Rock Forest weather in September

In September, Rock Forest sees average daytime highs of 19°C and overnight lows near 9°C, with 102 mm of rain across 11.6 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 21°C in the first days to 16°C by the end. The sky is clear or mostly clear about 27% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Rock Forest's 1st-clearest and 9th-windiest month. For the whole year in context, see Rock Forest's year-round climate.

Daytime high: 19°; 4th warmest
Overnight low: 9°; 9th coldest
Rainfall: 102 mm; 11.6 wet days
Daylight: 12 h 18 min; 5:33 AM – 5:52 PM
Cloud cover: 60%; 1st clearest
Wind: 11 km/h; 9th windiest
Solar energy: 3.83 kWh/m²
Travel score: 5.7; out of 10

← August Rock Forest year-round climate October →Best places to visit in September

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 21°C in the first days to 16°C by the end.

A typical September day in Rock Forest reaches about 19°C in the afternoon and slips back to 9°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 13°C and 25°C. Set against its neighbours, September runs about 4°C cooler than August and about 7°C warmer than October.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	22	21	21	21	21	21	21	20	20	20	20	20	20	19	19	19	19	19	18	18	18	18	18	17	17	17	17	16	16	16
Avg low (°C)	12	12	12	11	11	11	11	11	10	10	10	10	10	10	9	9	9	9	9	8	8	8	8	8	8	7	7	7	7	7

	Avg high (°C)	Avg low (°C)
1	22	12
2	21	12
3	21	12
4	21	11
5	21	11
6	21	11
7	21	11
8	20	11
9	20	10
10	20	10
11	20	10
12	20	10
13	20	10
14	19	10
15	19	9
16	19	9
17	19	9
18	19	9
19	18	9
20	18	8
21	18	8
22	18	8
23	18	8
24	17	8
25	17	8
26	17	7
27	17	7
28	16	7
29	16	7
30	16	7

How September really feels in Rock Forest

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C

heat index over the day's high

Days feeling ≤ 0°C

wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Rock Forest weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 6th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	-5° / -14°	74	12.2	12.2	8.9	0.0
Feb	-4° / -13°	63	10.3	10.9	10.1	0.0
Mar	2° / -7°	79	12.2	9.2	11.6	0.0
Apr	10° / 0°	96	12.7	4.4	13.2	2.0
May	17° / 7°	113	14.2	0.5	14.6	4.8
Jun	22° / 12°	128	14.1	0	15.4	5.8
Jul	24° / 14°	119	14.7	0	15.1	6.2
Aug	23° / 14°	114	13.7	0	13.9	6.3
Sep	19° / 9°	102	11.6	0	12.3	5.7
Oct	12° / 4°	118	13.2	1.5	10.7	2.9
Nov	5° / -3°	89	12.9	6.9	9.3	0.3
Dec	-2° / -9°	89	13.7	11.8	8.6	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 56%.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	48	48	47	46	47	47	46	46	46	46	46	45	44	45	45	45	44	44	44	44	42	42	42	41	40	40	40	39	38	38
Cloudier (%)	52	52	53	54	53	53	54	54	54	54	54	55	56	55	55	55	56	56	56	56	58	58	58	59	60	60	60	61	62	62

	Clearer (%)	Cloudier (%)
1	48	52
2	48	52
3	47	53
4	46	54
5	47	53
6	47	53
7	46	54
8	46	54
9	46	54
10	46	54
11	46	54
12	45	55
13	44	56
14	45	55
15	45	55
16	45	55
17	44	56
18	44	56
19	44	56
20	44	56
21	42	58
22	42	58
23	42	58
24	41	59
25	40	60
26	40	60
27	40	60
28	39	61
29	38	62
30	38	62

Chance of precipitation in September

Any precipitation

Rock Forest gets around 102 mm of rain over 11.6 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 39% and peaks near 41% on the wettest days.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	40	41	41	41	41	41	41	40	40	40	40	39	39	39	39	38	38	38	38	37	37	37	37	37	38	38	38	39	39	39

	Rain chance (%)
1	40
2	41
3	41
4	41
5	41
6	41
7	41
8	40
9	40
10	40
11	40
12	39
13	39
14	39
15	39
16	38
17	38
18	38
19	38
20	37
21	37
22	37
23	37
24	37
25	38
26	38
27	38
28	39
29	39
30	39

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 69% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Dry (%)	49	51	53	55	55	58	59	59	61	62	63	65	66	67	68	70	72	72	73	75	75	76	78	79	81	82	83	85	86	88
Comfortable (%)	26	26	25	25	25	24	24	24	24	23	23	22	21	21	20	19	18	18	17	16	16	15	14	13	12	12	11	10	9	8
Humid (%)	18	17	16	15	15	14	13	13	12	12	11	11	11	10	10	9	9	9	9	8	8	8	7	7	6	5	5	4	4	3
Muggy (%)	6	6	6	5	5	4	4	4	3	3	3	2	2	2	2	2	1	1	1	1	1	1	1	1	1	1	1	1	1	1

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	49	26	18	6
2	51	26	17	6
3	53	25	16	6
4	55	25	15	5
5	55	25	15	5
6	58	24	14	4
7	59	24	13	4
8	59	24	13	4
9	61	24	12	3
10	62	23	12	3
11	63	23	11	3
12	65	22	11	2
13	66	21	11	2
14	67	21	10	2
15	68	20	10	2
16	70	19	9	2
17	72	18	9	1
18	72	18	9	1
19	73	17	9	1
20	75	16	8	1
21	75	16	8	1
22	76	15	8	1
23	78	14	7	1
24	79	13	7	1
25	81	12	6	1
26	82	12	5	1
27	83	11	5	1
28	85	10	4	1
29	86	9	4	1
30	88	8	3	1

Wind in September

Winds average 11 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	10	10	10	10	10	10	10	10	10	10	10	10	10	11	11	11	11	11	11	11	11	11	11	11	11	11	11	11	11	11
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	10	calm
2	10	calm
3	10	calm
4	10	calm
5	10	calm
6	10	calm
7	10	calm
8	10	calm
9	10	calm
10	10	calm
11	10	calm
12	10	calm
13	10	calm
14	11	calm
15	11	calm
16	11	calm
17	11	calm
18	11	calm
19	11	calm
20	11	calm
21	11	calm
22	11	calm
23	11	calm
24	11	calm
25	11	calm
26	11	calm
27	11	calm
28	11	calm
29	11	calm
30	11	calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 90 minutes over September. Sunrise moves from 5:14 AM to 5:51 AM, and sunset from 6:21 PM to 5:24 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	13.1	13.1	13.0	13.0	12.9	12.9	12.8	12.7	12.7	12.6	12.6	12.5	12.5	12.4	12.4	12.3	12.3	12.2	12.1	12.1	12.0	12.0	11.9	11.9	11.8	11.8	11.7	11.7	11.6	11.6
Sunrise (AM)	5:14	5:15	5:17	5:18	5:19	5:20	5:22	5:23	5:24	5:25	5:27	5:28	5:29	5:30	5:32	5:33	5:34	5:35	5:37	5:38	5:39	5:41	5:42	5:43	5:44	5:46	5:47	5:48	5:49	5:51
Sunset (PM)	6:21	6:19	6:17	6:15	6:14	6:12	6:10	6:08	6:06	6:04	6:02	6:00	5:58	5:56	5:54	5:52	5:50	5:48	5:46	5:44	5:42	5:40	5:38	5:36	5:34	5:32	5:30	5:28	5:26	5:24

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.1	5:14	6:21
2	13.1	5:15	6:19
3	13.0	5:17	6:17
4	13.0	5:18	6:15
5	12.9	5:19	6:14
6	12.9	5:20	6:12
7	12.8	5:22	6:10
8	12.7	5:23	6:08
9	12.7	5:24	6:06
10	12.6	5:25	6:04
11	12.6	5:27	6:02
12	12.5	5:28	6:00
13	12.5	5:29	5:58
14	12.4	5:30	5:56
15	12.4	5:32	5:54
16	12.3	5:33	5:52
17	12.3	5:34	5:50
18	12.2	5:35	5:48
19	12.1	5:37	5:46
20	12.1	5:38	5:44
21	12.0	5:39	5:42
22	12.0	5:41	5:40
23	11.9	5:42	5:38
24	11.9	5:43	5:36
25	11.8	5:44	5:34
26	11.8	5:46	5:32
27	11.7	5:47	5:30
28	11.7	5:48	5:28
29	11.6	5:49	5:26
30	11.6	5:51	5:24

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.83 kWh/m².

For context, solar energy here swings from a low near 1.18 kWh/m² to a high of 5.72 kWh/m² in June across the year — September's 3.83 kWh/m² falls in the middle.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	4.5	4.4	4.4	4.3	4.3	4.3	4.2	4.2	4.1	4.1	4.0	4.0	3.9	3.9	3.8	3.8	3.8	3.7	3.7	3.6	3.6	3.5	3.5	3.4	3.4	3.3	3.3	3.2	3.2	3.1
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate

	Solar energy (kWh/m²)	Level
1	4.5	Bright
2	4.4	Bright
3	4.4	Bright
4	4.3	Bright
5	4.3	Bright
6	4.3	Bright
7	4.2	Bright
8	4.2	Bright
9	4.1	Bright
10	4.1	Bright
11	4.0	Bright
12	4.0	Moderate
13	3.9	Moderate
14	3.9	Moderate
15	3.8	Moderate
16	3.8	Moderate
17	3.8	Moderate
18	3.7	Moderate
19	3.7	Moderate
20	3.6	Moderate
21	3.6	Moderate
22	3.5	Moderate
23	3.5	Moderate
24	3.4	Moderate
25	3.4	Moderate
26	3.3	Moderate
27	3.3	Moderate
28	3.2	Moderate
29	3.2	Moderate
30	3.1	Moderate

Planning a trip in September

Is September a good time to visit Rock Forest?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.7

Sightseeing

4th-best month of the year

2.5

Beach & pool

4th-best month of the year

September is a reasonable time to visit Rock Forest for sightseeing.

What to pack for Rock Forest in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Rock Forest sees daytime highs around 19°C and nights near 9°C. Worth packing: rain gear. About 12 days see rain.

rain gear

UV index in Rock Forest in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Rock Forest peaks around July 13 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	1	2	4	5	6	6	8	3	5	3	2	1
Level	Low	Low	Moderate	Moderate	High	High	Very high	Moderate	High	Moderate	Low	Low

	UV index (midday)	Level
Jan	1	Low
Feb	2	Low
Mar	4	Moderate
Apr	5	Moderate
May	6	High
Jun	6	High
Jul	8	Very high
Aug	3	Moderate
Sep	5	High
Oct	3	Moderate
Nov	2	Low
Dec	1	Low

Location & terrain

Where is Rock Forest?

Rock Forest sits at 45.4°N, 72.0°W, 240 m above sea level, in Canada. The nearest listed city is Sherbrooke, 9.0 km away.

Topography around Rock Forest

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Rock Forest.

Within 3 km, the terrain around Rock Forest has only modest variations in elevation — a maximum elevation change of 94 m around an average of 228 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 430 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,288 m.

The land around Rock Forest is covered by trees (68%) within 3 km, trees (66%) within 16 km, and trees (75%) within 80 km.

3 km

94 m

trees 68%

16 km

430 m

trees 66%

80 km

1,288 m

trees 75%

treesgrasslandcroplandartificial surfaceswater

← August Rock Forest year-round climate October →Best places to visit in September

September weather nearby: Sherbrooke 9.0 km · Magog 16 km · Granby 58 km · Drummondville 70 km · Victoriaville 77 km · Saint-Hyacinthe 81 km · Mont-Saint-Hilaire 96 km · Beloeil 97 km

Canada travel facts

Travel advisory: Level 1; Exercise Normal Precautions
Power plugs: Type A / B; 120 V · 60 Hz
Prices: ≈ 83% of US; price level, 2025
GDP per capita: $55,698; 2025
Happiness: 6.7 / 10; World Happiness, 2025
Safe drinking water: 97%; of population, 2024
Homicide rate: 2; per 100k, 2023
Road deaths: 5.3; per 100k/yr, 2019
Income group: High; World Bank
Religion

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Rock Forest (45.357°, -71.9968°, elevation 240 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).

	Avg high (°C)	Avg low (°C)
1	22	12
2	21	12
3	21	12
4	21	11
5	21	11
6	21	11
7	21	11
8	20	11
9	20	10
10	20	10
11	20	10
12	20	10
13	20	10
14	19	10
15	19	9
16	19	9
17	19	9
18	19	9
19	18	9
20	18	8
21	18	8
22	18	8
23	18	8
24	17	8
25	17	8
26	17	7
27	17	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	48	52
2	48	52
3	47	53
4	46	54
5	47	53
6	47	53
7	46	54
8	46	54
9	46	54
10	46	54
11	46	54
12	45	55
13	44	56
14	45	55
15	45	55
16	45	55
17	44	56
18	44	56
19	44	56
20	44	56
21	42	58
22	42	58
23	42	58
24	41	59
25	40	60
26	40	60
27	40	60
28	39	61
29	38	62
30	38	62

	Rain chance (%)
1	40
2	41
3	41
4	41
5	41
6	41
7	41
8	40
9	40
10	40
11	40
12	39
13	39
14	39
15	39
16	38
17	38
18	38
19	38
20	37
21	37
22	37
23	37
24	37
25	38
26	38
27	38
28	39
29	39
30	39

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	49	26	18	6
2	51	26	17	6
3	53	25	16	6
4	55	25	15	5
5	55	25	15	5
6	58	24	14	4
7	59	24	13	4
8	59	24	13	4
9	61	24	12	3
10	62	23	12	3
11	63	23	11	3
12	65	22	11	2
13	66	21	11	2
14	67	21	10	2
15	68	20	10	2
16	70	19	9	2
17	72	18	9	1
18	72	18	9	1
19	73	17	9	1
20	75	16	8	1
21	75	16	8	1
22	76	15	8	1
23	78	14	7	1
24	79	13	7	1
25	81	12	6	1
26	82	12	5	1
27	83	11	5	1
28	85	10	4	1
29	86	9	4	1
30	88	8	3	1

	Avg high (°C)	Avg low (°C)
1	22	12
2	21	12
3	21	12
4	21	11
5	21	11
6	21	11
7	21	11
8	20	11
9	20	10
10	20	10
11	20	10
12	20	10
13	20	10
14	19	10
15	19	9
16	19	9
17	19	9
18	19	9
19	18	9
20	18	8
21	18	8
22	18	8
23	18	8
24	17	8
25	17	8
26	17	7
27	17	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	48	52
2	48	52
3	47	53
4	46	54
5	47	53
6	47	53
7	46	54
8	46	54
9	46	54
10	46	54
11	46	54
12	45	55
13	44	56
14	45	55
15	45	55
16	45	55
17	44	56
18	44	56
19	44	56
20	44	56
21	42	58
22	42	58
23	42	58
24	41	59
25	40	60
26	40	60
27	40	60
28	39	61
29	38	62
30	38	62

	Rain chance (%)
1	40
2	41
3	41
4	41
5	41
6	41
7	41
8	40
9	40
10	40
11	40
12	39
13	39
14	39
15	39
16	38
17	38
18	38
19	38
20	37
21	37
22	37
23	37
24	37
25	38
26	38
27	38
28	39
29	39
30	39

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	49	26	18	6
2	51	26	17	6
3	53	25	16	6
4	55	25	15	5
5	55	25	15	5
6	58	24	14	4
7	59	24	13	4
8	59	24	13	4
9	61	24	12	3
10	62	23	12	3
11	63	23	11	3
12	65	22	11	2
13	66	21	11	2
14	67	21	10	2
15	68	20	10	2
16	70	19	9	2
17	72	18	9	1
18	72	18	9	1
19	73	17	9	1
20	75	16	8	1
21	75	16	8	1
22	76	15	8	1
23	78	14	7	1
24	79	13	7	1
25	81	12	6	1
26	82	12	5	1
27	83	11	5	1
28	85	10	4	1
29	86	9	4	1
30	88	8	3	1

	Avg high (°C)	Avg low (°C)
1	22	12
2	21	12
3	21	12
4	21	11
5	21	11
6	21	11
7	21	11
8	20	11
9	20	10
10	20	10
11	20	10
12	20	10
13	20	10
14	19	10
15	19	9
16	19	9
17	19	9
18	19	9
19	18	9
20	18	8
21	18	8
22	18	8
23	18	8
24	17	8
25	17	8
26	17	7
27	17	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	48	52
2	48	52
3	47	53
4	46	54
5	47	53
6	47	53
7	46	54
8	46	54
9	46	54
10	46	54
11	46	54
12	45	55
13	44	56
14	45	55
15	45	55
16	45	55
17	44	56
18	44	56
19	44	56
20	44	56
21	42	58
22	42	58
23	42	58
24	41	59
25	40	60
26	40	60
27	40	60
28	39	61
29	38	62
30	38	62

	Rain chance (%)
1	40
2	41
3	41
4	41
5	41
6	41
7	41
8	40
9	40
10	40
11	40
12	39
13	39
14	39
15	39
16	38
17	38
18	38
19	38
20	37
21	37
22	37
23	37
24	37
25	38
26	38
27	38
28	39
29	39
30	39

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	49	26	18	6
2	51	26	17	6
3	53	25	16	6
4	55	25	15	5
5	55	25	15	5
6	58	24	14	4
7	59	24	13	4
8	59	24	13	4
9	61	24	12	3
10	62	23	12	3
11	63	23	11	3
12	65	22	11	2
13	66	21	11	2
14	67	21	10	2
15	68	20	10	2
16	70	19	9	2
17	72	18	9	1
18	72	18	9	1
19	73	17	9	1
20	75	16	8	1
21	75	16	8	1
22	76	15	8	1
23	78	14	7	1
24	79	13	7	1
25	81	12	6	1
26	82	12	5	1
27	83	11	5	1
28	85	10	4	1
29	86	9	4	1
30	88	8	3	1