WESTERN PACIFIC · 2009 SEASON
Typhoon Choi-Wan (2009)
Recorded track and intensity · 11 Sept 2009–20 Sept 2009
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Wind speed & pressure
15 Sep, 18:00 UTCForward speed & ACE
15 Sep, 18:00 UTCHover or tap either graph to follow the track. The slider controls both graphs. Each line uses its matching colored axis.
Forward speed measures the center’s motion. ACE accumulates squared one-minute winds at 00, 06, 12 and 18 UTC during tropical or subtropical stages at 34 kt or above. Missing measurements remain gaps.
161 mph / 259 km/h
15 Sept 2009 · tropical stage
Full archive record, including non-tropical stages if present
Along the recorded center positions
STORM HISTORY
Track and intensity summary
Choi-Wan is listed in the Western Pacific basin for the 2009 season. Its archived track begins on 11 Sept 2009, 12:00 UTC at 13.4°N, 155°E. The first observation lists sustained winds of 15 knots. These dates describe the available observations, which may include stages before and after the tropical cyclone phase.
The first Category 5 observation appears on 15 Sept 2009, 15:00 UTC. The highest recorded tropical-stage one-minute sustained wind is 140 knots (161 mph / 259 km/h), first recorded on 15 Sept 2009, 18:00 UTC at 18.2°N, 144.2°E. The minimum recorded tropical-stage central pressure is 918 hPa on 15 Sept 2009, 18:00 UTC.
The full record spans 222 hours and approximately 4,620 kilometers along the recorded center positions. The last recorded position is 38.8°N, 156.1°E on 20 Sept 2009, 18:00 UTC. The final tropical-stage observation is earlier, on 20 Sept 2009, 03:00 UTC.
This summary is calculated from the NOAA IBTrACS archive. Category 5 describes the storm’s peak recorded wind intensity, not its intensity at landfall or the severity of impacts at any location. Landfall times, damage and casualties have not been independently reviewed for this page.
METHODOLOGY
Data sources and limitations
The map and summary are generated from NOAA’s IBTrACS v04r01 archive. Wind and category use US-agency records; minimum pressure is calculated during the tropical stage, with the archive’s pressure source retained. Category 5 refers to the Saffir–Simpson one-minute wind scale; local agencies may use different classifications. Coastlines use Natural Earth’s 1:10m land data.
Track distance adds great-circle distances between consecutive observations, excluding gaps over 12 hours. This track has no gaps over 12 hours. The line shows the storm’s center, not its size, rainfall or flood extent. Converted wind speeds are rounded to the nearest whole unit.
Archive retrieved
NOAA IBTrACS archive · Field documentation
Sources & methodology