NWS / NOAA weather: Tropical Storm Warning issued October 1 at 3:27PM ChST by NWS Tiyan GU

...TROPICAL STORM CHOI-WAN MOVING WEST-NORTHWEST AND APPROACHING
ALAMAGAN FROM THE EAST-SOUTHEAST...

.NEW INFORMATION...
A Tropical Storm Warning has been issued for Agrihan in the CNMI.
A Typhoon Watch has been issued for Agrihan in the CNMI.

.AREAS AFFECTED...
This local statement provides important information and recommended
actions for people in the Northern Marianas.

.WATCHES/WARNINGS...
A Tropical Storm Warning has been issued for Agrihan in the CNMI.
A Typhoon Watch has been issued for Agrihan in the CNMI.
A Tropical Storm Warning remains in effect for Tinian, Saipan,
Alamagan and Pagan in the CNMI.
A Typhoon Watch remains in effect for Alamagan and Pagan in the CNMI.

A Tropical Storm Watch means that tropical storm conditions, including
winds of 39 to 73 mph, are possible within 48 hours.
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.

All persons in the Watch areas should review their preparedness plan
and begin to take actions to prepare for conditions as indicated by
your local forecast and additional details, below, for your island.

.STORM INFORMATION...
At 2 PM ChST, the center of Tropical Storm Choi-wan (26W) was located
near latitude 16.8N, longitude 147.5E. This was about 290 miles
northeast of Guam. Choi-wan is estimated to be moving west-northwest
at 18 mph, to then slow down to less than 10 mph tonight. The current
forecast speed is likely to be a result of a center position being
farther west than the prior forecast, skewing the forward speed higher
during this cycle. Storm intensity was 45 mph. Choi-wan is forecast
to intensify through tonight, possibly becoming a typhoon Friday
afternoon.

.SITUATION OVERVIEW...
Tropical Storm Choi-wan (26W) has increased in forward speed to then
once again slow down later tonight, with a slight contraction in the
tropical storm-force wind field expected to the west and southwest,
but remain well within Tinian, Saipan and their adjacent waters as
Choi-wan comes closer. As such, the Tropical Storm Watch was upgraded
to Tropical Storm Warning for Agrihan, and a new Typhoon Watch
issued as well. Choi-wan will continue west through tonight, making a
turn to the northwest Friday morning as it begins to approach
Alamagan from the south and intensify into a typhoon sometime Friday
afternoon, turning sharply northward, to then move north-
northeastward late Friday night. This forecasted passage 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 beginning this evening and continuing into
Sunday afternoon. As Choi-wan is forecast to strengthen to a typhoon,
there is likelihood 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 and Pagan.

Severity

Severe (4/5) · CAP Severe

This month

43rd Hurricane / cyclone alert at severity 4+ in the last 30 days