Can you see the northern lights in Marysville in May?

On dark, clear nights with enough activity. 31 of 31 nights at Marysville have civil darkness, and 1% of past May days reached Kp 7.

How dark is Marysville in May?

Marysville averages 7.4 hours of civil night a night in May 2027, from 8 h 10 min on the 1st to 6 h 46 min on the last night.

How cloudy is Marysville in May?

NASA POWER's 2001 to 2020 climatology gives Marysville's 1 degree cell 67% mean cloud in May, against 68% for the whole year. It is an all-hours average, not a forecast.

What is the best night in May 2027 for aurora in Marysville?

By darkness and moon alone, May 1, with 4 h of moon-free darkness inside 10 PM to 2 AM at Marysville. Activity on that date will only be known hours ahead.

Is May or June better in Marysville?

By civil night times the clear share, May scores 2.4 hours at Marysville and June 2.3. May comes out ahead.

Marysville · May 2027

Northern lights in Marysville in May 2027

Answer

May gives Marysville 7.4 hours of civil night on the 15th, the 10th darkest of its 12 months, under 67% mean cloud. 1% of May days since 1996 reached Kp 7, enough for the oval edge to reach Marysville.

7.4 h

civil night, average night

SunCalc for 48.05, -122.18; NASA POWER; GFZ Kp

May against the rest of the year

2.4

3.0

2.3

2.5

2.4

2.3

3.9

4.6

4.7

3.6

2.8

2.4

May cloud at Marysville averages 67% in NASA POWER's 2001 to 2020 record, close to its yearly mean of 68%. July is Marysville's clearest month at 44%. By civil night times clear sky, May scores 2.4 hours at Marysville, 8th of 12. Seattle, 51 km away, averages 70%, cloudier by 3 points.

Civil night at Marysville starts May at 8 h 10 min and reaches 6 h 46 min by May 31, 1.4 hours shorter. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 3.6 hours on the 15th.

May night by night

May opens toward a new moon on May 6, with full moon on May 20, in America/Los_Angeles dates. Marysville gets 117 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: May 1 (4 h), May 2 (4 h), May 3 (4 h).

1
19% lit
7.0 h
2
12% lit
7.2 h
3
6% lit
7.5 h
4
2% lit
7.8 h
5
0% lit
8.0 h
6
1% lit
7.5 h
New
7
5% lit
6.1 h
8
11% lit
5.0 h
9
19% lit
4.0 h
10
29% lit
3.4 h
11
40% lit
2.8 h
12
51% lit
2.4 h
13
62% lit
2.1 h
14
73% lit
1.8 h
15
82% lit
1.4 h
16
89% lit
1.1 h
17
95% lit
0.8 h
18
98% lit
0.3 h
19
100% lit
0.0 h
20
99% lit
0.4 h
Full
21
97% lit
1.4 h
22
92% lit
2.2 h
23
86% lit
2.8 h
24
79% lit
3.3 h
25
71% lit
3.6 h
26
62% lit
3.9 h
27
53% lit
4.2 h
28
43% lit
4.4 h
29
34% lit
4.6 h
30
24% lit
4.9 h
31
16% lit
5.2 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 Mays

Marysville needs Kp 7 for the average oval edge to sit overhead. 13 of the 930 May days from 1996 to 2025 (1%) reached it in the GFZ Potsdam record, 5th of 12 months; storm days with Kp 5 or more made up 10%. Marysville sits at 53.5 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.

May across United States

Marysville ranks 7th in United States for civil night on May 15, behind Buffalo at 8.1 hours. Coming from April (9.1 hours at Marysville), May loses darkness, and June brings shorter nights (6.5 hours on the 15th).

Civil night on May 15 and May cloud, month-page towns in United States
Town	Civil night	Cloud
Buffalo	8.1 h	65%
Portland, Maine	8.0 h	66%
Minneapolis	7.9 h	63%
Duluth	7.6 h	65%
Fargo	7.6 h	61%
Seattle	7.5 h	70%
Marysville	7.4 h	67%
Juneau	5.1 h	74%
Anchorage	3.8 h	79%
Eagle River	3.7 h	79%
Fairbanks	0.0 h	70%

Darkness and moon, every night

Marysville, May 2027: each night from local noon to the next noon
Night	Civil	Astronomical	Moon-free dark	Moon-free, 10 PM to 2 AM	Moon lit
Sat May 1	8 h 10 min	4 h 57 min	6 h 59 min	4 h	19%
Sun May 2	8 h 7 min	4 h 52 min	7 h 13 min	4 h	12%
Mon May 3	8 h 3 min	4 h 46 min	7 h 29 min	4 h	6%
Tue May 4	8 h	4 h 41 min	7 h 49 min	4 h	2%
Wed May 5	7 h 57 min	4 h 36 min	7 h 57 min	4 h	0%
Thu May 6	7 h 54 min	4 h 30 min	7 h 27 min	4 h	1%
Fri May 7	7 h 50 min	4 h 25 min	6 h 7 min	3 h 7 min	5%
Sat May 8	7 h 47 min	4 h 19 min	4 h 58 min	2 h	11%
Sun May 9	7 h 44 min	4 h 14 min	4 h 3 min	1 h 6 min	19%
Mon May 10	7 h 41 min	4 h 8 min	3 h 22 min	27 min	29%
Tue May 11	7 h 38 min	4 h 3 min	2 h 50 min	0 min	40%
Wed May 12	7 h 35 min	3 h 57 min	2 h 26 min	0 min	51%
Thu May 13	7 h 32 min	3 h 52 min	2 h 5 min	0 min	62%
Fri May 14	7 h 29 min	3 h 46 min	1 h 46 min	0 min	73%
Sat May 15	7 h 26 min	3 h 40 min	1 h 27 min	0 min	82%
Sun May 16	7 h 23 min	3 h 35 min	1 h 8 min	0 min	89%
Mon May 17	7 h 20 min	3 h 29 min	46 min	0 min	95%
Tue May 18	7 h 17 min	3 h 23 min	20 min	0 min	98%
Wed May 19	7 h 14 min	3 h 17 min	0 min	0 min	100%
Thu May 20	7 h 12 min	3 h 12 min	26 min	0 min	99%
Fri May 21	7 h 9 min	3 h 6 min	1 h 24 min	55 min	97%
Sat May 22	7 h 6 min	3 h	2 h 11 min	1 h 43 min	92%
Sun May 23	7 h 4 min	2 h 54 min	2 h 47 min	2 h 21 min	86%
Mon May 24	7 h 1 min	2 h 48 min	3 h 15 min	2 h 50 min	79%
Tue May 25	6 h 59 min	2 h 42 min	3 h 37 min	3 h 13 min	71%
Wed May 26	6 h 57 min	2 h 36 min	3 h 54 min	3 h 32 min	62%
Thu May 27	6 h 54 min	2 h 30 min	4 h 10 min	3 h 48 min	53%
Fri May 28	6 h 52 min	2 h 24 min	4 h 24 min	4 h	43%
Sat May 29	6 h 50 min	2 h 19 min	4 h 38 min	4 h	34%
Sun May 30	6 h 48 min	2 h 13 min	4 h 53 min	4 h	24%
Mon May 31	6 h 46 min	2 h 7 min	5 h 11 min	4 h	16%

Moon lit: SunCalc illuminated fraction at the middle of the 10 PM to 2 AM window.

Questions

Can you see the northern lights in Marysville in May?: On dark, clear nights with enough activity. 31 of 31 nights at Marysville have civil darkness, and 1% of past May days reached Kp 7.
How dark is Marysville in May?: Marysville averages 7.4 hours of civil night a night in May 2027, from 8 h 10 min on the 1st to 6 h 46 min on the last night.
How cloudy is Marysville in May?: NASA POWER's 2001 to 2020 climatology gives Marysville's 1 degree cell 67% mean cloud in May, against 68% for the whole year. It is an all-hours average, not a forecast.
What is the best night in May 2027 for aurora in Marysville?: By darkness and moon alone, May 1, with 4 h of moon-free darkness inside 10 PM to 2 AM at Marysville. Activity on that date will only be known hours ahead.
Is May or June better in Marysville?: By civil night times the clear share, May scores 2.4 hours at Marysville and June 2.3. May 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.