Can you see the northern lights in Saint-Jérôme in July?

On dark, clear nights with enough activity. 31 of 31 nights at Saint-Jérôme have civil darkness, and 3% of past July days reached Kp 6.

How dark is Saint-Jérôme in July?

Saint-Jérôme averages 7.4 hours of civil night a night in July 2027, from 6 h 57 min on the 1st to 7 h 57 min on the last night.

How cloudy is Saint-Jérôme in July?

NASA POWER's 2001 to 2020 climatology gives Saint-Jérôme's 1 degree cell 56% mean cloud in July, against 64% for the whole year. It is an all-hours average, not a forecast.

What is the best night in July 2027 for aurora in Saint-Jérôme?

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

Is July or August better in Saint-Jérôme?

By civil night times the clear share, July scores 3.2 hours at Saint-Jérôme and August 3.8. August comes out ahead.

Saint-Jérôme · July 2027

Northern lights in Saint-Jérôme in July 2027

Answer

July gives Saint-Jérôme 7.3 hours of civil night on the 15th, the 11th darkest of its 12 months, under 56% mean cloud. 3% of July days since 1996 reached Kp 6, enough for the oval edge to reach Saint-Jérôme.

7.4 h

civil night, average night

SunCalc for 45.78, -74.00; NASA POWER; GFZ Kp

July against the rest of the year

4.1

4.0

3.3

2.8

2.7

3.2

3.8

4.8

3.8

3.4

July cloud at Saint-Jérôme averages 56% in NASA POWER's 2001 to 2020 record, 8 points clearer than its yearly mean. September is Saint-Jérôme's clearest month at 54%. By civil night times clear sky, July scores 3.2 hours at Saint-Jérôme, 10th of 12. Trois-Rivières, 129 km away, averages 60%, cloudier by 4 points.

Civil night at Saint-Jérôme starts July at 6 h 57 min and reaches 7 h 57 min by July 31 as the nights lengthen by 1.0 hours. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 3.6 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/Toronto dates. Saint-Jérôme gets 109 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
6% lit
5.5 h
2
1% lit
6.7 h
3
0% lit
7.0 h
New
4
2% lit
7.0 h
5
6% lit
6.4 h
6
13% lit
6.0 h
7
22% lit
5.6 h
8
33% lit
5.3 h
9
43% lit
5.0 h
10
54% lit
4.6 h
11
65% lit
4.3 h
12
74% lit
3.8 h
13
82% lit
3.2 h
14
89% lit
2.5 h
15
94% lit
1.7 h
16
98% lit
0.7 h
17
100% lit
0.0 h
18
100% lit
0.0 h
Full
19
98% lit
0.0 h
20
94% lit
0.4 h
21
89% lit
0.7 h
22
83% lit
1.0 h
23
75% lit
1.3 h
24
66% lit
1.6 h
25
56% lit
2.0 h
26
45% lit
2.4 h
27
35% lit
3.0 h
28
24% lit
3.7 h
29
15% lit
4.7 h
30
8% lit
5.9 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

Saint-Jérôme needs Kp 6 for the average oval edge to sit overhead. 26 of the 930 July days from 1996 to 2025 (3%) reached it in the GFZ Potsdam record, 9th of 12 months; storm days with Kp 5 or more made up 9%. Saint-Jérôme sits at 55.0 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 6.

July across Canada

No month-page town in Canada has more civil night on July 15 than Saint-Jérôme; the national median is 6.5 hours. Coming from June (6.9 hours at Saint-Jérôme), July adds darkness, and the nights keep growing into August (8.7 hours on the 15th).

Civil night on July 15 and July cloud, month-page towns in Canada
Town	Civil night	Cloud
Saint-Jérôme	7.3 h	56%
Sydney	7.3 h	66%
Québec	7.2 h	62%
Greater Sudbury	7.2 h	54%
Trois-Rivières	7.2 h	60%
St. John's	7.0 h	73%
Saguenay	6.9 h	70%
Thunder Bay	6.9 h	65%
Winnipeg	6.6 h	50%
Kelowna	6.6 h	44%
Lethbridge	6.6 h	42%
Regina	6.5 h	49%

Darkness and moon, every night

Saint-Jérôme, July 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
Thu Jul 1	6 h 57 min	2 h 51 min	5 h 33 min	4 h	6%
Fri Jul 2	6 h 58 min	2 h 53 min	6 h 39 min	4 h	1%
Sat Jul 3	7 h	2 h 56 min	7 h	4 h	0%
Sun Jul 4	7 h 1 min	2 h 58 min	6 h 57 min	4 h	2%
Mon Jul 5	7 h 2 min	3 h 1 min	6 h 24 min	3 h 52 min	6%
Tue Jul 6	7 h 3 min	3 h 4 min	5 h 58 min	3 h 25 min	13%
Wed Jul 7	7 h 5 min	3 h 7 min	5 h 36 min	3 h 3 min	22%
Thu Jul 8	7 h 6 min	3 h 11 min	5 h 17 min	2 h 42 min	33%
Fri Jul 9	7 h 8 min	3 h 14 min	4 h 58 min	2 h 22 min	43%
Sat Jul 10	7 h 9 min	3 h 17 min	4 h 37 min	2 h 1 min	54%
Sun Jul 11	7 h 11 min	3 h 21 min	4 h 15 min	1 h 37 min	65%
Mon Jul 12	7 h 13 min	3 h 25 min	3 h 47 min	1 h 9 min	74%
Tue Jul 13	7 h 15 min	3 h 28 min	3 h 14 min	34 min	82%
Wed Jul 14	7 h 16 min	3 h 32 min	2 h 32 min	0 min	89%
Thu Jul 15	7 h 18 min	3 h 36 min	1 h 41 min	0 min	94%
Fri Jul 16	7 h 20 min	3 h 40 min	43 min	0 min	98%
Sat Jul 17	7 h 22 min	3 h 44 min	0 min	0 min	100%
Sun Jul 18	7 h 25 min	3 h 48 min	0 min	0 min	100%
Mon Jul 19	7 h 27 min	3 h 52 min	1 min	0 min	98%
Tue Jul 20	7 h 29 min	3 h 57 min	23 min	0 min	94%
Wed Jul 21	7 h 31 min	4 h 1 min	42 min	0 min	89%
Thu Jul 22	7 h 34 min	4 h 5 min	59 min	15 min	83%
Fri Jul 23	7 h 36 min	4 h 9 min	1 h 17 min	32 min	75%
Sat Jul 24	7 h 39 min	4 h 14 min	1 h 36 min	50 min	66%
Sun Jul 25	7 h 41 min	4 h 18 min	1 h 58 min	1 h 10 min	56%
Mon Jul 26	7 h 44 min	4 h 22 min	2 h 24 min	1 h 35 min	45%
Tue Jul 27	7 h 46 min	4 h 27 min	2 h 58 min	2 h 8 min	35%
Wed Jul 28	7 h 49 min	4 h 31 min	3 h 42 min	2 h 50 min	24%
Thu Jul 29	7 h 52 min	4 h 36 min	4 h 40 min	3 h 47 min	15%
Fri Jul 30	7 h 54 min	4 h 40 min	5 h 53 min	4 h	8%
Sat Jul 31	7 h 57 min	4 h 45 min	7 h 17 min	4 h	2%

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

Questions

Can you see the northern lights in Saint-Jérôme in July?: On dark, clear nights with enough activity. 31 of 31 nights at Saint-Jérôme have civil darkness, and 3% of past July days reached Kp 6.
How dark is Saint-Jérôme in July?: Saint-Jérôme averages 7.4 hours of civil night a night in July 2027, from 6 h 57 min on the 1st to 7 h 57 min on the last night.
How cloudy is Saint-Jérôme in July?: NASA POWER's 2001 to 2020 climatology gives Saint-Jérôme's 1 degree cell 56% mean cloud in July, against 64% for the whole year. It is an all-hours average, not a forecast.
What is the best night in July 2027 for aurora in Saint-Jérôme?: By darkness and moon alone, Jul 1, with 4 h of moon-free darkness inside 10 PM to 2 AM at Saint-Jérôme. Activity on that date will only be known hours ahead.
Is July or August better in Saint-Jérôme?: By civil night times the clear share, July scores 3.2 hours at Saint-Jérôme and August 3.8. 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.