The temperatures in Vallejo in September are comfortable with low of 59°F and and high up to 82°F.
You can expect up to 3 rainy days in Vallejo during the month of September.
Our weather forecast can give you a great sense of what weather to expect in Vallejo in September 2025.
If you’re planning to visit Vallejo in the near future, we highly recommend that you review the 14 day weather forecast for Vallejo before you arrive.
Temperatures
82° / 59°
Rainy Days
0
Snowy Days
0
Dry Days
30
Rainfall
0.12
in
Sun Hours
11.9
Hrs
