San Francisco Weather

2026 (This Year)

Historical data
Average Temperature
18.7 °C
High
/
11.9 °C
Low
348.7mm
Precipitation
33.6°C
Peak Temp
5.2°C
Low Temp
282
Days Count

Seasonal Breakdown

Average temperatures and precipitation by season

Spring

92 days
19.4°C
Avg High
/
11.6°C
Avg Low
Precipitation
148.3mm

Summer

92 days
18.8°C
Avg High
/
13.2°C
Avg Low
Precipitation
7.5mm

Autumn

39 days
21.4°C
Avg High
/
14.2°C
Avg Low
Precipitation
6.7mm

Winter

59 days
15.5°C
Avg High
/
8.6°C
Avg Low
Precipitation
186.2mm

Seasons based on meteorological calendar: Spring (Mar-May), Summer (Jun-Aug), Autumn (Sep-Nov), Winter (Dec-Feb)

Monthly Breakdown

Average temperatures and precipitation by month

January

31 days
15.0°C / 8.1°C
Avg High / Low
Precipitation
74.3mm

February

28 days
16.2°C / 9.2°C
Avg High / Low
Precipitation
111.9mm

March

31 days
22.5°C / 11.4°C
Avg High / Low
Precipitation
9.4mm

April

30 days
17.8°C / 11.5°C
Avg High / Low
Precipitation
117.7mm

May

31 days
18.0°C / 12.0°C
Avg High / Low
Precipitation
21.2mm

June

30 days
18.9°C / 12.7°C
Avg High / Low
Precipitation
1.0mm

July

31 days
18.5°C / 13.0°C
Avg High / Low
Precipitation
5.2mm

August

31 days
19.0°C / 14.1°C
Avg High / Low
Precipitation
1.3mm

September

30 days
20.8°C / 14.3°C
Avg High / Low
Precipitation
6.7mm

October

9 days
23.4°C / 14.1°C
Avg High / Low
Precipitation
0.0mm

Temperature Trends

Daily high, low, and average

Weather Extremes

Most notable conditions during this period

Period High

33.6°C
Wednesday, September 9

Coolest Day

10.1°C
Wednesday, February 18

Period Low

5.2°C
Friday, February 20

Compare with historical weather

Load the same period from the previous 15 years.

Weather Insights

Key findings from analysis for selected period

Highly Variable Temperatures

Worth noting

Temperature swings from 5.2°C to 33.6°C (28.4°C range).

📅

Seasonal Weather Patterns

Info
Rainfall Patterns:
Wettest: April (118mm), February (112mm)
Driest: June (1mm), August (1mm)

Temperature Patterns (Monthly Averages):
Hottest months: March (22.5°C), September (20.8°C)
Coolest months: January (15.0°C), February (16.2°C)

Travel Recommendations:
Best visiting months: March, October, September (optimal temperature and rainfall balance).
⚠️

3 Exceptional Weather Events

Info

The most extreme days in this period:

Sep 9 Heat

Hottest day: 33.6°C

Feb 16 Rain

Heavy rain: 30.2mm in one day

Apr 20 Rain

Heavy rain: 43.0mm in one day

1 Extreme Heat Index Day

Worth noting

1 day with dangerous heat index levels (44.3°C average). Temperature 33.0°C combined with 72% humidity creates hazardous conditions.

High Humidity Levels

Info

Average humidity of 77% indicates persistently moist air conditions. Heat sensation amplified during warm periods (18.7°C average temperature). Humidity varied significantly (22%-95% range).

📊

Highly Variable Humidity

Info

Large humidity swings (22%-95%) for a year. Conditions ranged from very dry to very humid.

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Global Weather Data

Features

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Data Source

Weather data provided by Open-Meteo, offering reliable historical weather information from meteorological stations worldwide.

Data accuracy and availability may vary by location and time period.

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