Surf Forecast
Issued by NWS Tiyan, Guam

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FZPQ50 PGUM 240431
SRFGUM

Surf Zone Forecast for the Mariana Islands
National Weather Service Tiyan GU
231 PM ChST Thu Jul 24 2025

.DISCUSSION...Tropical Depression 12W will bring hazardous surf
conditions across the Marianas. A high risk of rip currents along
east facing reefs will shift to west and south facing reefs tonight
into Friday and will likely continue through Saturday night. A
moderate risk of lighting will continue through the weekend into
next week.

$$

GUZ001-241945-
Guam-
231 PM ChST Thu Jul 24 2025

...HIGH RISK OF RIP CURRENTS THROUGH LATE TONIGHT ALONG EAST FACING
REEFS...

...HIGH RISK OF RIP CURRENTS FROM 6 PM THIS EVENING TO 6 AM CHST
SUNDAY ALONG SOUTH AND WEST FACING REEFS...

...HIGH SURF ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO 6 AM CHST
SUNDAY ALONG SOUTH AND WEST FACING REEFS...

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

.TONIGHT...
Rip Current Risk.....High *.
Surf Height
      North facing reefs............4 to 6 feet.
      East  facing reefs............7 to 9 feet.
      South facing reefs............8 to 10 feet.
      West  facing reefs............8 to 10 feet.
Swell/Period
      Primary swell................Southwest at 7 to 9 feet.
      Primary period...............8 to 9 seconds.
      Secondary swell..............East at around 3 feet.
      Secondary period.............9 seconds.
Water Temperature
      Ritidian buoy..........86 Degrees.
Winds...............Windy. Southwest at 25 to 30 mph.
                    Gusts to 40 mph.

.FRIDAY...
Rip Current Risk.....High. Pounding surf will produce life
                     threatening rip currents at reefs and beaches.
Surf Height
      North facing reefs............5 to 7 feet.
      East  facing reefs............5 to 7 feet.
      South facing reefs............7 to 9 feet.
      West  facing reefs............9 to 11 feet.
Swell/Period
      Primary swell................West to southwest at 7 to 9 feet.
      Primary period...............8 to 9 seconds.
      Secondary swell..............East at around 3 feet.
      Secondary period.............9 seconds.
Max Heat Index.........Around 94.
Winds...............Windy. Southwest at 25 to 30 mph.
                    Gusts to 40 mph.

.FRIDAY NIGHT...
Rip Current Risk.....High *.
Surf Height
      North facing reefs............6 to 8 feet.
      East  facing reefs............3 to 5 feet.
      South facing reefs............7 to 9 feet.
      West  facing reefs............8 to 10 feet.
Swell/Period
      Primary swell................West to southwest 6 to 8 feet.
      Primary period...............8 to 9 seconds.
      Secondary swell..............East at around 2 feet.
      Secondary period.............9 seconds.
Winds...............Windy. Southwest at 25 to 30 mph.
                    Gusts to 40 mph.


Tide information for the next 36 hours...

At Apra Harbor, Guam...
High tide  2.6 feet at  8:47 PM Thursday
Low  tide  1.8 feet at  1:54 AM Friday
High tide  2.7 feet at  6:44 AM Friday
Low  tide -0.4 feet at  2:13 PM Friday
High tide  2.6 feet at  9:24 PM Friday
Low  tide  1.7 feet at  2:42 AM Saturday
High tide  2.6 feet at  7:34 AM Saturday

$$
MPZ001>003-241945-
Rota-Tinian-Saipan-
231 PM ChST Thu Jul 24 2025

...TROPICAL STORM WATCH IN EFFECT...

...HIGH RISK OF RIP CURRENTS THROUGH LATE TONIGHT ALONG EAST FACING
REEFS...

...HIGH RISK OF RIP CURRENTS FROM 6 PM THIS EVENING TO 6 AM CHST
SUNDAY ALONG SOUTH AND WEST FACING REEFS...

...HIGH SURF ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO 6 AM CHST
SUNDAY ALONG SOUTH AND WEST FACING REEFS...

Tropical Depression 12W west-northwest of Guam will turn north-
northwest and pass west of the CNMI over the next couple of days,
bringing hazardous surf conditions to the region through Saturday
night. See the latest Typhoon Local Statement for specific
information for each island.


Tide information for the next 36 hours...

At Rota Island...
High tide  2.4 feet at  8:44 PM Thursday
Low  tide  1.7 feet at  1:48 AM Friday
High tide  2.5 feet at  6:41 AM Friday
Low  tide -0.4 feet at  2:07 PM Friday
High tide  2.4 feet at  9:21 PM Friday
Low  tide  1.6 feet at  2:36 AM Saturday
High tide  2.5 feet at  7:31 AM Saturday

At Tinian Island...
High tide  1.7 feet at  8:42 PM Thursday
Low  tide  1.5 feet at 12:53 AM Friday
High tide  2.0 feet at  5:42 AM Friday
Low  tide -0.5 feet at  1:45 PM Friday
High tide  1.7 feet at  9:18 PM Friday
Low  tide  1.4 feet at  1:52 AM Saturday
High tide  1.9 feet at  6:35 AM Saturday

At Tanapag Harbor, Saipan...
High tide  2.3 feet at  9:09 PM Thursday
Low  tide  1.7 feet at  2:05 AM Friday
High tide  2.2 feet at  6:37 AM Friday
Low  tide -0.6 feet at  2:20 PM Friday
High tide  2.3 feet at  9:47 PM Friday
Low  tide  1.6 feet at  3:00 AM Saturday
High tide  2.2 feet at  7:35 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.

$$