5-day weather forecast San Francisco Sep 20, 2026
16°Weather forecast San Francisco Sunday Sep 20, 2026: overcast, temperature from 14 °C to 16 °C.
Precipitation probability 29%. Wind up to 6.81 m/s (gusts 8.83 m/s). Air humidity 81–89%, atmospheric pressure 759–761 mm Hg, UV index up to 5.
Weather Alerts
Small Craft Advisory issued September 15 at 8:42PM PDT until September 16 at 9:00PM PDT by NWS San Francisco CA
Small Craft Advisory
* WHAT...West winds 10 to 15 kt with gusts up to 25 kt and choppy
waters expected.
* WHERE...San Francisco Bay South of the Bay Bridge.
* WHEN...From 9 AM to 9 PM PDT Wednesday.
* IMPACTS...Conditions will be hazardous to small craft.
Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.
Small Craft Advisory issued September 15 at 2:17PM PDT until September 16 at 9:00PM PDT by NWS San Francisco CA
Small Craft Advisory
* WHAT...West winds 10 to 15 kt with gusts to 25 kt and choppy
waters expected.
* WHERE...San Francisco Bay South of the Bay Bridge.
* WHEN...From 9 AM to 9 PM PDT Wednesday.
* IMPACTS...Conditions will be hazardous to small craft.
Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.
5 days at a glance — tap a day to open it
Sunrise 06:55
Sunset 19:10
Sunset 19:10
Waxing Gibbous73% illuminated
Moonrise 16:24 · Moonset 01:05
Moonrise 16:24 · Moonset 01:05
Chart
Table
Sun, Sep 20, 2026
| Time | Weather | Temperature | Rain chance | Cloud cover | Humidity | Pressure | Wind | UV Index |
|---|---|---|---|---|---|---|---|---|
| 00:00 |  Overcast | 15 °C | 27% | 96% | 88% | 761 mm Hg | W 268° 5.81 (7.64) m/s | 0 |
| 01:00 |  Cloudy | 15 °C | 22% | 73% | 87% | 761 mm Hg | W 270° 5.69 (7.33) m/s | 0 |
| 02:00 | Overcast | 15 °C | 28% | 100% | 86% | 761 mm Hg | W 271° 5.61 (7.22) m/s | 0 |
| 03:00 |  Patchy rain possible | 15 °C | 20% (0.01 mm/hr) | 65% | 87% | 761 mm Hg | W 277° 6.19 (8.11) m/s | 0 |
| 04:00 | Patchy rain possible | 15 °C | 23% (0.01 mm/hr) | 74% | 87% | 761 mm Hg | W 281° 6.81 (8.83) m/s | 0 |
| 05:00 | Patchy rain possible | 15 °C | 29% (0.02 mm/hr) | 100% | 86% | 761 mm Hg | W 275° 5.31 (6.72) m/s | 0 |
| 06:00 | Patchy rain possible | 15 °C | 27% | 100% | 86% | 761 mm Hg | W 274° 5.11 (6.5) m/s | 0 |
| 07:00 |  Patchy rain possible | 15 °C | 27% | 100% | 86% | 761 mm Hg | W 274° 4.89 (6.19) m/s | 3 |
| 08:00 | Patchy rain possible | 15 °C | 28% (0.01 mm/hr) | 100% | 86% | 761 mm Hg | W 273° 4.69 (5.92) m/s | 3 |
| 09:00 | Overcast | 15 °C | 26% | 100% | 84% | 761 mm Hg | W 263° 4.5 (5.39) m/s | 4 |
| 10:00 | Patchy rain possible | 15 °C | 25% | 99% | 83% | 761 mm Hg | WSW 253° 4.19 (4.81) m/s | 4 |
| 11:00 | Overcast | 16 °C | 24% | 98% | 81% | 761 mm Hg | WSW 243° 4 (4.31) m/s | 4 |
| 12:00 | Overcast | 16 °C | 24% | 99% | 81% | 761 mm Hg | WSW 245° 4.39 (4.69) m/s | 4 |
| 13:00 | Overcast | 16 °C | 24% | 100% | 81% | 761 mm Hg | WSW 247° 4.89 (5.11) m/s | 4 |
| 14:00 | Overcast | 16 °C | 25% | 100% | 81% | 760 mm Hg | WSW 249° 5.31 (5.5) m/s | 4 |
| 15:00 |  Partly cloudy | 16 °C | 22% | 85% | 82% | 760 mm Hg | WSW 252° 5.39 (5.81) m/s | 5 |
| 16:00 | Overcast | 16 °C | 19% | 70% | 82% | 760 mm Hg | WSW 256° 5.39 (6) m/s | 4 |
| 17:00 | Partly cloudy | 16 °C | 16% | 55% | 83% | 759 mm Hg | W 260° 5.5 (6.31) m/s | 5 |
| 18:00 |  Cloudy | 15 °C | 18% | 61% | 85% | 759 mm Hg | W 260° 5.39 (6.19) m/s | 4 |
| 19:00 | Partly cloudy | 15 °C | 20% | 66% | 87% | 759 mm Hg | W 259° 5.31 (6.11) m/s | 4 |
| 20:00 | Cloudy | 15 °C | 23% | 72% | 89% | 760 mm Hg | W 259° 5.19 (6.03) m/s | 0 |
| 21:00 | Cloudy | 15 °C | 22% | 73% | 88% | 759 mm Hg | WSW 255° 5 (5.81) m/s | 0 |
| 22:00 | Cloudy | 14 °C | 23% | 74% | 88% | 759 mm Hg | WSW 251° 4.89 (5.5) m/s | 0 |
| 23:00 | Cloudy | 14 °C | 23% | 74% | 88% | 759 mm Hg | WSW 246° 4.69 (5.25) m/s | 0 |
Sun, Sep 20, 2026
San Francisco on the map
Data Sources & Methodology
Our weather forecasts are powered by a professional weather data provider that aggregates data from national weather services, satellite observations, radar networks, and over 80,000 weather stations worldwide. Forecast data is updated multiple times daily. We convert raw data into clear summaries — wind speed in m/s, pressure in mmHg — so you can plan your day with confidence.