Active Weather Alerts
Special Weather Statement
Issued: 9:46 AM Jul. 23, 2025 – National Weather Service
...DEVELOPING TROPICAL SYSTEM AND TRAILING MONSOON SURGE TO IMPACT THE MARIANAS OVER THE COMING DAYS... ...HEAVY RAIN, STRONG WINDS, AND CHOPPY SEAS AND SURF POSSIBLE... The Joint Typhoon Warning Center has issued a Tropical Cyclone Formation Alert for Invest 98W, centered near 12.9N, 145.0E, meaning that 98W is expected to develop into a significant tropical cyclone (Tropical Depression) within 24 hours. As 98W pushes across the southern Marianas and then off to the north and west of the islands over the next couple of days, a strong southwest monsoon surge is expected to develop across the Marianas in its wake. Heavy rainfall and breezy to windy conditions are expected across the Marianas through Saturday with the passage of 98W and the ensuing monsoon surge. Rainfall amounts of 6 to 12 inches are possible across the region through Saturday night, with locally higher amounts also possible. With the expected prolonged and heavy rainfall over the coming days, there will be a growing concern for mudslides potential. A Flood Watch is in effect through Saturday night. Winds and seas will become hazardous to small craft, with winds 20 to 30 kt and gusts to 40 kt and seas 8 to 12 feet anticipated by Thursday night. A Small Craft Advisory is in currently in effect for Tinian and Saipan, and will begin for Guam and Rota beginning Thursday morning, continuing through Saturday night. Surf is expected to rise along east and south facing reefs first beginning Thursday, then transition to south and west facing reefs as 98W pushes to the northwest and the southwesterly monsoon intensifies in its wake. This will cause the surf and risk of rip currents to rise along south and west facing reefs as surf will exceed the 9 foot threshold. Surf and rip risk look to remain hazardous through much of the weekend. For more information on Invest 98W (TCFA), see bulletins issued by JTWC under WMO header WTPN21 PGTW. Residents across the Marianas should continue monitoring local weather forecasts from the National Weather Service in Guam, and for additional information from your local emergency management office. Visit weather.gov/gum for the latest weather information from the National Weather Service.
High Surf Advisory
Issued: 6:15 AM Jul. 23, 2025 – National Weather Service
...HIGH RIP CURRENT RISK IN EFFECT FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT ALONG EAST FACING REEFS... ...HIGH SURF ADVISORY IN EFFECT FROM 6 PM THURSDAY TO 6 AM CHST SUNDAY ALONG SOUTH AND EAST FACING REEFS... ...HIGH RIP CURRENT RISK IN EFFECT FROM THURSDAY EVENING THROUGH LATE SATURDAY NIGHT ALONG SOUTH AND WEST FACING REEFS... * WHAT...For the High Surf Advisory, large breaking waves of 8 to 11 feet expected in the surf zone. For the High Rip Current Risk, dangerous rip currents expected. * WHERE...For the High Surf Advisory, south and west facing reefs. For the High Rip Current Risk, east, south and west facing reefs of the Marianas. * WHEN...For the High Surf Advisory, from 6 PM Thursday to 6 AM ChST Sunday. For the High Rip Current Risk, from Thursday morning through late Saturday night. * IMPACTS...Dangerous swimming and surfing conditions and localized beach erosion. Rip currents can sweep even the best swimmers away from shore into deeper water. * PRECAUTIONARY/PREPAREDNESS ACTIONS... Rip currents will be life threatening. Inexperienced swimmers should remain out of the water due to dangerous surf conditions. Rip currents will be life threatening. 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. &&
Rip Current Statement
Issued: 6:15 AM Jul. 23, 2025 – National Weather Service
...HIGH RIP CURRENT RISK IN EFFECT FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT ALONG EAST FACING REEFS... ...HIGH SURF ADVISORY IN EFFECT FROM 6 PM THURSDAY TO 6 AM CHST SUNDAY ALONG SOUTH AND EAST FACING REEFS... ...HIGH RIP CURRENT RISK IN EFFECT FROM THURSDAY EVENING THROUGH LATE SATURDAY NIGHT ALONG SOUTH AND WEST FACING REEFS... * WHAT...For the High Surf Advisory, large breaking waves of 8 to 11 feet expected in the surf zone. For the High Rip Current Risk, dangerous rip currents expected. * WHERE...For the High Surf Advisory, south and west facing reefs. For the High Rip Current Risk, east, south and west facing reefs of the Marianas. * WHEN...For the High Surf Advisory, from 6 PM Thursday to 6 AM ChST Sunday. For the High Rip Current Risk, from Thursday morning through late Saturday night. * IMPACTS...Dangerous swimming and surfing conditions and localized beach erosion. Rip currents can sweep even the best swimmers away from shore into deeper water. * PRECAUTIONARY/PREPAREDNESS ACTIONS... Rip currents will be life threatening. Inexperienced swimmers should remain out of the water due to dangerous surf conditions. Rip currents will be life threatening. 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. &&
Small Craft Advisory
Issued: 6:09 AM Jul. 23, 2025 – National Weather Service
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 6 AM CHST SUNDAY... * WHAT...East to southeast winds 15 to 25 kt becoming southwest 20 to 30 kt Thursday night with gusts up to 40 kt, and seas 8 to 12 feet expected. * WHERE...Tinian and Saipan Coastal Waters. * WHEN...Until 6 AM ChST Sunday. * IMPACTS...Conditions will be hazardous to small craft. * ADDITIONAL DETAILS...A passing tropical disturbance and a strong monsoon surge developing behind it will bring winds and seas hazardous to small craft. There is a potential for gale force winds to develop beginning Friday as the disturbance passes off slowly to the northwest and the southwest flow intensifies. PRECAUTIONARY/PREPAREDNESS ACTIONS... Inexperienced mariners, especially those operating smaller vessels, should avoid boating in hazardous conditions. &&
Flood Watch
Issued: 3:58 AM Jul. 23, 2025 – National Weather Service
...FLOOD WATCH NOW IN EFFECT THROUGH LATE SATURDAY NIGHT... * WHAT...Flash flooding caused by excessive rainfall continues to be possible. * WHERE...Guam, Rota, Tinian and Saipan. * WHEN...Through late Saturday night. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Flooding may occur in poor drainage and urban areas. Low-water crossings may be flooded. * ADDITIONAL DETAILS... - An unsettled pattern caused by a passing tropical disturbance Invest 98W and the monsoon surge in its wake is likely to produce heavy showers and thunderstorms, with a flash flooding risk to the region for at least the next several days. Total rainfall of 6 to 12 inches with locally higher amounts possible through Saturday night. - http://www.weather.gov/safety/flood PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop. &&
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