479
FZPQ50 PGUM 170721
SRFGUM

Surf Zone Forecast for the Mariana Islands
National Weather Service Tiyan GU
521 PM ChST Fri Oct 17 2025

.DISCUSSION...A moderate risk of rip currents is expected along west,
north, and east facing reefs of the Marianas through Saturday, before
becoming low along west facing reefs thereafter. Surf is expected to
remain elevated along north and east facing reefs until the middle of
next week, when various northerly swells and trade swell weaken.

$$

GUZ001-MPZ001>003-172000-
Guam-Rota-Tinian-Saipan-
521 PM ChST Fri Oct 17 2025

36 hour Surf Zone Forecast for the Marianas from 600 PM Friday
through 600 AM Sunday

.TONIGHT...
Rip Current Risk.....Moderate *.
Surf Height
      North facing reefs............5 to 7 feet.
      East  facing reefs............6 to 8 feet.
      South facing reefs............1 to 3 feet.
      West  facing reefs............3 to 5 feet.
Swell/Period
      Primary swell................East at 4 to 6 feet.
      Primary period...............8 seconds.
      Secondary swell..............North at 3 to 4 feet.
      Secondary period.............11 seconds.
Water Temperature
      Ritidian buoy..........86 Degrees.
Winds...............East at 10 to 15 mph.

.SATURDAY...
Rip Current Risk.....Moderate *.
Surf Height
      North facing reefs............5 to 7 feet.
      East  facing reefs............6 to 8 feet.
      South facing reefs............1 to 3 feet.
      West  facing reefs............3 to 5 feet.
Swell/Period
      Primary swell................East at 4 to 6 feet.
      Primary period...............9 seconds.
      Secondary swell..............North at 2 to 4 feet.
      Secondary period.............12 seconds.
Max Heat Index.........Around 103.
Winds...............East at 10 to 20 mph.

.SATURDAY NIGHT...
Rip Current Risk.....High *.
Surf Height
      North facing reefs............4 to 6 feet.
      East  facing reefs............5 to 7 feet.
      South facing reefs............1 to 2 feet.
      West  facing reefs............2 to 4 feet.
Swell/Period
      Primary swell................East at 4 to 6 feet.
      Primary period...............9 seconds.
      Secondary swell..............North at 2 to 3 feet.
      Secondary period.............12 seconds.
Winds...............East at 10 to 20 mph.

Tide information for the next 36 hours...

At Apra Harbor, Guam...
Low  tide  0.9 feet at 11:49 PM Friday
High tide  1.9 feet at  5:17 AM Saturday
Low  tide  0.4 feet at 11:36 AM Saturday
High tide  2.3 feet at  6:08 PM Saturday
Low  tide  0.6 feet at 12:26 AM Sunday
High tide  2.0 feet at  6:14 AM Sunday

At Rota Island...
Low  tide  0.8 feet at 11:43 PM Friday
High tide  1.8 feet at  5:14 AM Saturday
Low  tide  0.4 feet at 11:30 AM Saturday
High tide  2.1 feet at  6:05 PM Saturday
Low  tide  0.6 feet at 12:20 AM Sunday
High tide  1.9 feet at  6:11 AM Sunday

At Tinian Island...
Low  tide  0.7 feet at 11:04 PM Friday
High tide  1.3 feet at  4:10 AM Saturday
Low  tide  0.2 feet at 10:51 AM Saturday
High tide  1.5 feet at  5:30 PM Saturday
Low  tide  0.5 feet at 11:47 PM Saturday
High tide  1.3 feet at  5:22 AM Sunday

At Tanapag Harbor, Saipan...
Low  tide  0.9 feet at 11:46 PM Friday
High tide  1.8 feet at  5:27 AM Saturday
Low  tide  0.5 feet at 11:36 AM Saturday
High tide  2.1 feet at  6:13 PM Saturday
Low  tide  0.7 feet at 12:22 AM Sunday
High tide  1.9 feet at  6:25 AM Sunday

* Low Risk of rip currents - Strong currents can still occur near
jetties and reef channels. Always have a flotation device with you
in the water.

Moderate Risk of rip currents - Wave conditions support stronger or
more frequent rip currents. Always have a flotation device with you
in the water.

High Risk of rip currents - Large waves will produce strong rip
currents, especially along narrow reefs and beaches. Rip currents
will be life threatening. If caught in a rip current, swim parallel
to the beach rather than against the current.

$$