Tropical Storm Warning

...TROPICAL STORM CHOI-WAN MOVING WEST-NORTHWEST AND AWAY FROM ANATAHAN...

.NEW INFORMATION... None.

.AREAS AFFECTED... This local statement provides information and recommended actions for people on Saipan, Tinian, Agrihan, Pagan and Alamagan in the Commonwealth of the Northern Marianas.

.WATCHES/WARNINGS... A Tropical Storm Warning remains in effect for Saipan, Tinian and their adjacent coastal waters, as well as Alamagan, Pagan, and Agrihan in the CNMI. A Typhoon Watch remains in effect for Alamagan, Pagan, and Agrihan in the CNMI.

A Typhoon Watch means that typhoon conditions, including winds of 74 mph or more, are possible within 48 hours. A Tropical Storm Warning means that tropical storm conditions are expected within 24 hours.

A Flood Watch remains in effect for Tinian and Saipan. Please listen closely for any Flash Flood Warnings that might be in effect for your area.

Please check the latest public and marine forecasts for detailed information about additional hazards.

.STORM INFORMATION... At 7 AM ChST, the center of Tropical Storm Choi-wan (26W) was located near latitude 17.0N and longitude 144.9E. This was about 140 miles north-northwest of Saipan. Storm motion was west-northwest, 285 degrees, at 9 mph. Storm intensity was 60 mph. It is expected to make a turn toward the north with a slight decrease in forward speed through Saturday as it moves nearly parallel to the Mariana chain once it becomes a typhoon sometime this afternoon.

.SITUATION OVERVIEW... Tropical Storm Choi-wan has recently passed Anatahan, with the center around 70 miles to the northwest. Choi-Wan is expected to slow slightly as it continues westward, gradually turning to the north- northeast late tonight through Saturday. As Choi-wan pivots, the wind field will continue to expand, bringing other islands such as Guam and Rota under occasionally near-gale winds during peak conditions later this afternoon, as multiple rainbands continue to drag south. Meanwhile Saipan and Tinian may be under a lull in showers the next hour or two, intense convective lines will move in once again before noon, continuing stronger TS conditions for the weekend.

The most recent forecast track continues to indicate a movement along the axis of the far northern Marianas, prolonging the duration of damaging winds across the northern islands, likely maintaining damaging to destructive tropical storm conditions for a lengthy period of time continuing into Sunday afternoon. As Choi-wan is forecast to strengthen to a typhoon, there is a possibility for typhoon-force conditions to develop somewhere along the far northern Marianas. As such, a Typhoon Watch and Tropical Storm Warning remain in effect for Alamagan, Pagan, and Agrihan.