S
M
T
W
T
F
S
29
-15°
-30°
30
-16°
-32°
31
-12°
-28°
1
-8°
-21°
2
-1°
-17°
3
7°
-14°
4
2°
-9°
5
-2°
-14°
6
0°
-11°
7
-3°
-16°
8
5°
-20°
9
-11°
-20°
10
-5°
-19°
11
-8°
-22°
12
-7°
-23°
13
6°
-27°
14
8°
-9°
15
13°
-9°
16
5°
-7°
17
1°
-12°
18
5°
-8°
19
2°
-10°
20
-1°
-10°
21
4°
-9°
22
12°
2°
23
15°
7°
24
14°
9°
25
18°
3°
26
12°
-4°
27
14°
5°
28
17°
7°
29
19°
7°
30
12°
2°
1
19°
12°
2
20°
9°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
April Weather in Fullerton
Fullerton's April 2026 forecast shows daily high temperatures ranging from 12° to 20°, with overnight lows between -4° and 12°. The average high for April is 16° with an average low of 5°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how April weather will actually feel in Fullerton. See also: May | June | July.
