When to go · San Mateo
San Mateo in September
Great month. Inside San Mateo's best window: Apr–Jun, Sep–Oct.
Key facts
- Verdict
- Great
- Temperature
- 25°C (77°F)77°F (25°C) / 13°C (55°F)55°F (13°C)
- average high / low
- Rain days
- 2
- Crowds
- Medium
- United States overall
- Prices
- Medium
- United States overall
Verdict
Inside San Mateo's best window: Apr–Jun, Sep–Oct.
Is another month better than September?
No other month rates higher than September for San Mateo in this guide.
Weather in September
- San MateoHighs around 25 °C (77 °F), lows around 13 °C (55 °F), rain on about 2 daysHighs around 77 °F (25 °C), lows around 55 °F (13 °C), rain on about 2 days
Festivals and holidays
Dates as our data lists them. Moving holidays (lunar and Islamic calendars, Easter) shift every year: check the date for your year before you build a trip on it.
Labor Day big impact
1st Monday of September · United States
End of summer; last big road-trip weekend.
Crowds and prices
- Crowds · United States overall
- Medium
- Prices · United States overall
- Medium
United States overall: After Labor Day the crowds drop and parks stay open; Florida and the Gulf are at hurricane peak.
Compare two months
Weather, crowds and prices for any two months in San Mateo, side by side.
Verdict
Sep: Great
Apr: Great
Daytime high
Sep: 25 °C (77 °F)77 °F (25 °C)
Apr: 19 °C (66 °F)66 °F (19 °C)
Night low
Sep: 13 °C (55 °F)55 °F (13 °C)
Apr: 9 °C (48 °F)48 °F (9 °C)
Rain days
Sep: 2 (better)
Apr: 6
Crowds
Sep: Medium
Apr: Medium
Prices
Sep: Medium
Apr: Medium
Festivals listed
Sep: 1
Apr: 1
September: Inside San Mateo's best window: Apr–Jun, Sep–Oct.
April: Inside San Mateo's best window: Apr–Jun, Sep–Oct.
San Mateo: figures are long-term averages from this guide, not a forecast.
What to pack
Nothing unusual for the weather this month.