Hydrologic Outlook — Guam County, gu
The National Weather Service issues this alert when conditions in the area meet its criteria — check the details below for what to expect.
Current Status
⚠️ Active: Hydrologic Outlook
Hydrologic Outlook issued August 22 at 7:43PM ChST by NWS Tiyan GU
ESFGUM This Hydrologic Outlook is for Guam, Rota, Tinian, and Saipan. A potential tropical disturbance will likely develop in the area and bring periods of heavy rainfall to the Marianas with rainfall totals of 4 to 7 inches possible. Heavy showers will moisten soils throughout the event and increase potential for mudslides. Residents on the Marianas need to closely monitor this developing situation as flood watches, advisories and flash flood warnings could be issued later. If living near streams and rivers, prepare to move items away from stream and river banks. Make sure storm drains nearby are not clogged, especially If living at low-lying areas.
Effective August 22, 2026 at 5:43 AM ET · Expires August 23, 2026 at 5:45 AM ET
Event Details
Event Type
Hydrologic Outlook
Severity
unknown
Issued By
NWS Tiyan GU
Expires
August 23, 2026 at 5:45 AM ET
Last Checked
just now
Also In Effect For
This same Hydrologic Outlook also covers:
Other Active Alerts in gu
Flash Flood Warning
Flood Advisory
Get Hydrologic Outlook Alerts for Guam County
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Frequently Asked Questions
What does a Hydrologic Outlook mean for Guam County, gu?
The National Weather Service issues this alert when conditions in the area meet its criteria — check the details below for what to expect.
Is this Hydrologic Outlook currently active?
Yes — this alert is active as of our last check (just now). It's set to expire August 23, 2026 at 5:45 AM ET.
How do I get notified about Hydrologic Outlook alerts for Guam County?
Download StormCast free on Google Play and set Guam County, gu as one of your monitored locations. StormCast checks the NWS feed continuously and pushes alerts like this directly to your phone — even with the screen off.
What other areas does this alert cover?
This same Hydrologic Outlook is also in effect for Saipan County, Rota County, Tinian County.