Apra Harbor, Guam tide times
The tide is rising: high tide at 4:24 AM, 2.0 ft. Measured 1.23 ft at 1:30 AM, 0.37 ft below the prediction.
Now
Today, Wednesday, September 23: every high and low tide, and the predicted curve through the day.
- High tide4:24 AM2.0 ft
- Low tide11:19 AM0.2 ft
- High tide6:24 PM2.2 ft
Feet above mean lower low water. Times are Chamorro Standard Time. Sunrise 6:11 AM, sunset 6:17 PM.
Alerts in force
National Weather Service products for coastal flooding, storm surge, high surf and tsunami at this station’s position.
None right now. The National Weather Service issues coastal flood advisories and warnings, storm surge watches and warnings, high surf advisories and tsunami messages for water at this station.
7-day tide table
Highest tide this week 2.5 ft, Mon, Sep 28 at 8:12 PM. Lowest 0.0 ft, Tue, Sep 29 at 2:54 AM.
| Date | High and low tides | Sunrise / sunset | Moon | |||
|---|---|---|---|---|---|---|
| Wed, Sep 23 Today | High 4:24 AM 2.0 ft | Low 11:19 AM 0.2 ft | High 6:24 PM 2.2 ft | 6:11 AM / 6:17 PM | Waxing gibbousRises 3:56 PM | |
| Thu, Sep 24 | Low 12:03 AM 1.2 ft | High 5:21 AM 2.1 ft | Low 12:00 PM 0.2 ft | High 6:46 PM 2.3 ft | 6:11 AM / 6:16 PM | Waxing gibbousRises 4:34 PM |
| Fri, Sep 25 | Low 12:35 AM 1.0 ft | High 6:11 AM 2.2 ft | Low 12:38 PM 0.3 ft | High 7:06 PM 2.4 ft | 6:11 AM / 6:16 PM | Waxing gibbousRises 5:12 PM |
| Sat, Sep 26 | Low 1:08 AM 0.8 ft | High 6:58 AM 2.3 ft | Low 1:15 PM 0.4 ft | High 7:26 PM 2.4 ft | 6:11 AM / 6:15 PM | Waxing gibbousRises 5:50 PM |
| Sun, Sep 27 | Low 1:41 AM 0.6 ft | High 7:44 AM 2.4 ft | Low 1:52 PM 0.6 ft | High 7:48 PM 2.5 ft | 6:11 AM / 6:14 PM | Full moon 2:49 AMRises 6:30 PM |
| Mon, Sep 28 | Low 2:16 AM 0.3 ft | High 8:33 AM 2.4 ft | Low 2:30 PM 0.9 ft | High 8:12 PM 2.5 ft | 6:11 AM / 6:14 PM | Waning gibbousRises 7:12 PM |
| Tue, Sep 29 | Low 2:54 AM 0.0 ft | High 9:25 AM 2.4 ft | Low 3:11 PM 1.1 ft | High 8:39 PM 2.4 ft | 6:11 AM / 6:13 PM | Waning gibbousRises 7:58 PM |
Next moon phases: full moon Sun, Sep 27, last quarter Sat, Oct 3.
Water level, last 48 hours
Measured 1.23 ft at 1:30 AM, 0.37 ft below the prediction. Highest in 48 hours: 1.89 ft at Tue 5:42 PM.
- Measured
- Predicted tide
Storm surge
Measured less predicted: −0.37 ft now; over 48 hours, −0.53 ft to −0.15 ft. Wind, air pressure and river flow move the water off the tide table.
Coastal flood thresholds
| Minor flooding | 3.3 ft |
| Moderate flooding | 5.0 ft |
| Major flooding | 6.3 ft |
The water is 2.11 ft below minor flood level now. Highest predicted tide in the next 7 days: 2.5 ft on Mon, Sep 28 at 8:12 PM, 0.9 ft below minor flooding. Thresholds are the National Ocean Service’s, in feet above MLLW.
Datums and records
Heights above mean lower low water (MLLW), the zero of this page and of NOAA’s charts. Tidal epoch 1983-2001.
| Mean higher high water MHHW | 2.34 ft |
| Mean high water MHW | 2.22 ft |
| Mean diurnal tide level DTL | 1.17 ft |
| Mean tide level MTL | 1.41 ft |
| Mean sea level MSL | 1.37 ft |
| Mean low water MLW | 0.60 ft |
| Mean lower low water MLLW | 0.00 ft |
| Highest water measured August 28, 1992 | 4.29 ft |
| Lowest water measured October 24, 1972 | -2.34 ft |
| Highest astronomical tide | 2.89 ft |
| Lowest astronomical tide | -1.26 ft |
Mean range of tide 1.62 ft; great diurnal range 2.34 ft.
What this means
Heights are feet above mean lower low water (MLLW): the average of the lower of each day’s two low tides over NOAA’s 19-year tidal epoch, and the zero of US tide tables and nautical charts. A low tide below that average is printed as a negative height.
Predictions are astronomical. They account for the moon and the sun, not the weather: onshore wind, low air pressure and high river flow hold the water above the prediction, offshore wind and high pressure hold it below. The water level above measures the difference.
Spring tides, the largest ranges of the month, follow the new and full moon by a day or two. Neap tides, the smallest, follow the quarter moons.
Nearby1
The closest other NOAA tide stations, nearest first.
More for this place
Sources
Tide predictions and water levels from NOAA’s Center for Operational Oceanographic Products and Services (CO-OPS). Coastal flood, storm surge and high surf products from the National Weather Service. Station 1630000: original at NOAA.