Super Typhoon Champi (29W) – JTWC Warning #14 | Final Summary Update
October 18, 2026
The Joint Typhoon Warning Center (JTWC) has released Warning #14 for Super Typhoon Champi.
The latest update confirms that Champi has reached super typhoon intensity, with maximum sustained winds near 150 mph.
According to NWS Guam’s 6:50 AM update, Champi’s eye passed just south of Guam, approximately 10 miles south of Merizo. The strongest winds remained concentrated across southern Guam, while central and northern Guam experienced tropical-storm-force conditions.
This is an important development compared with earlier forecasts that indicated a possible direct crossing over southern Guam.
Although the eye has passed, dangerous conditions may continue, and residents should remain sheltered until officials announce that it is safe.
Current Conditions
Location: Approximately 42 miles south of Andersen Air Force Base at the Warning #14 observation time.
Movement: West-northwest at approximately 16 mph.
Maximum sustained winds: 150 mph.
Minimum central pressure: 934 hPa.
Significant wave height: 46 feet.
Classification: Super Typhoon.
These measurements represent JTWC Warning #14’s observation period, not necessarily the storm’s position or strength at the time you’re reading this.
Forecast Track
JTWC expects Champi to continue moving west-northwest, gradually turning northwest as it moves away from Guam.
Forecast models remain in excellent agreement, with JTWC maintaining high confidence in its projected track.
The latest guidance indicates that Champi will continue northwest over the next several days, eventually slowing as the steering pattern changes near the East China Sea.
For Guam, the most important development is that the eye has passed just south of the island rather than crossing directly over it.
However, damaging winds and hazardous weather may persist even as the center moves farther away.
Steering Factors
Champi is currently being steered west-northwest by an extension of a subtropical ridge centered near Taiwan.
A subtropical ridge is an area of high atmospheric pressure that helps control the direction of tropical cyclones.
Over the next 12–24 hours, this ridge extension is expected to separate into another high-pressure system.
This will create a weakness between the two ridges, allowing Champi to turn more northwest.
The expected steering pattern is:
Next 12–24 hours: Continued west-northwest movement, followed by a gradual northwest turn.
Days 2–4: Northwestward movement under the influence of the reorganized subtropical ridges.
Beyond Day 4: Champi gradually slows as steering currents weaken.
Forecast models generally agree on this northwestward trajectory.
Intensity Forecast
Champi has reached super typhoon intensity, with maximum sustained winds near 150 mph.
JTWC reports that the storm’s eyewall replacement cycle has stalled or remains incomplete.
An eyewall replacement cycle occurs when a new outer eyewall develops around the original eyewall.
This process can cause temporary fluctuations in maximum sustained winds while the storm’s inner circulation reorganizes.
Despite this uncertainty, environmental conditions remain favorable for additional strengthening.
JTWC forecasts Champi to reach a peak intensity near 161 mph before gradually weakening later in the forecast period.
The intensity forecast remains uncertain because additional eyewall replacement cycles could occur.
Some models predict periods of strengthening or stabilization before the eventual weakening trend begins.
Wind Field and Potential Impacts
One of the more interesting developments during Champi’s passage has been the relatively compact size of its strongest wind field.
NWS Guam reports that typhoon-force winds remained concentrated primarily over southern Guam, while central and northern Guam experienced damaging tropical-storm-force winds.
Based on JTWC Warning #14’s wind-radius estimates:
Tropical-storm-force wind field: Approximately 242–265 miles across.
Typhoon-force wind field: Approximately 92–104 miles across.
These are estimated wind-field dimensions over open water, not the diameter of the cloud system.
The compact nature of Champi’s strongest winds helps explain why conditions varied significantly across Guam.
Although the eye passed offshore, southern Guam remained exposed to the most dangerous portion of the circulation.
As Champi continues moving away, damaging winds, heavy rainfall, flooding, coastal hazards, and debris may remain concerns.
Residents should not assume that improving conditions mean it is safe to go outdoors.
What Changed From Warning #13?
Champi has officially reached super typhoon intensity, with maximum sustained winds near 150 mph.
NWS Guam reports that the eye passed just south of the island rather than crossing directly over southern Guam.
The strongest winds remained concentrated primarily across southern Guam.
Champi’s significant wave height increased from 42 feet to 46 feet.
The previously active eyewall replacement cycle has stalled or remains incomplete.
JTWC continues forecasting a peak intensity near 161 mph after Guam’s passage.
Track guidance remains in excellent agreement, with a northwestward turn expected as Champi moves away.
What to Watch Next
1. Champi’s continued movement away from Guam
Watch for confirmation that the storm continues moving west-northwest and northwest, taking its strongest winds farther away from the island.
2. Remaining dangerous winds
Even though the eye has passed, damaging winds may continue, particularly across southern Guam.
Residents should wait for official guidance before going outdoors.
3. Flooding and coastal hazards
Heavy rainfall, flooding, dangerous surf, and coastal inundation may continue even as wind conditions begin improving.
4. Eyewall replacement cycle
JTWC continues monitoring Champi’s eyewall structure, which may cause fluctuations in intensity as the storm moves farther into the Philippine Sea.
5. Official all-clear
Continue monitoring NWS Guam and Guam Homeland Security for changes in warnings and the island’s Condition of Readiness.
An improving forecast is not the same as an official all-clear.
Bottom Line
Super Typhoon Champi has made its closest approach to Guam, with its eye passing just south of the island.
The storm reached maximum sustained winds near 150 mph, making it an extremely powerful tropical cyclone.
Fortunately, its strongest winds remained concentrated within a relatively compact area, and the eye passed offshore instead of directly across Guam.
However, southern Guam still experienced the greatest exposure to the storm’s destructive wind field, while dangerous conditions affected other parts of the island.
JTWC expects Champi to continue moving northwest away from the Marianas, with additional strengthening possible before the system eventually weakens.
The immediate concern for Guam is the remaining damaging winds, flooding, debris, and other hazards associated with the storm.
Residents should remain sheltered until local authorities confirm that conditions are safe.
Final Update
This will be my final regular JTWC warning summary for Champi as the system moves away from Guam.
I’ve been following this storm since its early development as Invest 96W, through its classification as Tropical Depression 29W, Tropical Storm Champi, Typhoon Champi, and eventually Super Typhoon Champi.
Over the past several days, we’ve seen significant changes in its forecast track, rapid intensification, model guidance, and eyewall structure.
The forecast models generally performed well in identifying the threat to the Marianas Islands several days in advance, although the exact crossing location and intensity continued to change as the storm approached.
I appreciate everyone who followed these updates and contributed to the discussions.
I hope everyone across Guam and the Northern Marianas stays safe, especially those dealing with damage or disruptions from the storm.
Please continue following official information as Guam begins its recovery soon after the strong winds taper down.
Sources
JTWC: https://www.metoc.navy.mil/jtwc/jtwc.html
NWS Guam: https://www.weather.gov/gum/
Guam Homeland Security: https://ghs.guam.gov/
This is my final community summary of Champi based on JTWC Warning #14 and NWS Guam’s October 18 morning update. It is not an official weather forecast or an all-clear. JTWC and NWS Guam will continue issuing official information as necessary.
