Tropical Storm Warning issued October 1 at 9:22PM ChST by NWS Tiyan

...TROPICAL STORM CHOI-WAN MOVING WEST INTO THE NORTHERN
MARIANAS, SOUTHEAST OF ALAMAGAN...

.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 Tinian, Saipan, and
adjacent coastal waters.

A Tropical Storm Warning remains in effect for 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 PM ChST, the center of Tropical Storm Choi-wan (26W) was
located near latitude 17.0N, longitude 146.4E. This was about 55
miles southeast of Alamagan, 90 miles south-southeast of Pagan,
and 260 miles north-northeast of Guam. Storm motion was west, 280
degrees, at 13 mph. Storm intensity was 45 mph.

.SITUATION OVERVIEW...
Tropical Storm Choi-Wan is expected to slow slightly as it
continues westward overnight, with the center passing to the south
of Alamagan early Friday morning. It is then expected to make a
turn toward the northwest, then north with a decrease in forward
speed through Friday. Then, Choi-wan looks to gradually turn to
the north-northeast on Saturday after it emerges west of the
northern islands. Choi-wan is forecast to intensify through
Friday, potentially becoming a typhoon late Friday night or early
Saturday morning.

This forecasted passage moving along the axis of the far northern
Marianas is still expected to prolong the duration of damaging
winds across the northern islands, likely leading to a lengthy
period of time of damaging to destructive tropical storm
conditions 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. The
latest forecast track has shifted Choi-Wan farther west of the
islands, slightly decreasing this possibility.