Coastal Flood Advisory
Ends in 5 days 6 h
When
From 8 AM Saturday to 3 PM PDT Thursday.
Where
Bay Shoreline locations of San Francisco Bay, Monterey Bay and Big Sur Coast.
Issued for this forecast zone · National Weather Service San Francisco CA
What, impacts and precautionsHide details
What
Up to 1.9ft of inundation above ground level is possible in low-lying areas near shorelines and tidal waterways.
Impacts
High tides will result in flooding of low-lying infrastructure, isolated road closures, and coastal erosion. Rising tides will bring water and waves farther up the beach than normal, restricting escape from beaches and coastal areas.
Additional details
At the San Francisco tidal gauge, high tide is expected to be 1.1 ft above normal (6.9 ft MLLW) at 10:39 AM Saturday 10/24, 1.5 ft above normal (7.3 ft MLLW) at 11:07 AM Sunday 10/25, 1.6 ft above normal (7.4 ft MLLW) at 11:39 AM Monday 10/26, 1.8 ft above normal (7.6 ft MLLW) at 12:15 PM Tuesday 10/27, 1.9 ft above normal (7.7 ft MLLW) at 12:56 PM Wednesday 10/28, and 1.7 ft above normal (7.5 ft MLLW) at 01:43 PM Thursday 10/29. These predictions include up to 1.0 ft of surge that will enhance the astronomical tide and flooding threat. High tide varies up to 90 minutes earlier or later along the Pacific Coast and through the San Francisco Bay, respectively.
Precautionary actions
If travel is required, allow extra time as some roads may be closed. Do not drive around barricades or through water of unknown depth. Take the necessary actions to protect flood-prone property.
Areas: San Francisco; North Bay Interior Valleys; San Francisco Bay Shoreline; Northern Monterey Bay; Southern Monterey Bay and Big Sur Coast
See it on weather.gov (opens in a new tab)

Observed 8:25 AM PDT at KSFO

Foster City, CA weather

Sunny and 55°13°.

Mostly agree

Now 55°13°

Sunny

Wind: 5 mph8 km/h; From the east-southeast. 58–10 mph16 km/h through 8 PM
Dew point: 46°8°; Comfortable
UV index: 0Low; Moderate 11 AM–4 PM · peak 4
Air quality: 14Good; Main pollutant: PM2.5 (fine particles)
Pressure: 30.06 inHg1018 hPa; Steady over the last 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

4°2° cooler than this time yesterday (58°14° then, 54°12° now)

Good hours for

High 64°18° today at 3 PM

This morningUp to 59°15° by 11 AM · Clear
This afternoonUp to 64°18° by 3 PM · Clear
TonightDown to 56°13° by 3 AM · Clear
Tomorrow morningUp to 59°15° by 11 AM · Mostly cloudy
Tomorrow afternoonUp to 64°18° by 3 PM · Mostly cloudy
Tomorrow nightDown to 57°14° by 3 AM · Partly cloudy

Hourly forecast, next 48 hours, in the place's local time
Hour	Conditions	Temperature	Feels like	Precipitation	Wind	Humidity	Cloud cover	UV index
Sat 8a	Sunny	55°13° (likely 49°9° to 57°14°)	55°13°	0%	5 mph8 km/h from ESE, gusts 4 mph6 km/h	71%	1%	0
Sat 9a	Sunny	57°14° (likely 54°12° to 58°14°)	57°14°	0%	5 mph8 km/h from E, gusts 5 mph9 km/h	70%	2%	0
Sat 10a	Sunny	58°14° (likely 58°14° to 61°16°)	58°14°	0%	5 mph8 km/h from E, gusts 7 mph11 km/h	67%	0%	1
Sat 11a	Sunny	59°15° (likely 59°15° to 65°18°)	59°15°	0%	7 mph11 km/h from ENE, gusts 5 mph7 km/h	63%	0%	3
Sat 12p	Sunny	60°16° (likely 60°16° to 67°19°)	60°16°	0%	6 mph10 km/h from N, gusts 6 mph10 km/h	66%	0%	4
Sat 1p	Sunny	61°16° (likely 61°16° to 68°20°)	61°16°	0%	6 mph10 km/h from NW, gusts 6 mph10 km/h	67%	0%	4
Sat 2p	Sunny	62°17° (likely 62°17° to 71°22°)	62°17°	0%	7 mph11 km/h from NW, gusts 5 mph9 km/h	66%	0%	4
Sat 3p	Sunny	64°18° (likely 64°18° to 72°22°)	64°18°	0%	7 mph11 km/h from WNW, gusts 6 mph9 km/h	64%	0%	3
Sat 4p	Sunny	64°18° (likely 64°18° to 72°22°)	64°18°	0%	9 mph14 km/h from WNW, gusts 8 mph12 km/h	64%	0%	2
Sat 5p	Sunny	64°18° (likely 64°18° to 69°21°)	64°18°	0%	10 mph16 km/h from WNW, gusts 10 mph16 km/h	62%	0%	2
Sat 6p	Clear	63°17° (likely 63°17° to 66°19°)	63°17°	0%	10 mph16 km/h from WNW, gusts 11 mph17 km/h	66%	0%	1
Sat 7p	Clear	62°17° (likely 61°16° to 63°17°)	62°17°	0%	7 mph11 km/h from WNW, gusts 9 mph14 km/h	71%	0%	0
Sat 8p	Clear	61°16° (likely 58°14° to 62°17°)	61°16°	0%	6 mph10 km/h from WNW, gusts 8 mph13 km/h	74%	0%	0
Sat 9p	Clear	60°16° (likely 56°13° to 61°16°)	60°16°	0%	3 mph5 km/h from WNW, gusts 6 mph10 km/h	76%	0%	0
Sat 10p	Clear	60°16° (likely 55°13° to 60°16°)	60°16°	0%	2 mph3 km/h from W, gusts 5 mph7 km/h	76%	0%	0
Sat 11p	Clear	59°15° (likely 54°12° to 59°15°)	59°15°	0%	2 mph3 km/h from SW, gusts 3 mph5 km/h	76%	0%	0
Sun 12a	Clear	58°14° (likely 52°11° to 59°15°)	58°14°	0%	2 mph3 km/h from SSE, gusts 4 mph6 km/h	80%	0%	0
Sun 1a	Clear	58°14° (likely 51°11° to 58°14°)	58°14°	0%	2 mph3 km/h from S, gusts 3 mph5 km/h	80%	2%	0
Sun 2a	Clear	57°14° (likely 51°11° to 58°14°)	57°14°	0%	2 mph3 km/h from S, gusts 4 mph6 km/h	80%	36%	0
Sun 3a	Clear	56°13° (likely 50°10° to 58°14°)	56°13°	0%	1 mph2 km/h from S, gusts 4 mph6 km/h	80%	41%	0
Sun 4a	Mostly clear	56°13° (likely 49°9° to 58°14°)	56°13°	0%	1 mph2 km/h from SW, gusts 3 mph5 km/h	81%	43%	0
Sun 5a	Partly cloudy	56°13° (likely 49°9° to 57°14°)	56°13°	0%	1 mph2 km/h from NNE, gusts 2 mph4 km/h	81%	50%	0
Sun 6a	Partly cloudy	55°13° (likely 48°9° to 57°14°)	55°13°	0%	1 mph2 km/h from NNE, gusts 2 mph4 km/h	84%	50%	0
Sun 7a	Partly sunny	55°13° (likely 48°9° to 57°14°)	55°13°	0%	1 mph2 km/h from NNE, gusts 3 mph5 km/h	82%	60%	0
Sun 8a	Cloudy	55°13° (likely 48°9° to 56°13°)	55°13°	0%	2 mph3 km/h from E, gusts 4 mph6 km/h	85%	71%	0
Sun 9a	Cloudy	56°13° (likely 52°11° to 58°14°)	56°13°	0%	2 mph3 km/h from E, gusts 4 mph6 km/h	85%	76%	1
Sun 10a	Cloudy	58°14° (likely 56°13° to 60°16°)	58°14°	0%	2 mph3 km/h from E, gusts 3 mph5 km/h	85%	73%	2
Sun 11a	Partly sunny	59°15° (likely 59°15° to 62°17°)	59°15°	0%	3 mph5 km/h from NNW, gusts 4 mph6 km/h	84%	72%	3
Sun 12p	Cloudy	60°16° (likely 60°16° to 64°18°)	60°16°	0%	3 mph5 km/h from NNW, gusts 5 mph8 km/h	87%	70%	4
Sun 1p	Partly sunny	61°16° (likely 61°16° to 66°19°)	61°16°	0%	3 mph5 km/h from NNW, gusts 6 mph10 km/h	84%	79%	4
Sun 2p	Cloudy	62°17° (likely 62°17° to 68°20°)	62°17°	0%	7 mph11 km/h from WNW, gusts 8 mph13 km/h	81%	83%	4
Sun 3p	Cloudy	64°18° (likely 64°18° to 69°21°)	64°18°	0%	7 mph11 km/h from WNW, gusts 11 mph18 km/h	78%	79%	4
Sun 4p	Partly sunny	64°18° (likely 64°18° to 68°20°)	64°18°	0%	7 mph11 km/h from WNW, gusts 13 mph21 km/h	76%	75%	3
Sun 5p	Partly sunny	64°18° (likely 63°17° to 66°19°)	64°18°	0%	10 mph16 km/h from WNW, gusts 14 mph22 km/h	74%	77%	1
Sun 6p	Partly cloudy	63°17° (likely 60°16° to 64°18°)	63°17°	0%	10 mph16 km/h from WNW, gusts 14 mph23 km/h	77%	82%	0
Sun 7p	Cloudy	62°17° (likely 57°14° to 62°17°)	62°17°	0%	10 mph16 km/h from WNW, gusts 13 mph21 km/h	79%	85%	0
Sun 8p	Cloudy	60°16° (likely 56°13° to 60°16°)	60°16°	0%	5 mph8 km/h from W, gusts 12 mph19 km/h	81%	82%	0
Sun 9p	Cloudy	60°16° (likely 55°13° to 60°16°)	60°16°	0%	5 mph8 km/h from W, gusts 11 mph18 km/h	81%	76%	0
Sun 10p	Mostly clear	59°15° (likely 54°12° to 59°15°)	59°15°	0%	5 mph8 km/h from W, gusts 10 mph16 km/h	82%	25%	0
Sun 11p	Mostly clear	59°15° (likely 53°12° to 59°15°)	59°15°	0%	6 mph10 km/h from W, gusts 9 mph14 km/h	82%	33%	0
Mon 12a	Clear	58°14° (likely 52°11° to 58°14°)	59°15°	0%	6 mph10 km/h from W, gusts 9 mph14 km/h	85%	26%	0
Mon 1a	Clear	58°14° (likely 50°10° to 58°14°)	58°14°	0%	6 mph10 km/h from W, gusts 8 mph13 km/h	87%	29%	0
Mon 2a	Clear	58°14° (likely 49°9° to 58°14°)	58°14°	0%	5 mph8 km/h from SW, gusts 8 mph13 km/h	90%	31%	0
Mon 3a	Clear	57°14° (likely 50°10° to 57°14°)	57°14°	0%	5 mph8 km/h from SW, gusts 8 mph13 km/h	90%	36%	0
Mon 4a	Clear	57°14° (likely 50°10° to 57°14°)	57°14°	0%	5 mph8 km/h from SW, gusts 7 mph11 km/h	89%	37%	0
Mon 5a	Partly cloudy	57°14° (likely 51°11° to 57°14°)	57°14°	0%	5 mph8 km/h from SW, gusts 7 mph11 km/h	88%	61%	0
Mon 6a	Partly cloudy	56°13° (likely 51°11° to 57°14°)	57°14°	0%	5 mph8 km/h from SW, gusts 5 mph9 km/h	89%	55%	0
Mon 7a	Cloudy	56°13° (likely 51°11° to 57°14°)	56°13°	0%	5 mph8 km/h from SW, gusts 5 mph9 km/h	91%	70%	0

Days ahead

Shaded: typical range for these dates (1991–2020)

Today, Oct 24. Sunny. High 65°18°, low 55°13°. Typical 71°22° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Clear, 61°16°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 56°13°
  Dry
Official NWS forecast
Today: Sunny, with a high near 65. North northeast wind 5 to 10 mph.
Tonight: Mostly clear, with a low around 55. West southwest wind 1 to 10 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
65°18°–72°22°
Low, likely
48°9°–57°14°
Typical high / low
71°22° / 52°11°
Wind
9 mph15 km/h
UV peak
5
Tomorrow, Oct 25. Cloudy. High 65°18°, low 56°13°. Typical 71°22° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 57°14°
  Dry
Official NWS forecast
Day: Mostly sunny, with a high near 65. North northwest wind 1 to 10 mph.
Night: Partly cloudy, with a low around 56. West southwest wind 5 to 10 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
65°18°–69°21°
Low, likely
48°9°–56°13°
Typical high / low
71°22° / 52°11°
Wind
11 mph17 km/h, gusts 18 mph28 km/h
UV peak
4
Monday, Oct 26. Partly sunny. High 63°17°, low 55°13°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 54°12°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°15°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 54°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 63. West southwest wind 5 to 17 mph, with gusts as high as 23 mph.
Night: Mostly clear, with a low around 55.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–67°19°
Low, likely
50°10°–57°14°
Typical high / low
70°21° / 52°11°
Wind
11 mph17 km/h, gusts 23 mph36 km/h
UV peak
5
Tuesday, Oct 27. Partly sunny. High 64°18°, low 53°12°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Partly sunny, 53°12°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 65°18°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 52°11°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 64.
Night: Partly cloudy, with a low around 53.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
62°17°–66°19°
Low, likely
49°9°–55°13°
Typical high / low
70°21° / 52°11°
Wind
11 mph18 km/h, gusts 17 mph27 km/h
UV peak
5
Wednesday, Oct 28. Mostly cloudy. High 65°18°, low 54°12°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 52°11°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 58°15°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 65.
Night: Mostly cloudy, with a low around 54.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–66°19°
Low, likely
49°9°–55°13°
Typical high / low
70°21° / 52°11°
Wind
9 mph14 km/h
UV peak
4
Thursday, Oct 29. Cloudy. High 64°18°, low 53°12°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 56°13°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 54°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: A slight chance of rain after 5pm. Partly sunny, with a high near 64.
Night: A chance of rain. Partly cloudy, with a low around 53.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
61°16°–64°18°
Low, likely
53°12°–56°13°
Typical high / low
70°21° / 52°11°
Wind
11 mph17 km/h, gusts 24 mph38 km/h
UV peak
4
Friday, Oct 30. Rain. High 63°17°, low 53°12°. Typical 69°21° / 51°11°. Rain 0.01 in0.3 mm, 40% chance. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 53°12°
  20% chance
2. Afternoon
  noon–6 PM
  Sunny, 62°16°
  20% chance
3. Evening
  6 PM–midnight
  Cloudy, 56°13°
  20% chance
4. Overnight
  midnight–6 AM
  Cloudy, 51°11°
  30% chance
Hours this far out come from computer models only.
Official NWS forecast
Day: A chance of rain. Partly sunny, with a high near 63.
Night: A chance of rain. Mostly cloudy, with a low around 53.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
60°16°–63°17°
Low, likely
52°11°–53°12°
Typical high / low
69°21° / 51°11°
Wind
10 mph16 km/h, gusts 22 mph36 km/h
UV peak
4
Saturday, Oct 31. Cloudy. High 61°16°, low 50°10°. Typical 69°21° / 51°11°. Rain 0.03 in0.8 mm, 30% chance. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 51°11°
  20% chance
2. Afternoon
  noon–6 PM
  Sunny, 62°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 50°10°
  Dry
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
60°16°–66°19°
Low, likely
44°7°–54°12°
Typical high / low
69°21° / 51°11°
Wind
9 mph14 km/h, gusts 20 mph31 km/h
UV peak
4
Sunday, Nov 1. Sunny. High 64°18°, low 50°10°. Typical 69°21° / 51°11°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 51°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Clear, 60°15°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 53°12°
  Dry
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
59°15°–68°20°
Low, likely
43°6°–54°12°
Typical high / low
69°21° / 51°11°
Wind
13 mph20 km/h, gusts 30 mph48 km/h
UV peak
4
Monday, Nov 2. Cloudy. High 64°18°, low 56°13°. Typical 68°20° / 51°11°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 67°19°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 59°15°
  Dry
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
61°16°–70°21°
Low, likely
52°11°–62°17°
Typical high / low
68°20° / 51°11°
Wind
8 mph12 km/h, gusts 26 mph42 km/h
UV peak
3

10 days15 days30 days

The outlook

Today
Dry, high 65°, low 55°.
Tomorrow
Dry, high 65°, low 56°.
Monday
Dry, high 63°, low 55°.
Rest of week
Mostly dry, highs 61–65°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (MTR) (opens in a new tab)

What changed since yesterday

No meaningful changes from yesterday’s forecast.

Radar

Radar data: NOAA MRMS, rendered by forecast.blue

Radar loads when scrolled into view

Full-screen radar

Rivers

NOAA river gauges within 25 mi

Belmont Creek at Harbor Blvd at Old County Road

3.5 mi

Below flood stage

Level: 0.1 ft

Reading from Sat 4:16 AM · NWS gauge page

San Mateo Creek below Lower Crystal Springs Reservoir NR San Mateo

6.4 mi

Level: 4.2 ft
Flow: 4 cfs

Reading from Sat 7:30 AM · NWS gauge page

Lower Crystal Springs Reservoir at Dam

6.7 mi

Below flood stage

Level: 272 ft
Flow: 41,300 cfs

Reading from Sat 6:30 AM · NWS gauge page

Atherton Channel upstream of Caltrain

7.8 mi

Level: 0.1 ft

Reading from Sat 6:12 AM · NWS gauge page

For your home

What this week’s weather means for heating, cooling, pipes and fresh air.

Heating this week

About 60% less heating than a typical week.

This week 11Typical 28

Heating degree days, base 65°F

Comfort

Dry air outside (dew point 46°F).

Open the windows?

Today, 12:00 PM–10:00 PM

Good stretch to open the windows.

Is this typical?

San Francisco International Airport · official normals 1991–2020 · records 1945–2026

Oct 24, today vs a typical year

Today’s expected high is 6°3° colder than typical.

Last 7 days vs normal

On average 1°0° colder than normal (daily mean temperature).

−1°SunOct 18
−2°−1°MonOct 19
−1°TueOct 20
±0°WedOct 21
−1°ThuOct 22
+1°FriOct 23
—SatOct 24

Foster City weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 54 min; Losing 2 min 16 s a day; shortest Dec 21, 1 h 20 min less
Golden hour: 5:43–6:36 PM; Morning 7:09–8:02 AM
Blue hour: 6:36–6:46 PM; Morning 6:59–7:09 AM; first light 6:59 AM

Stars tonight? Fair

Mostly clear 6:46 PM–2 AM, but the moon is 99% lit and up.

Moon

Waxing gibbous

97% lit · growing

Today: sets 5:47 AM · rises 5:19 PM
Full moon: Oct 25
New moon: Nov 8

Looking northeast from Foster City. The highest point on the skyline is about 4,300 ft, 37 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.

1 active weather alert

Coastal Flood Advisory