54% |
| Mon Jul 26 | 7 h 30 min | 3 h 53 min | 2 h 16 min | 1 h 47 min | 44% |
| Tue Jul 27 | 7 h 33 min | 3 h 58 min | 2 h 50 min | 2 h 19 min | 33% |
| Wed Jul 28 | 7 h 36 min | 4 h 3 min | 3 h 35 min | 3 h 3 min | 23% |
| Thu Jul 29 | 7 h 39 min | 4 h 8 min | 4 h 34 min | 4 h | 14% |
| Fri Jul 30 | 7 h 42 min | 4 h 14 min | 5 h 50 min | 4 h | 7% |
| Sat Jul 31 | 7 h 45 min | 4 h 19 min | 7 h 16 min | 4 h | 2% |
Questions
- Can you see the northern lights in Federal Way in July?
- On dark, clear nights with enough activity. 31 of 31 nights at Federal Way have civil darkness, and 1% of past July days reached Kp 7.
- How dark is Federal Way in July?
- Federal Way averages 7.1 hours of civil night a night in July 2027, from 6 h 40 min on the 1st to 7 h 45 min on the last night.
- How cloudy is Federal Way in July?
- NASA POWER's 2001 to 2020 climatology gives Federal Way's 1 degree cell 47% mean cloud in July, against 68% for the whole year. It is an all-hours average, not a forecast.
- What is the best night in July 2027 for aurora in Federal Way?
- By darkness and moon alone, Jul 1, with 4 h of moon-free darkness inside 10 PM to 2 AM at Federal Way. Activity on that date will only be known hours ahead.
- Is July or August better in Federal Way?
- By civil night times the clear share, July scores 3.8 hours at Federal Way and August 4.5. August comes out ahead.
Sources and verification
- SunCalchttps://github.com/mourner/suncalc
- NASA POWER climatologyhttps://power.larc.nasa.gov/docs/services/api/temporal/climatology/
- GFZ Potsdam Kp indexhttps://kp.gfz.de/en/data
- NOAA SWPC, Tips on viewing the aurorahttps://www.spaceweather.gov/content/tips-viewing-aurora
Quoted figures last checked against their sources on 2026-09-30; next review 2026-12-31. Computed figures come from SunCalc and the IGRF-14 dipole as described in the methodology. Every quote is listed in the sources ledger.