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September weather forecast in Boulder
30 days
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
30 days
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Sun
Sunday
Mon
Monday
Tue
Tuesday
Wed
Wednesday
Thu
Thursday
Fri
Friday
Sat
Saturday
1
+22
+15
1 September, sun
+22
+15
Feels like
+18
648 mmHg
38%
5.5
m/s
SE
1 September, Sunday. day, 22°; night, 15°; partly cloudy
2
+21
+14
2 September, mon
+21
+14
Feels like
+17
648 mmHg
40%
5.8
m/s
E
2 September, Monday. day, 21°; night, 14°; partly cloudy
3
+21
+13
3 September, tue
+21
+13
Feels like
+18
648 mmHg
37%
5.3
m/s
W
3 September, Tuesday. day, 21°; night, 13°; partly cloudy
4
+20
+14
4 September, wed
+20
+14
Feels like
+17
647 mmHg
38%
5.5
m/s
SE
4 September, Wednesday. day, 20°; night, 14°; clear
5
+19
+13
5 September, thu
+19
+13
Feels like
+16
648 mmHg
43%
5.5
m/s
N
5 September, Thursday. day, 19°; night, 13°; clear
6
+20
+13
6 September, fri
+20
+13
Feels like
+16
648 mmHg
40%
5
m/s
SE
6 September, Friday. day, 20°; night, 13°; partly cloudy
7
+20
+12
7 September, sat
+20
+12
Feels like
+16
647 mmHg
40%
5
m/s
E
7 September, Saturday. day, 20°; night, 12°; clear
8
+20
+13
8 September, sun
+20
+13
Feels like
+16
647 mmHg
40%
5
m/s
SE
8 September, Sunday. day, 20°; night, 13°; clear
9
+19
+12
9 September, mon
+19
+12
Feels like
+15
648 mmHg
37%
5
m/s
SE
9 September, Monday. day, 19°; night, 12°; partly cloudy
10
+18
+11
10 September, tue
+18
+11
Feels like
+15
649 mmHg
46%
5.1
m/s
SE
10 September, Tuesday. day, 18°; night, 11°; clear
11
+17
+11
11 September, wed
+17
+11
Feels like
+14
649 mmHg
51%
4.6
m/s
E
11 September, Wednesday. day, 17°; night, 11°; clear
12
+18
+11
12 September, thu
+18
+11
Feels like
+15
647 mmHg
51%
5.3
m/s
SE
12 September, Thursday. day, 18°; night, 11°; clear
13
+17
+11
13 September, fri
+17
+11
Feels like
+14
647 mmHg
46%
5.5
m/s
E
13 September, Friday. day, 17°; night, 11°; clear
14
+16
+10
14 September, sat
+16
+10
Feels like
+13
648 mmHg
50%
6.1
m/s
E
14 September, Saturday. day, 16°; night, 10°; clear
15
+18
+12
15 September, sun
+18
+12
Feels like
+15
648 mmHg
40%
4.8
m/s
SE
15 September, Sunday. day, 18°; night, 12°; clear
16
+18
+12
16 September, mon
+18
+12
Feels like
+15
647 mmHg
38%
5.5
m/s
E
16 September, Monday. day, 18°; night, 12°; clear
17
+18
+11
17 September, tue
+18
+11
Feels like
+14
647 mmHg
40%
5.1
m/s
S
17 September, Tuesday. day, 18°; night, 11°; clear
18
+19
+12
18 September, wed
+19
+12
Feels like
+15
646 mmHg
34%
5.5
m/s
SW
18 September, Wednesday. day, 19°; night, 12°; clear
19
+19
+11
19 September, thu
+19
+11
Feels like
+15
647 mmHg
34%
5.4
m/s
SW
19 September, Thursday. day, 19°; night, 11°; clear
20
+18
+12
20 September, fri
+18
+12
Feels like
+13
647 mmHg
41%
5.4
m/s
SE
20 September, Friday. day, 18°; night, 12°; partly cloudy
21
+17
+11
21 September, sat
+17
+11
Feels like
+13
646 mmHg
43%
5.5
m/s
N
21 September, Saturday. day, 17°; night, 11°; clear
22
+16
+9
22 September, sun
+16
+9
Feels like
+11
647 mmHg
46%
5.8
m/s
E
22 September, Sunday. day, 16°; night, 9°; clear
23
+17
+11
23 September, mon
+17
+11
Feels like
+13
648 mmHg
41%
6.5
m/s
SE
23 September, Monday. day, 17°; night, 11°; clear
24
+17
+11
24 September, tue
+17
+11
Feels like
+13
647 mmHg
40%
5
m/s
S
24 September, Tuesday. day, 17°; night, 11°; rain
25
+18
+12
25 September, wed
+18
+12
Feels like
+14
647 mmHg
37%
5.3
m/s
E
25 September, Wednesday. day, 18°; night, 12°; clear
26
+17
+11
26 September, thu
+17
+11
Feels like
+13
648 mmHg
44%
5
m/s
E
26 September, Thursday. day, 17°; night, 11°; partly cloudy
27
+16
+11
27 September, fri
+16
+11
Feels like
+13
649 mmHg
44%
5.3
m/s
SE
27 September, Friday. day, 16°; night, 11°; rain
28
+16
+10
28 September, sat
+16
+10
Feels like
+12
649 mmHg
43%
5.5
m/s
SE
28 September, Saturday. day, 16°; night, 10°; clear
29
+17
+10
29 September, sun
+17
+10
Feels like
+12
647 mmHg
37%
6.5
m/s
W
29 September, Sunday. day, 17°; night, 10°; clear
30
+16
+9
30 September, mon
+16
+9
Feels like
+11
647 mmHg
41%
5
m/s
S
30 September, Monday. day, 16°; night, 9°; rain
1
+14
+8
1 October, tue
+14
+8
Feels like
+9
647 mmHg
47%
6
m/s
N
1 October, Tuesday. day, 14°; night, 8°; partly cloudy
2
+14
+9
2 October, wed
+14
+9
Feels like
+10
646 mmHg
43%
5.3
m/s
S
2 October, Wednesday. day, 14°; night, 9°; rain
3
+14
+6
3 October, thu
+14
+6
Feels like
+10
645 mmHg
50%
5.4
m/s
W
3 October, Thursday. day, 14°; night, 6°; clear
4
+12
+6
4 October, fri
+12
+6
Feels like
+7
645 mmHg
49%
4.8
m/s
SW
4 October, Friday. day, 12°; night, 6°; partly cloudy
5
+11
+5
5 October, sat
+11
+5
Feels like
+7
646 mmHg
47%
4.9
m/s
W
5 October, Saturday. day, 11°; night, 5°; partly cloudy
Average data for 10 years
Boulder September
20
sunny days
3
days with precipitation
7
cloudy days
20 sunny days; 3 days with precipitation; 7 cloudy days;
41
%
air humidity
3.7
m/s
Wind
SE
53
mm of precipitation
(10% of annual average)
air humidity 41%; 53 millimeters of precipitation (10% of annual average); Wind south-easterly 3.7 Meters per second
Weather graphs for September
Temperature
Precipitation chance, %
Humidity, %
Wind, m/s
Pressure, mmHg
SE
E
W
SE
N
SE
E
SE
SE
SE
E
SE
E
E
SE
E
S
SW
SW
SE
N
E
SE
S
E
E
SE
SE
W
S
1
Average data for 10 years
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
Daytime temperature
Night-time temperature
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