Flood Advisory in Effect for Southwestern Guam
Issued: September 9, 2026 — 2:26 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 Flood Advisory for southwestern Guam, in effect until 3:30 p.m. ChST this afternoon, Wednesday, September 9, 2026.
Current Status
Urban-area and small-stream flooding caused by excessive rainfall is expected. Minor flooding is expected in low-lying and poor drainage areas, with water over roadways possible and rises in small streams.
At 2:04 p.m. ChST, Doppler radar indicated heavy rain due to heavy showers and isolated thunderstorms, with additional showers moving toward the island. This may cause urban and small-stream flooding.
Locations that may experience flooding include Mangilao, Chalan Pago-Ordot, Yona, Hagåtña Heights, Talofofo, Mongmong-Toto-Maite, Sinajana, Inarajan, Asan, Merizo, Piti, Santa Rita, and Umatac.
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.