Coastal Flood Advisory

* WHAT...Dangerously large breaking waves up to 20 feet, decreasing to 10 to 15 feet tonight. 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...Super 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 this afternoon, especially along west- and south-facing shores. Then, surf will gradually diminish as Bavi moves farther away, which may warrant the High Surf Warning to be downgraded to an Advisory this afternoon.