Coastal Flood Advisory
Starts in 2 days 8 h
When
From 9 AM Monday to 3 PM PDT Thursday.
Where
Pacific 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 1.7 ft above normal (7.5 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: Coastal North Bay Including Point Reyes National Seashore; San Francisco Peninsula Coast
See it on weather.gov (opens in a new tab)

Observed 12:10 AM PDT at KSFO

Half Moon Bay, CA weather

Clear and 59°15°.

Mostly agree

Now 59°15°

Clear

Wind: Calm; Up to 6 mph10 km/h through 12 PM
Dew point: 52°11°; Comfortable · down to 43°6° by 4 AM
UV index: 0Low; Moderate 11 AM–5 PM · peak 5
Air quality: 47Good; Main pollutant: PM2.5 (fine particles)
Pressure: 30.03 inHg1017 hPa; Steady over the next 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Low 48°9° tonight at 5 AM
Above 60°16° today by 11 AM
High 66°19° today at 3 PM
Below 60°16° tonight after 7 PM
Fog tonight 11 PM–3 AM

TonightDown to 48°9° by 5 AM · Clear
This morningUp to 60°16° by 11 AM · Clear
This afternoonNear 64°18° · Clear
TonightDown to 48°9° by 4 AM · Partly cloudy
Tomorrow morningUp to 60°16° by 11 AM · Partly cloudy
Tomorrow afternoonNear 62°17° · Mostly cloudy
Tomorrow nightDown to 53°12° by 11 PM · Mostly 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 12a	Clear	53°12° (likely 53°12° to 57°14°)	53°12°	0%	2 mph3 km/h from NNW, gusts 3 mph5 km/h	86%	0%	0
Sat 1a	Clear	52°11° (likely 52°11° to 57°14°)	52°11°	0%	2 mph3 km/h from NNW, gusts 5 mph8 km/h	85%	1%	0
Sat 2a	Clear	51°11° (likely 51°11° to 56°13°)	51°11°	0%	2 mph3 km/h from NNW, gusts 4 mph6 km/h	84%	0%	0
Sat 3a	Clear	50°10° (likely 50°10° to 56°13°)	50°10°	0%	2 mph3 km/h from N, gusts 5 mph8 km/h	80%	1%	0
Sat 4a	Clear	49°9° (likely 49°9° to 55°13°)	49°9°	0%	2 mph3 km/h from NNE, gusts 5 mph7 km/h	80%	1%	0
Sat 5a	Clear	48°9° (likely 48°9° to 54°12°)	48°9°	0%	2 mph3 km/h from N, gusts 5 mph8 km/h	78%	2%	0
Sat 6a	Clear	48°9° (likely 48°9° to 54°12°)	48°9°	0%	2 mph3 km/h from NNE, gusts 5 mph8 km/h	76%	2%	0
Sat 7a	Sunny	48°9° (likely 48°9° to 53°12°)	48°9°	0%	2 mph3 km/h from NNE, gusts 5 mph8 km/h	76%	1%	0
Sat 8a	Sunny	48°9° (likely 48°9° to 54°12°)	47°8°	0%	3 mph5 km/h from NNE, gusts 5 mph8 km/h	76%	1%	0
Sat 9a	Sunny	54°12° (likely 54°12° to 57°14°)	54°12°	0%	5 mph8 km/h from NE, gusts 5 mph8 km/h	70%	2%	1
Sat 10a	Sunny	58°14° (likely 58°14° to 62°17°)	58°14°	0%	5 mph8 km/h from NNE, gusts 5 mph8 km/h	62%	1%	2
Sat 11a	Sunny	60°16° (likely 60°16° to 66°19°)	60°16°	0%	6 mph10 km/h from NNE, gusts 7 mph12 km/h	56%	1%	3
Sat 12p	Sunny	63°17° (likely 63°17° to 67°19°)	63°17°	0%	6 mph10 km/h from N, gusts 8 mph13 km/h	53%	1%	4
Sat 1p	Sunny	64°18° (likely 64°18° to 68°20°)	64°18°	0%	6 mph10 km/h from N, gusts 9 mph15 km/h	53%	0%	5
Sat 2p	Sunny	65°18° (likely 65°18° to 69°21°)	65°18°	0%	6 mph10 km/h from NNW, gusts 10 mph16 km/h	53%	0%	5
Sat 3p	Sunny	66°19° (likely 66°19° to 69°21°)	66°19°	0%	6 mph10 km/h from NW, gusts 10 mph15 km/h	54%	0%	4
Sat 4p	Sunny	65°18° (likely 65°18° to 69°21°)	65°18°	0%	7 mph11 km/h from NW, gusts 10 mph16 km/h	58%	0%	3
Sat 5p	Mostly sunny	65°18° (likely 65°18° to 68°20°)	65°18°	0%	6 mph10 km/h from NW, gusts 10 mph17 km/h	57%	14%	2
Sat 6p	Clear	62°17° (likely 62°17° to 65°18°)	63°17°	0%	5 mph8 km/h from NW, gusts 10 mph16 km/h	68%	26%	1
Sat 7p	Mostly clear	59°15° (likely 58°14° to 61°16°)	59°15°	0%	3 mph5 km/h from NNW, gusts 8 mph13 km/h	78%	12%	0
Sat 8p	Clear	57°14° (likely 56°13° to 59°15°)	57°14°	0%	2 mph3 km/h from WNW, gusts 6 mph9 km/h	82%	6%	0
Sat 9p	Partly cloudy	56°13° (likely 55°13° to 58°14°)	56°13°	0%	1 mph2 km/h from NNW, gusts 3 mph5 km/h	81%	25%	0
Sat 10p	Mostly clear	54°12° (likely 54°12° to 57°14°)	54°12°	0%	1 mph2 km/h from NNE, gusts 2 mph4 km/h	81%	45%	0
Sat 11p	Fog	53°12° (likely 53°12° to 56°13°)	53°12°	0%	0 mph0 km/h, gusts 3 mph4 km/h	82%	52%	0
Sun 12a	Fog	52°11° (likely 52°11° to 56°13°)	52°11°	0%	0 mph0 km/h, gusts 3 mph5 km/h	80%	54%	0
Sun 1a	Fog	51°11° (likely 51°11° to 55°13°)	51°11°	0%	0 mph0 km/h, gusts 2 mph4 km/h	80%	53%	0
Sun 2a	Fog	50°10° (likely 50°10° to 55°13°)	50°10°	0%	0 mph0 km/h, gusts 2 mph3 km/h	81%	46%	0
Sun 3a	Clear	49°9° (likely 49°9° to 55°13°)	49°9°	0%	0 mph0 km/h, gusts 3 mph4 km/h	82%	41%	0
Sun 4a	Partly cloudy	48°9° (likely 48°9° to 55°13°)	48°9°	0%	0 mph0 km/h, gusts 2 mph4 km/h	84%	51%	0
Sun 5a	Mostly cloudy	48°9° (likely 48°9° to 54°12°)	48°9°	0%	0 mph0 km/h, gusts 4 mph6 km/h	85%	51%	0
Sun 6a	Mostly cloudy	46°8° (likely 46°8° to 54°12°)	46°8°	0%	0 mph0 km/h, gusts 4 mph6 km/h	85%	46%	0
Sun 7a	Mostly cloudy	47°8° (likely 47°8° to 54°12°)	47°8°	0%	0 mph0 km/h, gusts 4 mph6 km/h	85%	55%	0
Sun 8a	Mostly cloudy	47°8° (likely 47°8° to 54°12°)	47°8°	0%	1 mph2 km/h from ENE, gusts 4 mph6 km/h	87%	55%	0
Sun 9a	Mostly cloudy	52°11° (likely 52°11° to 56°13°)	52°11°	0%	1 mph2 km/h from ENE, gusts 3 mph6 km/h	85%	51%	1
Sun 10a	Mostly cloudy	58°14° (likely 57°14° to 60°16°)	58°14°	0%	1 mph2 km/h from ENE, gusts 4 mph6 km/h	78%	59%	2
Sun 11a	Cloudy	60°16° (likely 60°16° to 63°17°)	60°16°	0%	3 mph5 km/h from WNW, gusts 4 mph7 km/h	74%	72%	3
Sun 12p	Mostly cloudy	62°17° (likely 61°16° to 65°18°)	62°17°	0%	3 mph5 km/h from WNW, gusts 5 mph8 km/h	71%	61%	4
Sun 1p	Mostly cloudy	63°17° (likely 62°17° to 66°19°)	63°17°	0%	3 mph5 km/h from WNW, gusts 6 mph10 km/h	71%	74%	4
Sun 2p	Cloudy	64°18° (likely 62°17° to 67°19°)	64°18°	0%	5 mph8 km/h from W, gusts 8 mph12 km/h	71%	76%	4
Sun 3p	Cloudy	65°18° (likely 62°17° to 67°19°)	65°18°	0%	5 mph8 km/h from W, gusts 9 mph14 km/h	71%	78%	4
Sun 4p	Cloudy	63°17° (likely 61°16° to 66°19°)	63°17°	0%	5 mph8 km/h from W, gusts 9 mph14 km/h	74%	83%	3
Sun 5p	Cloudy	62°17° (likely 59°15° to 65°18°)	62°17°	0%	2 mph3 km/h from W, gusts 8 mph14 km/h	74%	84%	2
Sun 6p	Cloudy	61°16° (likely 60°16° to 64°18°)	61°16°	0%	2 mph3 km/h from W, gusts 7 mph11 km/h	80%	86%	1
Sun 7p	Cloudy	59°15° (likely 58°14° to 60°16°)	59°15°	0%	2 mph3 km/h from W, gusts 5 mph8 km/h	84%	78%	0
Sun 8p	Mostly cloudy	56°13° (likely 56°13° to 58°14°)	56°13°	0%	0 mph0 km/h, gusts 5 mph7 km/h	86%	74%	0
Sun 9p	Mostly cloudy	55°13° (likely 55°13° to 58°14°)	55°13°	0%	0 mph0 km/h, gusts 5 mph8 km/h	88%	69%	0
Sun 10p	Mostly cloudy	54°12° (likely 54°12° to 57°14°)	54°12°	0%	0 mph0 km/h, gusts 5 mph8 km/h	90%	68%	0
Sun 11p	Mostly cloudy	53°12° (likely 53°12° to 57°14°)	53°12°	0%	1 mph2 km/h from W, gusts 4 mph7 km/h	90%	67%	0

Days ahead

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

Today, Oct 24. Mostly sunny. High 67°19°, low 46°8°. Typical 71°22° / 52°11°. Dry. Mostly agree. Best day outdoors this week.
1. Morning
  6 AM–noon
  Sunny, 48°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 48°9°
  Dry
Official NWS forecast
Today: Sunny. High near 67, with temperatures falling to around 65 in the afternoon. North wind 2 to 7 mph.
Tonight: Mostly clear. Low around 46, with temperatures rising to around 48 overnight. North wind around 2 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
Best day outdoors this week: the one dry, mild day the forecasts agree on (high 67°19°).
High, likely
67°19°–69°21°
Low, likely
46°8°–53°12°
Typical high / low
71°22° / 52°11°
Wind
9 mph14 km/h, gusts 15 mph24 km/h
UV peak
5
Tomorrow, Oct 25. Fog. High 66°19°, low 46°8°. Typical 71°22° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Mostly cloudy, 47°8°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 65°18°
  Dry
3. Evening
  6 PM–midnight
  Mostly cloudy, 56°13°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 55°13°
  Dry
Official NWS forecast
Day: Partly sunny, with a high near 66. Northwest wind 0 to 5 mph.
Night: Patchy fog after 2am. Mostly cloudy, with a low around 46. West southwest wind around 2 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
64°18°–67°19°
Low, likely
46°8°–53°12°
Typical high / low
71°22° / 52°11°
Wind
8 mph13 km/h, gusts 15 mph24 km/h
UV peak
4
Monday, Oct 26. Fog. High 62°17°, low 46°8°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Drizzle, 65°18°
  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: Patchy fog before 8am. Mostly sunny, with a high near 62.
Night: Partly cloudy, with a low around 46.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
62°17°–66°19°
Low, likely
46°8°–56°13°
Typical high / low
70°21° / 52°11°
Wind
12 mph19 km/h, gusts 22 mph36 km/h
UV peak
4
Tuesday, Oct 27. Cloudy. High 62°17°, low 48°9°. Typical 70°21° / 52°11°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 53°12°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 64°18°
  Dry
3. Evening
  6 PM–midnight
  Clear, 57°14°
  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 62.
Night: Mostly cloudy, with a low around 48.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
62°17°–66°19°
Low, likely
48°9°–53°12°
Typical high / low
70°21° / 52°11°
Wind
15 mph24 km/h
UV peak
5
Wednesday, Oct 28. Cloudy. High 61°16°, low 49°9°. Typical 70°21° / 52°11°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Partly sunny, 54°12°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Patchy fog before 9am. Mostly cloudy, with a high near 61.
Night: Mostly cloudy, with a low around 49.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
61°16°–64°18°
Low, likely
49°9°–55°13°
Typical high / low
70°21° / 52°11°
Wind
15 mph23 km/h
UV peak
4
Thursday, Oct 29. Rain. High 59°15°, low 49°9°. Typical 70°21° / 52°11°. Rain 0.01 in0.3 mm, 20% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 56°13°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 54°12°
  30% chance · 0.01 in0.3 mm
Hours this far out come from computer models only.
Official NWS forecast
Day: Patchy fog between 7am and 8am, then a slight chance of rain. Partly sunny, with a high near 59.
Night: A chance of rain. Mostly cloudy, with a low around 49.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
59°15°–66°19°
Low, likely
49°9°–56°13°
Typical high / low
70°21° / 52°11°
Wind
11 mph17 km/h, gusts 17 mph27 km/h
UV peak
4
Friday, Oct 30. Rain. High 59°15°, low 52°11°. Typical 69°21° / 51°11°. Rain 0.07 in1.8 mm, 40% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Drizzle, 54°12°
  30% chance · 0.02 in0.6 mm
2. Afternoon
  noon–6 PM
  Cloudy, 61°16°
  30% chance · 0.04 in0.9 mm
3. Evening
  6 PM–midnight
  Partly cloudy, 55°13°
  30% chance
4. Overnight
  midnight–6 AM
  Clear, 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 59.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
58°14°–63°17°
Low, likely
51°11°–54°12°
Typical high / low
69°21° / 51°11°
Wind
9 mph14 km/h, gusts 20 mph31 km/h
UV peak
4
Saturday, Oct 31. Cloudy. High 63°17°, low 50°10°. Typical 69°21° / 51°11°. Rain 0.03 in0.8 mm, 40% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 51°11°
  30% chance
2. Afternoon
  noon–6 PM
  Cloudy, 64°18°
  30% chance
3. Evening
  6 PM–midnight
  Clear, 57°14°
  30% chance
4. Overnight
  midnight–6 AM
  Cloudy, 51°11°
  30% chance
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°–69°21°
Low, likely
48°9°–52°11°
Typical high / low
69°21° / 51°11°
Wind
8 mph13 km/h, gusts 15 mph24 km/h
UV peak
3
Sunday, Nov 1. Cloudy. High 66°19°, low 50°10°. Typical 69°21° / 51°11°. Rain 0.01 in0.3 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 53°12°
  30% chance
2. Afternoon
  noon–6 PM
  Sunny, 66°19°
  30% chance
3. Evening
  6 PM–midnight
  Clear, 61°16°
  30% chance
4. Overnight
  midnight–6 AM
  Clear, 53°12°
  20% chance
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
63°17°–70°21°
Low, likely
47°8°–57°14°
Typical high / low
69°21° / 51°11°
Wind
12 mph19 km/h, gusts 18 mph29 km/h
UV peak
3
Monday, Nov 2. Cloudy. High 66°19°, low 54°12°. Typical 68°20° / 51°11°. Rain 0.02 in0.5 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Mostly sunny, 57°14°
  20% chance
2. Afternoon
  noon–6 PM
  Partly sunny, 67°20°
  30% chance
3. Evening
  6 PM–midnight
  Cloudy, 60°15°
  20% chance
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°–72°22°
Low, likely
52°11°–60°16°
Typical high / low
68°20° / 51°11°
Wind
8 mph13 km/h, gusts 20 mph32 km/h
UV peak
4

10 days15 days30 days

The outlook

Today
Dry, high 67°, low 46°.
Tomorrow
Dry, high 66°, low 46°.
Monday
Dry, high 62°, low 46°, cooling off.
Rest of week
Mostly dry, highs 59–66°.

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

Pilarcitos Creek at Half Moon Bay

0.3 mi

Level: 2.8 ft
Flow: 12 cfs

Reading from Fri 10 PM · NWS gauge page

Pilarcitos Creek below Stone Dam NR Hillsborough

4.6 mi

Level: 5.1 ft
Flow: 3 cfs

Reading from Fri 10 PM · NWS gauge page

Pilarcitos Creek above Stone Dam

4.8 mi

Level: 1.1 ft
Flow: 3 cfs

Reading from Fri 10:30 PM · NWS gauge page

Pilarcitos Creek below Pilarcitos Lake Spillway

5.7 mi

Level: 2.5 ft
Flow: 3 cfs

Reading from Fri 10:30 PM · NWS gauge page

For your home

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

Heating this week

About 35% less heating than a typical week.

This week 18Typical 28

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F: 3
h below 17°F: 0
h below 5°F: 0

47, 17 and 5°F are the test points heat pumps are rated at.

Comfort

Dry air outside (dew point 52°F).

Open the windows?

Today, 11:00 AM–6:00 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 4°2° colder than typical.

Last 7 days vs normal

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

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

Half Moon Bay 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 19 min less
Golden hour: 5:44–6:36 PM; Morning 7:10–8:02 AM
Blue hour: 6:36–6:47 PM; Morning 7:00–7:10 AM; first light 7:00 AM

Stars tonight? Good

Clear 12:39–7 AM; moon 96% lit, sets 5:48 AM.

Moon

Waxing gibbous

96% lit · growing

Today: sets 5:48 AM · rises 5:20 PM
Full moon: Oct 25
New moon: Nov 8

Looking southwest from Half Moon Bay. Open water to the horizon.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