S
M
T
W
T
F
S
27
86°
70°
28
86°
70°
29
88°
70°
30
89°
69°
1
89°
69°
2
88°
68°
3
86°
69°
4
87°
68°
5
87°
68°
6
86°
67°
7
87°
65°
8
80°
59°
9
79°
57°
10
80°
58°
11
82°
57°
12
82°
59°
13
86°
64°
14
87°
64°
15
87°
63°
16
86°
64°
17
86°
64°
18
85°
63°
19
84°
64°
20
85°
63°
21
85°
61°
22
78°
56°
23
76°
58°
24
80°
61°
25
82°
62°
26
74°
47°
27
73°
51°
28
76°
58°
29
78°
60°
30
81°
59°
31
83°
48°
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 73° to 89°, with overnight lows between 47° and 70°. The average high for October is 83° with an average low of 62°. 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.
