Based on information received from the National Weather Service in Tiyan, Guam, a large north swell from a winter storm east of Japan will create hazardous surf along north and west facing reefs of the Marianas through today, Monday.
A high surf advisory is now in effect until 6pm today.
Surf will become hazardous 7 to 9 feet along north and west facing reefs of the Marianas this morning. Surf will remain near these heights most of the week. However, surf is gradually expected to shift toward the east facing reefs.
A small craft advisory remains in effect until 6pm Thursday.
Northeast winds will remain 20 to 25 knots through Monday night. Combined seas of 9 to 11 feet will build to between 10 and 13 feet around midweek. This will produce hazardous conditions for operators of small craft for the next several days.
The CNMI Homeland Security and Emergency Management is advising the general public and inexperienced mariners, especially those operating smaller vessels, to avoid boating in these conditions. If travel by boat is necessary exercise caution especially near reef lines and when entering or leaving harbors and inlets.
Meanwhile, a strong pressure gradient between a weak circulation to the south and a strong subtropical ridge to the north will maintain stronger than usual winds through the next few days. Strong winds are expected for the Marianas the next few days. A wind advisory is now in effect until 6pm Thursday.
Winds will build to between 20 and 30 mph with gusts to 40 mph by Monday, mainly during the daylight hours. Northeast winds will increase then build even more on Monday. Winds are expected to last through at least Thursday.
Winds of around 30 mph can cause minor damage and blow away small loose items.
The public is advised to take precautionary actions. Winds this strong can make driving difficult, especially for high profile vehicles such as a truck with a shipping container on it. Use extra caution. Bring small loose items indoors. Take down canopies and awnings that are susceptible to wind damage.