Water temperature in Alcatraz
Sea surface temperature · updated today, Wednesday, October 28, at 10:44 pm (GMT-1)- Today
- 83.1–83.5 °F
- Air today
- 81 / 83 °F
- Tue 3
- 83.3 °F
- Wetsuit
- No wetsuit
Today the water in Alcatraz is 83.1 °F and ranges 83.1–83.5 °F through the day, with the air between 81 °F and 83 °F. It stays steady over the next few days.
Measured by satellite
This is the temperature satellites measured yesterday in the water just below the surface, at the nearest point of sea to Alcatraz (0.3 mi away), from NASA's MUR analysis, which sees the water in 1 km detail. It isn't a forecast: the big figure above is what a model gives for right now. On sunny afternoons the top of the water can be a little warmer.
Satellite: NASA MUR (JPL MUR MEaSUREs, PO.DAAC), doi:10.5067/GHGMR-4FJ04. Sources and licenses
The water over the next few days
- Today
- Thu 29
- Fri 30
- Sat 31
- Sun 1
- Mon 2
- Tue 3
- Wed 4
- Thu 5
- Fri 6
Water over the last 60 days
Over these days it has barely changed (from August 29).
Over the next few weeks the water looks a bit above normal (+1.3 °F), according to ECMWF 46-day.
Daily average and its range (low and high). The dotted line is the forecast.
Water temperature by month vs. normal
The water off Alcatraz is warmer than normal for late October today (+2.8 °F).
- 74.3° 74°JanJ
- 73.0° 73°FebF
- 72.8° 73°MarM
- 73.3° 73°AprA
- 73.8° 74°MayM
- 74.7° 75°JunJ
- 77.2° 77°JulJ
- 80.0° 80°AugA
- 81.0° 81°SepS
- 81.1° 81°OctO
- 79.6° 80°NovN
- 76.7° 77°DecD
- Monthly normal
- Today
In Alcatraz the water is pleasant year-round: 72.8–81.1 °F on average, depending on the month.
The water is warmest in October (81.1 °F on average) and coldest in March (72.8 °F).
Monthly averages for 1991–2020 (NOAA OISST, from satellites and buoys; nearest data point 5.5 mi away). Right by the shore, the water can be a little colder or warmer. Sources and licenses
Water and air, day by day
| Day | Water | Air | Max wave |
|---|---|---|---|
| Today | 83.1–83.5 °F | 81 / 83 °F | 3.5 ft |
| Thu 29 | 82.9–83.3 °F | 81 / 83 °F | 3.3 ft |
| Fri 30 | 82.9–83.5 °F | 81 / 82 °F | 3.3 ft |
| Sat 31 | 83.1–83.7 °F | 79 / 81 °F | 2.8 ft |
| Sun 1 | 83.1–84.0 °F | 79 / 80 °F | 2.8 ft |
| Mon 2 | 83.3–83.8 °F | 78 / 80 °F | 3.3 ft |
| Tue 3 | 83.1–83.5 °F | 78 / 80 °F | 3.2 ft |
Which wetsuit to wear
| Water | Wetsuit | How it feels |
|---|---|---|
| < 52 °F | 6/5 mm with hood, booties and gloves | Very cold: full kit only |
| 52°–57 °F | 5/4 mm with booties | Cold: takes your breath away |
| 57°–63 °F | 4/3 mm | Cool |
| 63°–66 °F | 3/2 mm | Mild |
| 66°–72 °F | Shorty (springsuit) | Pleasant |
| 72°–75 °F | Rash guard or top | Very pleasant |
| > 75 °F | No wetsuit | Warm |
A rough guide: it depends on the wind, how long you stay in and each person.
Fish are cold-blooded: the water sets their activity. Sudden temperature changes usually put them off the bite; with steady water, activity is more regular.
Previous days
The water over the last 60 days.
| Day | Water | Low / high |
|---|---|---|
| Tue 27 | 83.3 °F | 82.9–83.7 °F |
| Mon 26 | 83.1 °F | 82.9–83.5 °F |
| Sun 25 | 83.1 °F | 82.8–83.7 °F |
| Sat 24 | 82.8 °F | 82.6–82.9 °F |
| Fri 23 | 82.8 °F | 82.6–82.8 °F |
| Thu 22 | 82.6 °F | 82.4–82.8 °F |
| Wed 21 | 82.8 °F | 82.6–82.9 °F |
Show all 60 days
| Day | Water | Low / high |
|---|---|---|
| Tue 20 | 82.9 °F | 82.8–83.3 °F |
| Mon 19 | 83.1 °F | 82.9–83.5 °F |
| Sun 18 | 83.1 °F | 82.9–83.5 °F |
| Sat 17 | 83.3 °F | 83.1–83.7 °F |
| Fri 16 | 83.3 °F | 82.9–83.8 °F |
| Thu 15 | 83.1 °F | 82.9–83.5 °F |
| Wed 14 | 83.1 °F | 82.8–83.3 °F |
| Tue 13 | 83.1 °F | 82.8–83.5 °F |
| Mon 12 | 82.8 °F | 82.2–83.3 °F |
| Sun 11 | 82.8 °F | 82.4–82.9 °F |
| Sat 10 | 83.1 °F | 82.9–83.3 °F |
| Fri 9 | 83.3 °F | 83.3–83.5 °F |
| Thu 8 | 82.9 °F | 82.6–83.3 °F |
| Wed 7 | 82.9 °F | 82.6–83.3 °F |
| Tue 6 | 83.1 °F | 82.4–83.8 °F |
| Mon 5 | 82.9 °F | 82.6–83.5 °F |
| Sun 4 | 82.6 °F | 82.2–83.3 °F |
| Sat 3 | 82.4 °F | 82.2–82.9 °F |
| Fri 2 | 82.6 °F | 82.4–82.8 °F |
| Thu 1 | 83.1 °F | 82.8–83.5 °F |
| Wed 30 | 82.9 °F | 82.4–83.5 °F |
| Tue 29 | 82.9 °F | 82.2–83.8 °F |
| Mon 28 | 82.2 °F | 81.5–82.8 °F |
| Sun 27 | 82.4 °F | 82.0–82.8 °F |
| Sat 26 | 83.1 °F | 82.8–83.3 °F |
| Fri 25 | 83.1 °F | 82.9–83.3 °F |
| Thu 24 | 83.5 °F | 83.3–83.7 °F |
| Wed 23 | 83.5 °F | 83.3–83.8 °F |
| Tue 22 | 83.3 °F | 83.1–83.7 °F |
| Mon 21 | 83.1 °F | 82.9–83.3 °F |
| Sun 20 | 83.1 °F | 83.1–83.3 °F |
| Sat 19 | 83.1 °F | 82.9–83.3 °F |
| Fri 18 | 83.3 °F | 83.1–83.7 °F |
| Thu 17 | 84.0 °F | 83.7–84.4 °F |
| Wed 16 | 83.7 °F | 83.1–84.4 °F |
| Tue 15 | 83.3 °F | 83.1–83.5 °F |
| Mon 14 | 83.5 °F | 83.1–84.0 °F |
| Sun 13 | 83.3 °F | 82.8–83.8 °F |
| Sat 12 | 83.1 °F | 82.9–83.3 °F |
| Fri 11 | 83.5 °F | 83.1–83.8 °F |
| Thu 10 | 83.8 °F | 83.1–84.7 °F |
| Wed 9 | 83.7 °F | 83.3–83.8 °F |
| Tue 8 | 83.5 °F | 82.8–84.2 °F |
| Mon 7 | 83.7 °F | 83.1–84.4 °F |
| Sun 6 | 83.1 °F | 82.8–83.8 °F |
| Sat 5 | 83.1 °F | 82.9–83.5 °F |
| Fri 4 | 83.1 °F | 82.9–83.3 °F |
| Thu 3 | 83.1 °F | 82.9–83.7 °F |
| Wed 2 | 82.9 °F | 82.8–83.3 °F |
| Tue 1 | 82.9 °F | 82.8–83.3 °F |
| Mon 31 | 82.8 °F | 82.4–83.3 °F |
| Sun 30 | 82.8 °F | 82.4–83.1 °F |
| Sat 29 | 82.8 °F | 82.4–83.3 °F |
It's the daily analysis from Météo-France / Copernicus Marine (satellites, buoys and model), not a buoy reading at this spot.
Questions about the water in AlcatrazQuestions
What's the water temperature today in Alcatraz?
83.1 °F; through the day it ranges 83.1–83.5 °F.
Will the water get warmer or colder?
It stays steady over the next few days.
Which wetsuit do I need today?
With the water as it is today, no wetsuit (warm). It's a rough guide: it depends on the wind and each person.
How warm is the water in Alcatraz in October?
In October, the water in Alcatraz averages 81.1 °F (1991–2020), the warmest of the year. For a long swim: no wetsuit (warm).
When is the best time to swim in Alcatraz?
In Alcatraz the water is pleasant year-round: 72.8–81.1 °F on average, depending on the month. The water is warmest in October (81.1 °F on average) and coldest in March (72.8 °F).
Is the water warmer or colder than normal?
The water off Alcatraz is warmer than normal for late October today (+2.8 °F).
More about Alcatraz today
Water temperature near Alcatraz
- Calheta 82.9 °F · 7.4 mi
- Moia Moia 83.3 °F · 27 mi
- Cutelinho 82.8 °F · 29 mi
- Achada Monte 81.7 °F · 36 mi
Only places with a different forecast: spots a few miles apart share the same model cell and wouldn't add anything.
Learn more
Sea surface temperature: Open-Meteo with Météo-France / Copernicus Marine, CC BY 4.0; grid point 1.5 mi away. Near the shore, in coves and estuaries, the water can be a little colder or warmer.
Forecast from Open-Meteo (CC BY 4.0) with models from ECMWF, NOAA, Météo-France, DWD, Copernicus Marine and CAMS. Updated at 10:44 pm (local time).
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