Coastal Flood Advisory

Updated to remove reef distinction, see additional details.

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 4 PM CHST THURSDAY... ...COASTAL FLOOD ADVISORY REMAINS IN EFFECT UNTIL 6 AM CHST WEDNESDAY...

* WHAT...Dangerously large breaking waves up to 20 feet, decreasing to 10 to 15 feet Thursday. Minor coastal flooding expected.

* WHERE...Guam, Rota, Tinian and Saipan.

* WHEN...For the High Surf Warning, until 4 PM ChST Thursday. For the Coastal Flood Advisory, until 6 AM ChST Wednesday.

* IMPACTS...Flooding of lots, parks, and roads with only isolated road closures expected. Breaking waves can sweep people off jetties and docks, and into dangerous seas. Life-threatening swimming conditions and significant beach erosion can be expected.

* ADDITIONAL DETAILS...Typhoon Bavi (09W) and the trailing monsoon surge will continue to produce significant swells towards the Marianas. Dangerous surf heights of up to 20 ft and coastal inundation of 1 to 3 ft can be expected through at least tonight, especially along west-facing shores. A local observer reports 15 to 18 ft at Oka point. Then, surf will gradually diminish as Bavi moves farther away. South and west facing shores are expected to see the highest surf. Huge waves are producing deadly rip currents through at least Wednesday night.