8:50 a.m. Heavy Rainfall Anticipated to Develop Around Midweek as Disturbance Approaches

The National Weather Service (NWS) Guam Weather Forecast Office continues to monitor Invest 99W, a weak circulation near 12N147E, southeast of Guam. It has been downgraded to sub-low by the Joint Typhoon Warning Center, reflecting a decreasing potential for this disturbance to become a significant tropical cyclone. The NWS notes computer models still point to a disturbance to eventually take shape to the south of Guam by midweek, that is anticipated to lift north or northwest, bringing increasing showers and winds to the Marianas as early as Tuesday.

Heavy showers and near gale-force (39 mph) winds remain possible with the peak anticipated around Wednesday or Thursday. There is potential for Guam and the CNMI to see rainfall amounts of 3 to 7 inches between Tuesday and Thursday night. This rainfall could result in minor flooding across the islands, with flash flooding possible in areas of heavier rainfall, especially over Guam.

Residents and visitors are advised to take the following precautionary actions:

Those living in flood-prone areas should take action; clear drainage areas and unblock storm drains to minimize flooding;
Stay up to date with the latest weather information;
When driving in heavy rain, be alert for low visibilities and slippery roads;
Slow down where water is ponding on the road;
Turn Around, Don’t Drown. Avoid walking or driving through flood waters. Just 6 inches of moving water can knock you down, and 2 feet of water can sweep your vehicle away;
Do not camp, park, or hike along streams and rivers. These areas can flood quickly and with little warning;
Be alert for possible landslides in areas of steep terrain. Be alert for hillsides or slopes that appear saturated or unstable. Look for warning signs such as cracks in the ground, leaning trees, or sudden changes in water flow. Report any signs of potential landslides to local authorities immediately.

The weather forecast for the week includes:

Today: Breezy. Partly sunny with isolated showers. East winds 15 to 20 mph. Highs near 87. Chance of showers 20 percent.
Tonight: Mostly cloudy with scattered showers and isolated thunderstorms. East winds 10 to 15 mph. Lows around 78. Chance of showers 50 percent.
Monday: Breezy. Partly sunny with scattered showers. East winds 20 to 25 mph. Highs around 86. Chance of showers 40 percent.
Monday Night and Tuesday: Breezy. Mostly cloudy. Scattered showers. East winds 15 to 25 mph. Lows around 78. Highs near 85. Chance of showers 40 percent.
Tuesday Night and Wednesday: Breezy. Mostly cloudy. A 40 percent chance of showers and a slight chance of thunderstorms. Lows in the upper 70s.
Wednesday Night: Mostly cloudy with a 50 percent chance of showers and a slight chance of thunderstorms. Lows in the upper 70s.
Thursday and Thursday Night: Cloudy with a 50 percent chance of showers and a slight chance of thunderstorms. Highs in the mid 80s. Lows in the upper 70s.

The Office of Homeland Security and the Office of Civil Defense (OHS-OCD) remind the community to stay alert for additional advisories in the coming days.

Visit the following links for the latest advisory information:

NWS Website: https://www.weather.gov/gum/
NWS Facebook: https://www.facebook.com/NWSGuam/
GHS/OCD Website: https://ghs.guam.gov/
GHS/OCD Facebook: https://www.facebook.com/GHSOCD/

For more information, contact Public Information Officer Jenna G. Blas at (671) 489-2540 or via email at jenna.g.blas@ghs.guam.gov.

X Flooding is a temporary overflowing of water onto land that is normally dry. Flooding may happen with only a few inches of water, or it may cover a house to the rooftop. There are many possible causes of floods including heavy rain, coastal storms and storm surge, waterway overflow from being blocked with debris, or overflow of levees, dams, or waste water systems. Flooding can occur slowly over many days or happen very quickly with little or no warning, called flash floods.

To learn more, visit https://www.ready.gov/floods

Wildfire

Regularly clean the roof and gutters.
Maintain an area approximately 30’ away from you home that is free of anything that will burn, such as wood piles, dried leaves, newspapers and other brush.
Connect garden hoses long enough to reach any area of the home and fill garbage cans, tubs, or other large containers with water.
Review your homeowner's insurance policy and also prepare/update a list of your home's contents.

Fire Weather

Turn on your TV/radio. You’ll get the latest weather updates and emergency instructions.
Know where to go. If you are ordered to evacuate, know the route to take and have plan of where you will go. Check-in with your friends and family.
Keep your car fueled, in good condition, and stocked with emergency supplies and a change of clothes.

Drought

Conserve water

Take shorter showers.

Turn off the water while brushing your teeth or shaving.
Run the washer less frequently and only when you have a full load.
Water your lawn less frequently and do so when the temperature is cooler in the early morning or late evening.
When you run the tap to heat or cool water, keep a pitcher to store the water and use it to water plants.
Avoid washing your car.

Practice fire prevention

Don't set off fireworks when conditions are dry.
Deposit cigarette butts in the proper receptacle to avoid starting a
Pour water over camp fires and backyard fire pits to ensure they are completely out before leaving them unattended.

Follow directions from local officials. If there are restrictions on water usage, be sure to heed them.

To learn more, visit https://www.ready.gov/wildfires and https://www.ready.gov/drought

X
Typhoons/Hurricanes are massive storm systems that form over the water and move toward land. Threats from typhoons/hurricanes include high winds, heavy rainfall, storm surge, coastal and inland flooding, and rip currents.

“Hurricanes” form in the Atlantic Northeast Pacific region and “Typhoons” form in the Northwest Pacific Region. These large storms are call cyclones in other parts of the world.

To learn more, visit https://www.ready.gov/hurricanes.