HIGH SURF ADVISORY  

Guam, GU

High Surf Advisory issued April 11 at 3:57AM ChST until April 16 at 6:00PM ChST by NWS Tiyan GU

HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM CHST THURSDAY... ...HIGH RIP CURRENT RISK NOW IN EFFECT THROUGH THURSDAY AFTERNOON

Areas Affected: Guam; Rota; Tinian; Saipan

Urgency: Expected

Severity: Minor

Certainty: Likely

Alert Sent: Saturday 3:57am ChST

Alert Effective: Saturday 3:57am ChST

Alert Expires: Saturday 6:00pm ChST (expect updated alert by this time)

Event Onset: Saturday 3:57am ChST

Event Ends: Thursday 6:00pm ChST

Issued by: NWS Tiyan GU

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM CHST THURSDAY... ...HIGH RIP CURRENT RISK NOW IN EFFECT THROUGH THURSDAY AFTERNOON...

* WHAT...Large breaking waves of 8 to 12 feet and dangerous rip
currents.

* WHERE...North and east facing reefs of the Marianas.

* WHEN...For the High Surf Advisory, until 6 PM ChST Thursday.
For the High Rip Current Risk, through Thursday afternoon.

* IMPACTS...Dangerous swimming and surfing conditions and
localized beach erosion. Rip currents can sweep even the best
swimmers away from shore into deeper water.

* ADDITIONAL DETAILS...Strong to near-gale trade winds, enhanced by
TS Sinlaku, are producing an east swell near 10 feet. This will
produce hazardous surf of 8 to 10 feet along north facing reefs
and 10 to 12 feet along east facing reefs. Surf is expected to
continue to build through Sunday, with dangerous surf likely by
Sunday afternoon.

Rip currents will be life threatening. Inexperienced swimmers
should remain out of the water due to dangerous surf conditions.
If caught in a rip current, relax and float. Don't swim against
the current. If able, swim in a direction following the
shoreline. If unable to escape, face the shore and call or wave
for help.

ID: urn:oid:2.49.0.1.840.0.0431c069a106a22307fec1d20e05a6e20268405d.001.1
Codes: GUZ001, MPZ001, MPZ002, MPZ003
Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.0431c069a106a22307fec1d20e05a6e20268405d.001.1

    RIP CURRENT STATEMENT  

Guam, GU

Rip Current Statement issued April 11 at 3:57AM ChST until April 16 at 6:00PM ChST by NWS Tiyan GU

HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM CHST THURSDAY... ...HIGH RIP CURRENT RISK NOW IN EFFECT THROUGH THURSDAY AFTERNOON

Areas Affected: Guam; Rota; Tinian; Saipan

Urgency: Expected

Severity: Moderate

Certainty: Likely

Alert Sent: Saturday 3:57am ChST

Alert Effective: Saturday 3:57am ChST

Alert Expires: Saturday 6:00pm ChST (expect updated alert by this time)

Event Onset: Saturday 3:57am ChST

Event Ends: Thursday 6:00pm ChST

Issued by: NWS Tiyan GU

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM CHST THURSDAY... ...HIGH RIP CURRENT RISK NOW IN EFFECT THROUGH THURSDAY AFTERNOON...

* WHAT...Large breaking waves of 8 to 12 feet and dangerous rip
currents.

* WHERE...North and east facing reefs of the Marianas.

* WHEN...For the High Surf Advisory, until 6 PM ChST Thursday.
For the High Rip Current Risk, through Thursday afternoon.

* IMPACTS...Dangerous swimming and surfing conditions and
localized beach erosion. Rip currents can sweep even the best
swimmers away from shore into deeper water.

* ADDITIONAL DETAILS...Strong to near-gale trade winds, enhanced by
TS Sinlaku, are producing an east swell near 10 feet. This will
produce hazardous surf of 8 to 10 feet along north facing reefs
and 10 to 12 feet along east facing reefs. Surf is expected to
continue to build through Sunday, with dangerous surf likely by
Sunday afternoon.

Rip currents will be life threatening. Inexperienced swimmers
should remain out of the water due to dangerous surf conditions.
If caught in a rip current, relax and float. Don't swim against
the current. If able, swim in a direction following the
shoreline. If unable to escape, face the shore and call or wave
for help.

ID: urn:oid:2.49.0.1.840.0.0431c069a106a22307fec1d20e05a6e20268405d.001.2
Codes: GUZ001, MPZ001, MPZ002, MPZ003
Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.0431c069a106a22307fec1d20e05a6e20268405d.001.2

    FLOOD WATCH  

Guam, GU

Flood Watch issued April 11 at 8:05AM ChST until April 15 at 10:00AM ChST by NWS Tiyan GU

FLOOD WATCH IN EFFECT FROM SUNDAY EVENING THROUGH WEDNESDAY MORNING

Areas Affected: Guam; Rota; Tinian; Saipan

Urgency: Future

Severity: Severe

Certainty: Possible

Alert Sent: Saturday 8:05am ChST

Alert Effective: Saturday 8:05am ChST

Alert Expires: Saturday 6:00pm ChST (expect updated alert by this time)

Event Onset: Sunday 6:00pm ChST

Event Ends: Wednesday 10:00am ChST

Issued by: NWS Tiyan GU

...FLOOD WATCH IN EFFECT FROM SUNDAY EVENING THROUGH WEDNESDAY MORNING...

* WHAT...Flash flooding caused by excessive rainfall is possible.

* WHERE...Guam, Rota, Tinian and Saipan.

* WHEN...From Sunday evening through Wednesday morning.

* IMPACTS...Excessive runoff may result in flooding of rivers,
creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
- Tropical Storm Sinlaku is slowly approaching the Marianas and
is expected to strengthen, possibly crossing Guam as a
typhoon possibly as early as Monday morning.

This is expected to produce 15 to 20 inches of rainfall
between Sunday night and Wednesday for Guam and Rota, with 8
to 15 inches expected for Tinian and Saipan. Widespread
showers, torrential rain and scattered thunderstorms are
expected as Sinlaku moves through the Marianas Monday through
Wednesday morning.

As showers are likely to persist, consistent rainfall is
likely to
produce flash floods and saturate the soils enough to
increase the
chance for mudslides over central to southern Guam.
- http://www.weather.gov/safety/flood

Residents of the Marianas need to closely monitor this developing
situation as flash flood warnings will likely be issued later.

If living near streams and rivers, move items away from stream and
river banks. Make sure storm drains nearby are not clogged,
especially If living at low-lying areas.

ID: urn:oid:2.49.0.1.840.0.6c5c6c7685a2973cfd841c565f7b1cba8e9817e9.001.1
Codes: GUZ001, MPZ001, MPZ002, MPZ003
Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.6c5c6c7685a2973cfd841c565f7b1cba8e9817e9.001.1

    SPECIAL WEATHER STATEMENT  

Guam, GU

Special Weather Statement issued April 10 at 7:10PM ChST by NWS Tiyan GU

Areas Affected: Guam; Rota; Tinian; Saipan

Urgency: Expected

Severity: Moderate

Certainty: Observed

Alert Sent: Friday 7:10pm ChST

Alert Effective: Friday 7:10pm ChST

Alert Expires: Saturday 8:15pm ChST

Event Onset: Friday 7:10pm ChST

Issued by: NWS Tiyan GU

Tropical Storm Sinlaku (04W) continues to organize north-northwest of
Chuuk. This system is currently moving very slowly in a west to
northwest direction, and this trend is expected to continue for
another roughly another 24 to 36 hours, before increasing slightly
in forward speed. TS Sinlaku is expected to strengthen as it
approaches the Marianas, possibly crossing Guam as a category 3
typhoon. Models continue to show a slight spread where TS Sinlaku's
track could shift slightly north or south, though these ranges are
narrowing and will continue to narrow over the next 12-24 hours.

A breezy, but relatively dry trade-wind pattern is in place over the
Marianas tonight, but as Tropical Storm Sinlaku closes in, winds are
expected to increase with conditions deteriorating sometime late
Sunday. The Marianas should make preparations for the potential for
Tropical Storm to Typhoon-Force winds, with the most likely time of
Tropical Storm-Force winds around Monday. For the far northern
Mariana Islands, breezy and choppy sea conditions are expected late
this weekend and into early next week, with potential for Tropical
Storm-Force winds around Tuesday.

This is expected to produce 15 to 20 inches of rainfall between
Sunday night and Wednesday for Guam and Rota, with 8 to 15 inches
expected for Tinian and Saipan. Widespread showers, torrential rain
and scattered thunderstorms are expected as Sinlaku moves through
the Marianas Tuesday through Tuesday night. As showers are likely to
persist, consistent rainfall is likely to produce flash floods and
saturate the soils enough to increase the chance for mudslides over
central to southern Guam.

ID: urn:oid:2.49.0.1.840.0.9b21cf6191a6bf267be7d1413bc00a7d7c2badf5.001.1
Codes: GUZ001, MPZ001, MPZ002, MPZ003
Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.9b21cf6191a6bf267be7d1413bc00a7d7c2badf5.001.1

    SPECIAL WEATHER STATEMENT  

Guam, GU

Special Weather Statement issued April 10 at 11:29AM ChST by NWS Tiyan GU

Areas Affected: Guam; Rota; Tinian; Saipan

Urgency: Expected

Severity: Moderate

Certainty: Observed

Alert Sent: Friday 11:29am ChST

Alert Effective: Friday 11:29am ChST

Alert Expires: Saturday 11:30am ChST

Event Onset: Friday 11:29am ChST

Issued by: NWS Tiyan GU

Tropical Storm Sinlaku (04W) continues to organize north-northwest of
Chuuk. This system will continue to move very slowly in a west to
northwest direction for another 24 to 36 hours, before increasing
forward speed as it strengthens. The current forecasts have the
system strengthening into a typhoon or stronger, and approaching the
Marianas. The potential track takes TS Sinlaku into the Marianas,
near Guam. However, models continue to show a slight spread where TS
Sinlaku's track could shift slightly north or south, though these
ranges are narrowing and will continue to narrow over the next 12-24
hours.

A breezy, but relatively dry trade-wind pattern is in place over the
Marianas, but as Tropical Storm Sinlaku closes in, conditions will
deteriorate sometime around late Sunday. The Marianas should make
preparations for the potential for Tropical Storm or Typhoon-Force
winds, with the most likely time of Tropical Storm-Forced winds
around Monday. For the far northern Mariana Islands, breezy and
choppy sea conditions are expected late this weekend and inter early
next week, with potential for Tropical Storm-Force winds around
Tuesday.

Locally heavy rainfall is likely with Tropical Storm Sinlaku.
Models show the potential 10 to 15 inches near the center of TS
Sinlaku, but if any of the islands will see this rainfall will
depend on exact track of TS Sinlaku. Ensemble guidance shows broader
potential for 5-8 inches across Guam, and 3-5 inches for Rota,
Tinian, and Saipan, but higher rainfall totals may shift depending if
the track of Tropical Storm Sinlaku shifts southward or northward.
of rainfall to develop for Guam early next week

ID: urn:oid:2.49.0.1.840.0.d8782e47b004ccb10f6573fdb326474fdd8bf6b3.001.1
Codes: GUZ001, MPZ001, MPZ002, MPZ003
Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.d8782e47b004ccb10f6573fdb326474fdd8bf6b3.001.1