Tropical Cyclone Bulletin #11

Typhoon "Jenny"

Issued at 05:00 am, 02 October 2023
(Valid for broadcast until the next advisory to be issued at 11:00 AM today)

  • Heavy Rainfall Outlook
  • Forecast accumulated rainfall for tomorrow
  • ·   50-100 mm: Batanes, Babuyan Islands, and the northern portion of mainland Cagayan.
  • Forecast accumulated rainfall for Wednesday
  • ·   100-200 mm: Batanes
  • ·   50-100 mm: Babuyan Islands, Ilocos Norte, and the northern portions of mainland Cagayan and Apayao.
  • Forecast rainfall are generally higher in elevated or mountainous areas. Under these conditions, flooding and rain-induced landslides are possible especially in areas that are highly or very highly susceptible to these hazards as identified in hazard maps and in localities that experienced considerable amounts of rainfall for the past several days.
  • In addition, JENNY will continue to enhance the Southwest Monsoon and bring occasional to monsoon rains over the western portions of Central Luzon, Southern Luzon, Visayas, and Mindanao in the next 3 days. For more information, refer to Weather Advisory No. 3 for Southwest Monsoon issued at 11:00 PM yesterday and 24-Hour Public Weather Forecast and Outlook at 4:00 AM today.
  • Severe Winds 
  • The wind signals warn the public of the general wind threat over an area due to the tropical cyclone. Local winds may be slightly stronger/enhanced in coastal and upland/mountainous areas exposed to winds. Winds are less strong in areas sheltered from the prevailing wind direction.
  • ·         Minimal to minor impacts from strong winds are possible within any of the areas under Wind Signal No. 1.
  • The most likely highest Wind Signal that will be hoisted is Wind Signal No. 2, although the potential for Wind Signal No. 3 is not ruled out at this time.
  • The enhancement of the Southwest Monsoon by JENNY will bring gusty conditions for the next 3 days over the following areas not under any Wind Signal, especially in coastal and upland/mountainous areas exposed to winds:
  • ·         Today: Most of MIMAROPA, Western Visayas, and Bicol Region
  • ·         Tomorrow: Metro Manila, CALABARZON, MIMAROPA, Bicol Region, and Western Visayas
  • ·         Wednesday: Bataan, the southern portion of Aurora, Metro Manila, CALABARZON, the northern portion of Palawan including Calamian Islands, Romblon, Occidental Mindoro, and portions of Bicol Region.
  • Under the influence of JENNY, a Gale Warning is in effect for the coastal waters of Batanes and Babuyan Islands. For more information refer to Gale Warning No. 1 issued at 5:00 AM today.
  • In addition, JENNY will bring moderate to rough seas (2.0 to 4.0 m) over the coastal waters of mainland Cagayan. Mariners of motor bancas and similarly-sized vessels are advised to take precautionary measures while venturing out to sea and, if possible, avoid navigating in these conditions, especially if inexperienced or operating ill-equipped vessels.
  • JENNY is forecast to move generally northwestward until tomorrow before turning west northwestward or westward thereafter. On the track forecast, JENNY will make landfall over the southern portion of Taiwan on Thursday afternoon or evening then exit the Philippine Area of Responsibility (PAR) over the Taiwan Strait between Thursday evening or Friday morning. A landfall or close approach scenario over the Batanes area is still not ruled out, although the likelihood is decreasing.
  • JENNY is forecast to steadily intensify throughout the forecast period and may reach its peak intensity tomorrow. A slightly weakening trend may begin by mid-Wednesday due to a potential for dry air entrainment and increased wind shear prior to landfall over Taiwan.
Location of Eye/center

The center of the eye of Typhoon JENNY was estimated based on all available data at 655 km East of Aparri, Cagayan or 665 km East of Calayan, Cagayan (18.9 °N, 127.8 °E )


Moving Northwestward at 10 km/h


Maximum sustained winds of 120 km/h near the center and gustiness of up to 150 km/h

Forecast Position
  • Oct 02, 2023 02:00 PM - 580 km East of Calayan, Cagayan
  • Oct 03, 2023 02:00 AM - 420 km East of Basco, Batanes
  • Oct 03, 2023 02:00 PM - 330 km East of Itbayat, Batanes
  • Oct 04, 2023 02:00 AM - 240 km East Northeast of Itbayat, Batanes
  • Oct 04, 2023 02:00 PM - 185 km North Northeast of Itbayat, Batanes
  • Oct 05, 2023 02:00 AM - 180 km North of Itbayat, Batanes
  • Oct 06, 2023 02:00 AM - 290 km Northwest of Itbayat, Batanes (OUTSIDE PAR)
  • Oct 07, 2023 02:00 AM - 390 km West Northwest of Itbayat, Batanes (OUTSIDE PAR)
Wind Signal (Areas with TCWS)
Tropical Cyclone Wind Signal no.
Affected Areas
  • Luzon
    • Batanes, Babuyan Islands, the eastern portion of mainland Cagayan (Santa Ana, Gonzaga, Buguey, Santa Teresita, Lal-Lo, Baggao, Gattaran, Peñablanca), and the eastern portion of Isabela (Maconacon, Divilacan, Palanan)
  • Visayas
    • -
  • Mindanao
    • -
Meteorological Condition
  • A tropical cyclone will affect the locality.
  • Winds of 39-61 km/h may be expected in at least 36 hours or intermittent rains may be expected within 36 hours. (When the tropical cyclone develops very close to the locality a shorter lead time of the occurrence of the winds will be specified in the warning bulletin.)
Impact of the Wind
  • Very light or no damage to low risk structures.
  • Light damage to medium to high risk structures.
  • Slight damage to some houses of very light materials or makeshift structures in exposed communities. Some banana plants are tilted, a few downed and leaves are generally damaged.
  • Twigs of small trees may be broken.
  • Rice crops, however, may suffer significant damage when it is in its flowering stage.
Precautionary Measures
  • When the tropical cyclone is strong or is intensifying and is moving closer, this signal may be upgraded to the next higher level.
  • The waves on coastal waters may gradually develop and become bigger and higher.
  • The people are advised to listen to the latest severe weather bulletin issued by PAGASA every six hours. In the meantime, business may be carried out as usual except when flood occur.
  • Disaster preparedness is activated to alert status.
What To Do
  • Inspect your house if necessary repair/fixing is needed.
  • Clean up drainage system.
  • Harvest crops tha can be yielded.
  • Monitor the latest Severe Weather Bulletin issued By PAGASA every six hours and hourly updates.

    Considering these developments, the public and disaster risk reduction and management offices concerned are advised to take all necessary measures to protect life and property. Persons living in areas identified to be highly or very highly susceptible to these hazards are advised to follow evacuation and other instructions from local officials. For heavy rainfall warnings, thunderstorm/rainfall advisories, and other severe weather information specific to your area, please monitor products issued by your local PAGASA Regional Services Division.