S
M
T
W
T
F
S
27
N/A
28
98°
69°
29
97°
71°
30
94°
77°
1
86°
73°
2
79°
73°
3
78°
73°
4
79°
73°
5
90°
69°
6
91°
65°
7
92°
61°
8
93°
64°
9
92°
61°
10
92°
57°
11
93°
65°
12
91°
69°
13
96°
79°
14
96°
77°
15
92°
68°
16
74°
56°
17
70°
50°
18
75°
45°
19
82°
49°
20
85°
53°
21
86°
51°
22
88°
55°
23
86°
54°
24
88°
54°
25
83°
58°
26
80°
53°
27
82°
66°
28
81°
67°
29
73°
63°
30
75°
66°
31
81°
66°
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 82°, with overnight lows between 63° and 67°. The average high for October is 78° with an average low of 66°. 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.
