PAINTED SHORES
MENUBegin
CA · NOAA 9415020 · 37° 60′ N · 122° 58′ W
Tides at Point Reyes
A mixed, mainly semidiurnal tide (form factor 0.90), spring this week. Predicted from the station's 31 harmonic constants; heights above mean lower low water, times in station time. Weather is not in these numbers.
This week
| When | Water | Height |
|---|---|---|
| Sun, Oct 25, 5:10 PM | Low | -0.3 ft |
| Sun, Oct 25, 11:36 PM | High | 4.9 ft |
| Mon, Oct 26, 4:48 AM | Low | 2.1 ft |
| Mon, Oct 26, 10:50 AM | High | 6.5 ft |
| Mon, Oct 26, 5:55 PM | Low | -0.8 ft |
| Tue, Oct 27, 12:31 AM | High | 4.8 ft |
| Tue, Oct 27, 5:26 AM | Low | 2.5 ft |
| Tue, Oct 27, 11:26 AM | High | 6.7 ft |
| Tue, Oct 27, 6:43 PM | Low | -1.1 ft |
| Wed, Oct 28, 1:29 AM | High | 4.6 ft |
| Wed, Oct 28, 6:07 AM | Low | 2.9 ft |
| Wed, Oct 28, 12:06 PM | High | 6.7 ft |
| Wed, Oct 28, 7:34 PM | Low | -1.2 ft |
| Thu, Oct 29, 2:32 AM | High | 4.5 ft |
| Thu, Oct 29, 6:54 AM | Low | 3.2 ft |
| Thu, Oct 29, 12:52 PM | High | 6.6 ft |
| Thu, Oct 29, 8:29 PM | Low | -1.0 ft |
| Fri, Oct 30, 3:42 AM | High | 4.4 ft |
| Fri, Oct 30, 7:50 AM | Low | 3.4 ft |
| Fri, Oct 30, 1:46 PM | High | 6.2 ft |
| Fri, Oct 30, 9:30 PM | Low | -0.8 ft |
| Sat, Oct 31, 4:54 AM | High | 4.5 ft |
| Sat, Oct 31, 9:05 AM | Low | 3.5 ft |
| Sat, Oct 31, 2:50 PM | High | 5.8 ft |
| Sat, Oct 31, 10:35 PM | Low | -0.5 ft |
| Sun, Nov 1, 4:58 AM | High | 4.7 ft |
| Sun, Nov 1, 9:42 AM | Low | 3.4 ft |
The constants that make it
| Constituent | Amplitude | Phase |
|---|---|---|
| M2 | 1.8 ft | 190.4° |
| K1 | 1.3 ft | 219.9° |
| O1 | 0.8 ft | 204.1° |
| S2 | 0.4 ft | 196.3° |
| N2 | 0.4 ft | 164.1° |
| P1 | 0.4 ft | 215.0° |
| SA | 0.2 ft | 213.3° |
| Q1 | 0.1 ft | 196.7° |
The eight largest of 31. Source: NOAA CO-OPS harmonic constituents for 9415020, public domain.
The year as a print
The last two days, measured
At Sun, Oct 25 13:24 the gauge read 4.8 ft, 1.3 ft above the computed curve: wind and pressure, not the moon. The widest gap of the two days was 1.4 ft, at Sun, Oct 25 11:00.
- Computed here, from the constants
- NOAA's own prediction
- Measured at the gauge, every six minutes
The last twelve hours as numbers
| Station time | Measured | Computed here | NOAA |
|---|---|---|---|
| Sun, Oct 25 02:00 | 4.10 ft | 2.87 ft | 2.85 ft |
| Sun, Oct 25 03:00 | 3.38 ft | 2.12 ft | 2.11 ft |
| Sun, Oct 25 04:00 | 2.93 ft | 1.76 ft | 1.76 ft |
| Sun, Oct 25 05:00 | 3.05 ft | 1.91 ft | 1.92 ft |
| Sun, Oct 25 06:00 | 3.72 ft | 2.57 ft | 2.60 ft |
| Sun, Oct 25 07:00 | 4.77 ft | 3.60 ft | 3.63 ft |
| Sun, Oct 25 08:00 | 5.92 ft | 4.74 ft | 4.78 ft |
| Sun, Oct 25 09:00 | 6.96 ft | 5.69 ft | 5.74 ft |
| Sun, Oct 25 10:00 | 7.52 ft | 6.20 ft | 6.25 ft |
| Sun, Oct 25 11:00 | 7.48 ft | 6.08 ft | 6.13 ft |
| Sun, Oct 25 12:00 | 6.72 ft | 5.33 ft | 5.38 ft |
| Sun, Oct 25 13:00 | 5.42 ft | 4.09 ft | 4.13 ft |
Measured heights from NOAA CO-OPS station 9415020, preliminary, above mean lower low water. The print carries the computed curve only: one year, no weather.