S
M
T
W
T
F
S
27
87°
71°
28
N/A
29
82°
59°
30
89°
61°
1
90°
57°
2
103°
65°
3
102°
79°
4
102°
72°
5
103°
72°
6
103°
71°
7
100°
63°
8
87°
62°
9
85°
64°
10
78°
66°
11
74°
62°
12
69°
55°
13
77°
56°
14
81°
58°
15
86°
60°
16
89°
61°
17
86°
60°
18
86°
61°
19
84°
62°
20
85°
61°
21
79°
56°
22
82°
59°
23
83°
60°
24
82°
60°
25
82°
59°
26
81°
60°
27
81°
59°
28
80°
59°
29
80°
58°
30
79°
58°
31
79°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
October Weather in San Marcos
San Marcos's October 2026 forecast shows daily high temperatures ranging from 69° to 89°, with overnight lows between 55° and 66°. The average high for October is 81° with an average low of 60°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how October weather will actually feel in San Marcos. See also: November | December | January.
