Flash Flood Warning in Effect for Central Guam
Issued: September 9, 2026 — 3:32 p.m. ChST
The Guam Homeland Security/Office of Civil Defense (GHS/OCD) advises residents that the National Weather Service (NWS) Tiyan has issued a Flash Flood Warning for central Guam, in effect until 4:30 p.m. ChST this afternoon, Wednesday, September 9, 2026. A Flood Advisory is also in effect for all of Guam until 5:30 p.m. ChST.
Current Status
At 3:02 p.m. ChST, Doppler radar indicated thunderstorms producing heavy rain across the warned area. Between 1.0 and 2.0 inches of rain have fallen, with additional rainfall amounts of 0.5 to 1.5 inches possible. Flash flooding is ongoing or expected to begin shortly.
Flash flooding is expected of small creeks and streams, urban areas, highways, and streets, as well as other poor drainage and low-lying areas.
Locations that will experience flash flooding include Mangilao, Chalan Pago-Ordot, Barrigada, Yona, Talofofo, Mongmong-Toto-Maite, Sinajana, and Santa Rita.
Island-wide, under the Flood Advisory, minor flooding is expected in low-lying and poor drainage areas, with water over roadways possible and rises in small streams.
What You Should Do Now
Residents and motorists are advised to take the following precautions:
- Do not drive through flooded roadways. Turn Around, Don't Drown. Most flood deaths occur in vehicles.
- Be aware of your surroundings and do not drive on flooded roads.
- Monitor official updates from NWS Tiyan and GHS/OCD for changing weather conditions.
GHS/OCD continues to monitor conditions in coordination with NWS Tiyan and will provide additional information as needed.
For the latest official weather information, visit the National Weather Service at weather.gov/gum. For preparedness information, visit ghs.guam.gov or contact the GHS/OCD at 475-9600.