310
FZPQ50 PGUM 160720
SRFGUM

Surf Zone Forecast for the Mariana Islands
National Weather Service Tiyan GU
520 PM ChST Thu Oct 16 2025

.DISCUSSION...
There will be a moderate risk of rip currents along north and east
facing reefs through at least Friday night. Surf is expected to
diminish about a foot along all reefs this weekend as the north
swell briefly diminishes. A moderate risk of lightning is expected
tonight and then again this weekend as weak troughs move through
the region.

$$

GUZ001-MPZ001>003-162230-
Guam-Rota-Tinian-Saipan-
520 PM ChST Thu Oct 16 2025

36 hour Surf Zone Forecast for the Marianas from 600 PM Thursday
through 600 AM Saturday

.TONIGHT...
Rip Current Risk.....Moderate *.
Surf Height
      North facing reefs............5 to 7 feet.
      East  facing reefs............4 to 6 feet.
      South facing reefs............2 to 4 feet.
      West  facing reefs............1 to 3 feet.
Swell/Period
      Primary swell................North at 3 to 4 feet.
      Primary period...............12 seconds.
      Secondary swell..............East at 2 to 3 feet.
      Secondary period.............8 seconds.
Water Temperature
      Ritidian buoy..........86 Degrees.
Winds...............East at 10 to 15 mph.

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

.FRIDAY NIGHT...
Rip Current Risk.....Moderate *.
Surf Height
      North facing reefs............5 to 7 feet.
      East  facing reefs............5 to 7 feet.
      South facing reefs............2 to 4 feet.
      West  facing reefs............1 to 3 feet.
Swell/Period
      Primary swell................East at 3 to 4 feet.
      Primary period...............8 seconds.
      Secondary swell..............North at 3 to 4 feet.
      Secondary period.............11 seconds.
Winds...............East at 10 to 15 mph.


Tide information for the next 36 hours...

At Apra Harbor, Guam...
Low  tide  1.1 feet at 11:05 PM Thursday
High tide  1.8 feet at  4:04 AM Friday
Low  tide  0.2 feet at 10:46 AM Friday
High tide  2.3 feet at  5:43 PM Friday
Low  tide  0.9 feet at 11:49 PM Friday
High tide  1.9 feet at  5:17 AM Saturday

At Rota Island...
Low  tide  1.1 feet at 10:59 PM Thursday
High tide  1.7 feet at  4:01 AM Friday
Low  tide  0.2 feet at 10:40 AM Friday
High tide  2.1 feet at  5:40 PM Friday
Low  tide  0.8 feet at 11:43 PM Friday
High tide  1.8 feet at  5:14 AM Saturday

At Tinian Island...
Low  tide  0.9 feet at 10:15 PM Thursday
High tide  1.3 feet at  2:48 AM Friday
Low  tide  0.0 feet at 10:06 AM Friday
High tide  1.5 feet at  5:07 PM Friday
Low  tide  0.7 feet at 11:04 PM Friday
High tide  1.3 feet at  4:10 AM Saturday

At Tanapag Harbor, Saipan...
Low  tide  1.1 feet at 11:07 PM Thursday
High tide  1.7 feet at  4:16 AM Friday
Low  tide  0.3 feet at 10:49 AM Friday
High tide  2.1 feet at  5:47 PM Friday
Low  tide  0.9 feet at 11:46 PM Friday
High tide  1.8 feet at  5:27 AM Saturday

* 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.

$$