WESTERN PACIFIC Tropical Weather Update – November 9, 2026

Typhoon Cempaka Strengthens Over the Philippine Sea as Forecasters Monitor Its Changing Track

By Paul Harrison | Orbis Weather

Published: Monday, November 9, 2026

Coverage: Western North Pacific Ocean, Philippine Sea, South China Sea, Philippines, Taiwan, Japan, China, Guam and the Northern Mariana Islands.

🌏 Western Pacific Tropical Weather Overview

The Western Pacific remains active on Monday, November 9, 2026, with Typhoon Cempaka strengthening over the Philippine Sea while forecasters monitor an anticipated change in its direction.

Cempaka, designated Tropical Cyclone 31W by the Joint Typhoon Warning Center (JTWC), is the principal tropical cyclone currently being tracked across the western North Pacific.

The storm has developed into a significant typhoon, with powerful winds surrounding its center. Forecast guidance indicates that it could intensify further before turning eastward and gradually weakening later this week.

Meanwhile, the Philippines is experiencing additional weather hazards associated with the northeast monsoon, including strong coastal winds and dangerous marine conditions.

Today’s main developments:

• 🌀 Typhoon Cempaka: A powerful typhoon over the Philippine Sea, with further strengthening possible.

• 🇵🇭 Philippines: Cempaka has received the local name Samuel from PAGASA. Monsoon winds and rough seas remain important hazards.

• 🇯🇵 Japan: Forecasters are monitoring the typhoon’s anticipated eastward turn, although its eventual track remains uncertain.

• 🇹🇼 Taiwan: No direct impact from Cempaka is established in the available forecast information.

• 🌊 South China Sea: No additional organized tropical cyclone was identified in the latest basin-wide JTWC advisory reviewed.

• 🌦️ Additional development: No separate tropical disturbances were identified in that advisory.

The latest JTWC Significant Tropical Weather Advisory reviewed for this report was issued at 0600 UTC on November 9.

🌀 1. Typhoon Cempaka (31W) – Main Tropical Threat

Current storm information

At 0000 UTC on November 9, the JTWC placed Typhoon Cempaka near latitude 23.8°N and longitude 135.0°E, approximately 350 nautical miles west of Iwo To, Japan.

The storm was moving northwestward at approximately 11 knots during the preceding six hours.

JTWC storm analysis:

Important: JTWC uses one-minute sustained wind estimates, while the Japan Meteorological Agency (JMA) uses ten-minute averages. Their reported maximum wind speeds may therefore differ without indicating a contradiction.

Will Cempaka become stronger?

The Japan Meteorological Agency’s forecast indicates that Cempaka could reach maximum sustained winds of approximately 80 knots (92 mph / 148 km/h) by November 10.

The forecast also indicates a possible minimum central pressure near 960 hPa at peak intensity.

Environmental conditions may support additional strengthening in the short term. However, the storm is expected to encounter less favorable conditions later in the forecast period.

The predicted intensity is not guaranteed. Tropical cyclone intensity forecasts can change as new satellite observations and atmospheric data become available.

Where is Cempaka heading?

The forecast track suggests a change from the storm’s earlier northwestward movement toward an eastward or east-northeastward course.

JMA guidance indicates that the storm could begin turning during November 9 before accelerating eastward over the open Pacific.

If this forecast verifies, Cempaka would move away from the Philippines rather than approach the country’s main islands.

The storm’s precise turning point remains important. Small changes in the position and strength of surrounding atmospheric pressure systems can produce significant differences in a typhoon’s eventual path.

Expected development

These are forecast trends rather than confirmed future conditions.

🇵🇭 2. Philippines – Typhoon Samuel and Northeast Monsoon Hazards

PAGASA assigned Cempaka the Philippine name Samuel when the cyclone entered the Philippine Area of Responsibility.

In its November 9 bulletin issued at 5:00 p.m. Philippine time, PAGASA reported that Samuel had subsequently exited the Philippine Area of Responsibility.

The agency located the storm approximately 1,410 kilometers east-northeast of Extreme Northern Luzon, moving east-northeastward at around 10 km/h.

PAGASA reported maximum sustained winds of approximately 130 km/h, with gusts reaching 160 km/h.

Is the typhoon expected to strike the Philippines?

According to the November 9 PAGASA bulletin, Samuel was less likely to directly affect the country’s weather during the forecast period.

No Tropical Cyclone Wind Signal was in effect in that bulletin.

However, the absence of a direct typhoon threat does not mean the Philippines is free from dangerous weather.

The northeast monsoon continues to generate strong winds and hazardous sea conditions across numerous coastal areas.

Strong winds and rough seas

PAGASA identified the potential for strong to gale-force gusts across much of Luzon and the Visayas, together with several areas of Mindanao.

Marine conditions are particularly concerning along northern and western coastlines.

The agency’s 24-hour sea-condition outlook included:

PAGASA warned that sea travel could be dangerous, particularly for small vessels and motorbancas.

Residents and maritime operators should follow the latest local gale warnings, port advisories and instructions from Philippine authorities.

🇯🇵 3. Japan – Monitoring the Typhoon’s Recurvature

Japan’s meteorological authorities continue to monitor Cempaka as the storm moves across the western North Pacific.

The typhoon’s anticipated turn toward the east is particularly important for determining whether it remains over open water or approaches populated islands.

At the time of the forecast reviewed, the storm was situated well south of Japan’s main islands.

Potential hazards

Even when a tropical cyclone remains offshore, it can produce dangerous conditions over large areas of ocean.

Possible hazards include:

• Large ocean swells spreading beyond the immediate storm center.

• Dangerous winds and waves near the cyclone’s track.

• Disruption to shipping routes and offshore operations.

• Changing marine conditions as the typhoon accelerates.

The available forecast does not establish a direct landfall threat to mainland Japan.

Residents and marine operators should continue checking official JMA information as the track develops.

🇹🇼 4. Taiwan and the East China Sea

Taiwan and surrounding waters are important areas to monitor during the Western Pacific typhoon season.

However, Cempaka’s currently forecast eastward turn does not establish a direct threat to Taiwan.

Marine operators should nevertheless monitor updated forecasts because large tropical cyclones can generate swells well beyond their centers.

The Taiwan Central Weather Administration remains the appropriate source for official local marine forecasts, warnings and tropical cyclone information.

🇨🇳 5. China and the South China Sea

The latest JTWC basin-wide advisory reviewed for November 9 identified Cempaka as the only tropical cyclone in the western North Pacific.

No additional organized tropical disturbance was listed in the advisory.

This means that the advisory did not identify a separate tropical cyclone requiring tracking over the South China Sea at its issuance time.

However, thunderstorms, monsoon winds, locally heavy rainfall and rough coastal conditions can occur without a named tropical storm.

For southern China, including Guangdong, Hainan and surrounding coastal areas, local meteorological warnings remain important even during periods without an active nearby typhoon.

Regional outlook: No additional organized tropical cyclone was identified in the South China Sea in the JTWC advisory reviewed. This is not a guarantee that new development cannot occur later in the week.

🇬🇺 6. Guam and the Northern Mariana Islands

Guam, Rota, Tinian and Saipan remain important monitoring locations for tropical cyclones crossing the western North Pacific.

Cempaka’s analyzed position places its center well west of the Mariana Islands.

The current forecast does not establish a direct approach toward Guam or the Northern Mariana Islands.

However, tropical cyclone conditions can change rapidly, and marine forecasts should be monitored for swell and wind hazards.

The National Weather Service in Guam provides official forecasts and warnings for these islands.

🌊 7. Additional Tropical Development Across the Basin

The JTWC Significant Tropical Weather Advisory issued at 0600 UTC on November 9 reported:

Western North Pacific:

• One tropical cyclone: Typhoon Cempaka (31W).

• No additional tropical disturbances.

• No subtropical systems.

This assessment covers the conditions and disturbances identified in that particular advisory.

It does not rule out the possibility of additional development after the advisory was issued.

What conditions support tropical cyclone formation?

Western Pacific tropical cyclones generally require several atmospheric and oceanic ingredients:

Warm ocean water: Warm sea surfaces provide energy through evaporation and the release of latent heat.

Moist atmospheric conditions: Deep moisture helps maintain organized thunderstorm activity.

Low vertical wind shear: Relatively weak differences in wind speed and direction with height allow developing thunderstorms to remain organized around a circulation.

Pre-existing circulation: Tropical disturbances or low-pressure areas can provide the initial rotation necessary for development.

Favorable upper-level winds: Efficient outflow near the top of a developing cyclone can support strengthening.

Not every tropical disturbance develops into a tropical depression, and even favorable environmental conditions do not guarantee cyclone formation.

📅 8. Western Pacific Tropical Outlook: November 9–15, 2026

The main forecast concern for the coming week is the evolution of Typhoon Cempaka.

Forecast confidence: Moderate for the general expectation that Cempaka will turn eastward and weaken later in the week. Lower for its exact position, intensity and timing several days ahead.

No reliable numerical probability of additional tropical cyclone formation across the entire basin is established by the information reviewed for this report.

⚠️ 9. Tropical Weather Risk Assessment

These assessments describe the hazards identified in the available advisories. They are not substitutes for official warning classifications or location-specific emergency instructions.

🔬 10. Understanding the Difference Between JMA, JTWC and PAGASA

Western Pacific tropical cyclone reports can sometimes appear inconsistent because different meteorological agencies use different methods and geographical responsibilities.

Japan Meteorological Agency (JMA)

JMA serves as the Regional Specialized Meteorological Centre for tropical cyclones in the western North Pacific.

It provides international storm names, tropical cyclone analyses and forecasts using ten-minute sustained wind estimates.

Joint Typhoon Warning Center (JTWC)

JTWC provides tropical cyclone warnings and forecasts, primarily supporting U.S. military operations and other users.

It uses one-minute sustained wind estimates and identifies systems using designations such as 31W.

PAGASA

The Philippine Atmospheric, Geophysical and Astronomical Services Administration issues official tropical cyclone bulletins, warnings and local storm names for systems affecting or entering the Philippine Area of Responsibility.

Cempaka and Samuel refer to the same tropical cyclone.

Differences in reported wind speeds, storm positions and classifications can result from different observation times and operational methods.

For public safety decisions, residents should prioritize warnings issued by the meteorological authority responsible for their location.

🛟 11. Tropical Cyclone Safety and Preparedness

Tropical cyclones can create hazardous conditions even when their centers remain offshore.

People living or working in potentially affected coastal areas should:

• Monitor official tropical cyclone bulletins and local weather warnings.

• Avoid unnecessary marine travel when gale warnings or dangerous sea conditions are in effect.

• Secure loose outdoor equipment when strong winds are forecast.

• Prepare emergency supplies, including drinking water, medications, flashlights and charged communication devices.

• Follow evacuation or shelter instructions issued by local authorities.

• Avoid flooded roads and coastal areas exposed to dangerous surf.

• Remember that a forecast track can change and that hazards may extend outside the forecast cone.

For maritime operators, wave height, swell direction, wind strength and visibility can be as important as a cyclone’s forecast track.

📡 12. Official Tropical Weather Sources and Data Methodology

Orbis Weather prepares its tropical weather coverage using meteorological information from recognized forecasting agencies and supporting weather data providers.

Primary official sources

Japan Meteorological Agency (JMA)
https://www.jma.go.jp/jma/en/Activities/tropical.html

Official Western North Pacific tropical cyclone analyses, warnings and forecasts.

Joint Typhoon Warning Center (JTWC)
https://www.metoc.navy.mil/jtwc/jtwc.html

Tropical cyclone warnings, track forecasts and basin-wide significant tropical weather advisories.

PAGASA – Philippines
https://www.pagasa.dost.gov.ph/

Official Philippine tropical cyclone bulletins, monsoon forecasts, rainfall advisories and marine warnings.

National Weather Service Guam
https://www.weather.gov/gum/

Official forecasts and warnings for Guam and the Northern Mariana Islands.

Taiwan Central Weather Administration
https://www.cwa.gov.tw/eng/

Official Taiwanese weather and tropical cyclone information.

Supporting information

Weathernews
https://sea.weathernews.com/

Regional tropical cyclone reporting and interpretation of JMA forecasts.

UCAR Tropical Cyclone Guidance Project
https://verif.rap.ucar.edu/jntweb/hurricanes-beta/realtime/

Numerical tropical cyclone forecast guidance and supporting model information.

Editorial methodology

This article combines available official meteorological advisories with independent explanations of tropical cyclone development, forecast uncertainty and potential regional impacts.

Storm positions, wind speeds and forecast changes are attributed to their reporting agencies wherever possible.

Forecast information is distinguished from observed conditions. Where no current official hazard confirmation is available, the report avoids assigning unsupported warning levels or predicting specific local impacts.

Weather information can change after publication. Readers should consult official meteorological agencies for the latest warnings and emergency instructions.

Data reference: JTWC advisory ABPW10 PGTW issued November 9, 2026, at 0600 UTC; JMA-based Cempaka forecast information; and PAGASA’s November 9 tropical cyclone bulletin.

📝 13. Editorial Independence, Accuracy and Corrections

Orbis Weather provides independent weather reporting, tropical cyclone analysis and educational explanations of natural hazards.

Our objective is to make complex meteorological information understandable while maintaining clear distinctions between verified observations, official forecasts and potential future risks.

Orbis Weather is not an official meteorological warning agency and does not issue government-authorized evacuation orders, tropical cyclone warnings or emergency instructions.

When official agencies revise storm information, forecasts may change substantially. Material factual errors identified in published coverage should be corrected promptly, with significant changes clearly explained.

Readers should always follow the latest advice from their national meteorological services and local emergency management authorities.

🌏 Final Outlook – Western Pacific, November 9, 2026

Typhoon Cempaka is the Western Pacific’s principal tropical cyclone concern as the new week begins.

The storm has reached typhoon intensity over the Philippine Sea, and further strengthening remains possible before its expected turn toward the east.

Although the forecast suggests Cempaka will move away from the Philippines, dangerous coastal conditions associated with the northeast monsoon remain a separate concern, particularly across northern Philippine waters.

Elsewhere across the basin, the latest JTWC advisory reviewed did not identify any additional tropical disturbances or subtropical systems.

The next several days will be important for confirming Cempaka’s peak intensity, eastward movement and eventual weakening.

Orbis Weather will continue following official tropical cyclone advisories and significant changes across the Western Pacific.

Written by Paul Harrison for Orbis Weather.

Orbis Weather – Tracking Our Changing Planet.

Weather information is provided for public awareness and education. Always consult official meteorological authorities for warnings and emergency decisions.