JIC Release No. 11 - Tropical Storm Mangkhut organizes, intensifies

JIC Release No. 11 - Tropical Storm Mangkhut organizes, intensifies

Tropical Storm Mangkhut continues to organize and intensify as it heads toward the Marianas. The National Weather Service (NWS), Guam Weather Forecast Office are continuing to monitor the storm. Currently, Guam remains in Condition of Readiness (COR 3), which means damaging winds of 39-57 mph are expected within 48 hours.

As of 4 a.m., Mangkhut was located at 14.9 degrees north latitude and 156.9 degrees east longitude, about 745 miles east of Saipan and 820 miles east of Guam, with maximum sustained winds of 50 mph.  

The tropical storm will continue its west-northwest track and is expected to intensify, becoming a typhoon later today or tonight, and possibly a Category 4 typhoon by the time it reaches Guam, on Tuesday as it makes its closest point of approach. It is important to still prepare for the worst-case-scenario of a Category 5 typhoon:

  • Category 4 Typhoon is referred to as a “Very Strong Typhoon” with maximum sustained winds of 130-156 and peak gusts of 165-198 mph.
  • Category 5 Typhoon is referred to as a “Devastating Typhoon” with maximum sustained winds of 157-194 mph and peak gusts of 199-264 mph. A Category 5 typhoon has the ability to be life-threatening to those that do not prepare in advance.

A typhoon watch is in effect for Guam, Rota, Tinian, and Saipan and adjacent coastal waters in the Marianas, meaning typhoon conditions, including destructive winds of 74 mph or more, are possible within 48 hours, by Mondayevening.

Winds will be between 69 and 104 mph close to the center of Mangkhut as it intensifies and reaches the Marianas waters. Winds are forecasted to begin to rise Monday afternoon, reach maximum Tuesday morning, and start to subside Tuesday evening. Further from the center will be tropical storm force winds.

Combined seas in excess of 30 feet are possible due to the expected high winds near the center. Farther from the center, combined seas will be between 10 and 20 feet elsewhere in the Marianas waters.

Use today to prepare and stay up to date. The Joint Information Center will provide important information throughout today, before the damaging winds arrive. Be on the lookout for the most up to date information, paying close attention to the date and time on posts or press releases.

How Can I Stay Up to Date with the Joint Information Center?

The Joint Information Center is the government of Guam, military and federal government’s clearinghouse for accurate information during emergencies. The following is a list of radio partners, where you can get updated information about Tropical Storm Mangkhut:

o KSTO 95.5 FM
o 102.9 KISH FM
o Isla 630 AM
o K57 AM
o I94 FM
o Power 98 FM
o Hit Radio 100 
o Cool FM
o The BOSS 104.3
o Star 101.1
o 101.9 KTKB 
o 105.1 KAT FM
o 99.5 The Shark
o KHMG 88.1 FM

TV and Newspaper partners include:
Visit the following links for the latest advisory information:
·           NWS Website: http://www.prh.noaa.gov/guam/
·           NWS Facebook: https://www.facebook.com/NWSGuam/
·           GHS/OCD Website: https://ghs.guam.gov/
·           GHS/OCD Facebook: https://www.facebook.com/GHSOCD/
·           Joint Region Marianas Facebook: https://www.facebook.com/jrmguam/
·           Governor Calvo Facebook: https://www.facebook.com/eddiebazacalvo/

For more information, contact the GHS/OCD 24/7 watch desk at (671) 475-9600 or (671) 482-7019 until 9 a.m. today, when alternate numbers will be provided.

We continue to urge residents to be prepared by Monday night as damaging winds of 39 mph or more are expected as early as that evening. Weather conditions may quickly change or even worsen.



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June 2018 is Typhoon Preparedness Month