Boca de Quadra, AK tide times
NOAA tide prediction station 9450305, 55.1167° N, 130.7980° W. Heights in feet above MLLW.
Today at Boca de Quadra, AK
Today's predicted high and low waters, sunrise and sunset for Boca de Quadra, AK load here from NOAA. Without JavaScript they cannot be shown: NOAA's own table for station 9450305 is at tidesandcurrents.noaa.gov. Everything else on this page is measured and does not change from day to day.
What the tide does at Boca de Quadra, AK
Across the 1411 high and low waters NOAA predicts here for 2027, high water averages 14.1 ft above MLLW and low water 1.7 ft — a mean range of 12.4 ft. Taking each day's higher high and lower low, which is the swing someone standing on the shore actually sees, the average is 14.85 ft.
On 93% of days in 2027 there are two high waters and on the remaining 25 days only one. Where there are two, they differ in height by 1.93 ft on average. Successive high waters are 12h 25m apart on average.
The largest daily swing of 2027 is 22.48 ft on 23 January 2027 and the smallest is 5.24 ft on 5 November 2027 , a factor of 4.3 between the biggest spring tide and the smallest neap.
Measured figures
| Mean high water | 14.1 ft above MLLW |
|---|---|
| Mean low water | 1.7 ft above MLLW |
| Mean range | 12.4 ft |
| Mean great diurnal range | 14.85 ft |
| Largest daily range in 2027 | 22.48 ft on 23 January 2027 |
| Smallest daily range in 2027 | 5.24 ft on 5 November 2027 |
| Highest predicted tide | 18.61 ft at 1:03 PM on 23 January 2027 |
| Lowest predicted tide | -4.24 ft at 8:26 AM on 5 July 2027 |
| Average gap between high waters | 12h 25m |
| Tidal pattern | semidiurnal (1.93 high waters a day) |
| Position | 55.1167° N, 130.7980° W |
| NOAA station id | 9450305 |
Every figure above is computed from NOAA's published predictions for station 9450305 for the whole of 2027 (365 days, 1411 tides), not from a regional average or an estimate.
What MLLW means here
Every height on this page is feet above MLLW — mean lower low water, the chart datum NOAA publishes tide predictions against. It is the average of the lower of each day's low waters, taken over a 19-year period, so zero here is neither the sea bed nor the average sea level: it is a level the water drops below regularly. At Boca de Quadra, AK, 199 of the 706 low waters predicted for 2027 — 28% of them — fall below zero, the lowest being -4.24 ft on 5 July 2027.
Practically: a chart showing 6 ft of water here means about 6 ft at a mean lower low water and about 20.9 ft at a mean higher high. Add the predicted height for the moment you care about to the charted depth.
Where these predictions come from
This is a subordinate station. NOAA does not run a separate harmonic analysis here; it takes the predictions for Ketchikan, AK, 58 km (36 miles) away and shifts them. High water arrives at the same time as the reference station and low water 2 min later than it. Heights are the reference station's multiplied by 0.98 at high water and 0.98 at low water.
Those constants are NOAA's own, published for station 9450305 (reference 9450460). They are why a subordinate station's table is never simply its neighbour's.
Daylight at this latitude
Boca de Quadra, AK sits at 55.1167° N. The longest day of 2027 here is 17h 24m of daylight on 21 June 2027; the shortest is 7h 08m on 21 December 2027 — a difference of 10h 16m.
Day lengths are computed with NOAA's published solar algorithm from the station's latitude and longitude. Clock times for sunrise and sunset are deliberately not printed here: they depend on the station's UTC offset, and this site takes that offset from NOAA's own answers rather than from a timezone table — so it is the live panel above, which has them, that shows the times.
Nearest other stations
- Kah Shakes Cove, AK 14 km (8.9 miles)
- Alva Bay, Revillagigedo Island, AK 25 km (15 miles)
- Custom House Cove, Mary Island, AK 27 km (17 miles)
- Nakat Harbor, Alaska, AK 34 km (21 miles)
- Hidden Inter Entrance, Pearse Inlet, AK 35 km (22 miles)
- Morse Cove, Duke Island, AK 36 km (23 miles)
Put these tides on your own site
One line of HTML shows today's tides for Boca de Quadra, AK on any page:
<script src="https://tidedata.romermade.com/v1/embed.js" data-station="9450305" defer></script>No account, no key, no build step. How it works.