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Japan Meteorological Agency, 369Toranomon, Minato (2026)

26/05/2026

TROPICAL DEPRESSION FORECAST
Issued: May 26, 2026 — 1:05 PM JST(Based on JMA analysis at May 26, 2026 — 12:00 PM JST / 03:00 UTC May 26)

At 12:00 PM JST, the center of Tropical Depression a was estimated based on all available data near 8.4°N, 140.4°E, about 280 km east-southeast of Colonia, Yap. The system is moving west-northwest slowly.
▪️ Central pressure: 1004 hPa
▪️ Maximum sustained winds near center: 55 kph
▪️ Maximum gusts: 85 kph

24-Hour Forecast (Valid May 27, 2026 — 12:00 PM JST)Forecast center: 9.5°N, 137.3°E — about 90 km west of Colonia, Yap.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1002 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 95 kph
▪️ Radius of probability circle: 130 km
▪️ Grade: Tropical Storm

45-Hour Forecast (Valid May 28, 2026 — 9:00 AM JST)
Forecast center: 12.3°N, 136.0°E — about 386 km northwest of Colonia, Yap.
▪️ Movement: north-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 85 kph
▪️ Maximum gusts: 120 kph
▪️ Radius of probability circle: 200 km
▪️ Grade: Tropical Storm

69-Hour Forecast (Valid May 29, 2026 — 9:00 AM JST)
Forecast center: 15.2°N, 134.4°E — about 1017 km east-northeast of San Policarpo, Eastern Samar.
▪️ Movement: north-northwest at 15 kph
▪️ Central pressure: 990 hPa
▪️ Maximum sustained winds: 100 kph
▪️ Maximum gusts: 150 kph
▪️ Radius of probability circle: 260 km
▪️ Grade: Severe Tropical Storm

93-Hour Forecast (Valid May 30, 2026 — 9:00 AM JST)Forecast center: 17.8°N, 132.3°E — about 960 km northeast of San Policarpo, Eastern Samar.
▪️ Movement: northwest at 15 kph
▪️ Central pressure: 985 hPa
▪️ Maximum sustained winds: 100 kph
▪️ Maximum gusts: 150 kph
▪️ Radius of probability circle: 330 km
▪️ Grade: Severe Tropical Storm

117-Hour Forecast (Valid May 31, 2026 — 9:00 AM JST)Forecast center: 20.3°N, 130.6°E — about 900 km east of Basco, Batanes.
▪️ Movement: north-northwest at 15 kph
▪️ Central pressure: 980 hPa
▪️ Maximum sustained winds: 110 kph
▪️ Maximum gusts: 155 kph
▪️ Radius of probability circle: 440 km
▪️ Grade: Severe Tropical StormForecast

Outlook
Tropical Depression a is currently moving slowly west-northwestward over the western Pacific Ocean. The system is forecast to steadily intensify over the next 24 hours, upgrading to a Tropical Storm as it passes just west of Yap. By Thursday, the system will turn more north-northwestward across the Philippine Sea while continuously gathering strength. It is expected to upgrade into a Severe Tropical Storm by Friday, maintaining this high intensity over the weekend as it moves northwestward. While the storm is projected to remain well east of the Philippine landmass, its outer circulation will track along the eastern margins of the Philippine Area of Responsibility through Sunday.

Potential Impacts
▪️ Marine Hazards: Very rough to high seas are expected to develop around Yap State tonight through Wednesday as the storm intensifies and passes nearby. Swells generated by this system are forecast to propagate westward, reaching the eastern seaboard of Northern Luzon and the Batanes sector by Sunday, creating hazardous conditions for small watercraft.
▪️ Rainfall: Moderate to heavy rain is anticipated over Colonia and surrounding outer islands from Tuesday night into Wednesday, bringing a risk of localized flooding. No direct rainband impacts are expected for mainland sections of the Philippines, though peripheral cloudiness could affect extreme Northern Luzon by late Sunday.
▪️ Wind: Gusty conditions will affect Yap State starting tonight, with gale-force winds expanding up to 95 kph near the center by Wednesday afternoon. Wind impacts for the Philippine landmass are currently projected to be negligible, though open waters over the northern Philippine Sea will experience storm-force gusts up to 155 kph over the weekend.

26/05/2026

As of 12:00 PM today (Japan Standard Time), the Low Pressure Area (LPA) being monitored in the Pacific Ocean has developed into a tropical depression.

It is expected to rapidly intensify in the coming hours.

25/05/2026

The Low Pressure Area (LPA) being monitored in the Pacific Ocean could develop into a tropical depression at any moment, and it has the potential to rapidly intensify into a tropical storm.

21/05/2026

An LPA (Low Pressure Area) has formed over the Pacific Ocean, located 757 km East of Mati City, Davao Oriental. It is moving slowly to the west.

Meanwhile, the Southwest Monsoon (Habagat) continues to bring rain to Southeast Asia, including Myanmar, Laos, Vietnam, Thailand, Cambodia, Bangladesh, and Malaysia. Please watch out for floods and landslides.

🌬 High Winds & Developing StormsOur primary concern is a developing low-pressure system (1002 hPa) currently positioned over the Sea of Japan at 37N 133E.

Movement: Tracking east-northeast at 15 knots.

Impact: Expect a rapid increase in winds over the next 6 hours. Gale-force winds between 30 to 35 knots are anticipated within 800 miles in the low's western semicircle, and up to 400 miles in all other directions.

Just to the east, a second 1004 hPa low at 36N 143E is moving steadily eastward at 15 knots, further complicating conditions along the major shipping routes.

🌫️ Severe Dense Fog Warnings
Visibility is a major hazard tonight. We have issued two urgent warnings for dense, localized fog:

Regional Seas: Heavy fog is impacting the Sea of Okhotsk, Sea of Japan, Yellow Sea, and the East China Sea.

Open Pacific: A massive blanket of dense fog is stretching across the Northwest Pacific. This hazardous zone is bounded roughly from the coast of Japan (near 36N 141E), extending northeast past the Kuril Islands up toward the Bering Sea (60N 172E), and looping south into the Philippine Sea (24N 128E). Mariners in these coordinates should prepare for near-zero visibility.

🗺️ Fronts and Surrounding Systems
A complex network of weather fronts is draped across the region:

Active Fronts: A 1004 hPa low at 42N 157E is anchoring a warm front stretching southeast toward 39N 163E, and a cold front trailing southwest toward 38N 149E.

Stationary Front: A massive, stalled front stretches all the way from Southern China (23N 110E), cutting across the East China Sea, riding right along the southern coast of Japan, and extending out into the Pacific past 147E. Expect prolonged overcast skies and unsettled weather along this line.

Other Lows: We are monitoring a weak 1004 hPa low drifting slowly east-southeast near the Korean Peninsula (36N 126E), and a tropical 1008 hPa low-pressure area drifting slowly west in the Philippine Sea near 06N 133E.

High Pressure: Fairer weather dominates further east, anchored by a strong 1022 hPa high racing east at 30 knots near 39N 175E, and two weaker 1018 hPa highs shifting over the Sea of Okhotsk and the central Pacific.

19/05/2026

"THE BEGINNING OF THE SOUTHWEST MONSOON"

The Southwest Monsoon winds are starting to be felt in SOUTHEAST ASIA, including MYANMAR, THAILAND, CAMBODIA, AND VIETNAM. Expect frequent rainfall in the aforementioned areas. Meanwhile, the breeze of the southwest monsoon is expected to be felt in the PHILIPPINES by the end of MAY.

On the other hand, it is currently very hot and there are many cloud clusters over the Pacific Ocean. Because of this, a tropical cyclone is expected to form by the end of MAY or the first week of JUNE this year.

14/05/2026

3-Day Weather Surface Analysis Explanation (JMA Charts)

Current Surface Analysis
(Valid 1400 UTC May 7, 2026)

Strong Low Pressure East of Japan
•A well-developed low pressure system is located east of Japan.
•The tightly packed isobars (lines of equal pressure) indicate strong winds and rough seas around the system.
•Cold fronts extend southward from the low.

High Pressure over Japan
•A high pressure area near Japan brings relatively stable weather to parts of the country.
•However, nearby fog areas suggest moist air and reduced visibility in some regions.

Several Weak Low Pressure Systems over China and Russia
•Multiple low pressure systems are scattered over mainland Asia.
•These systems may bring unsettled weather, rain showers, and cloudy conditions

Tropical Depression South of Japan and East of the Philippines
•A tropical depression with pressure around 1006 hPa is seen south of Japan.
•At this stage it is weak, but it could enhance rain and thunderstorms over nearby waters.

Expected Weather
•Japan: Windy and cloudy in eastern parts due to the nearby low pressure system.
•Philippines: Mostly warm and humid with isolated thunderstorms from the tropical disturbance.
•East China/Korea: Variable weather with occasional rain from weak low pressure systems.

24-Hour Forecast
(Forecast for 1400 UTC May 8, 2026)

Deepening Low Pressure East of Japan
•The low pressure system intensifies further to around 980 hPa.
•Stronger pressure gradients mean stronger winds and rougher seas.

Cold Front Moves Eastward
•The cold front stretches farther south and east over the Pacific Ocean.
•Cooler and drier air follows behind the front.

High Pressure Expands over Japan
•The high pressure system strengthens to around 1020 hPa.
•This improves weather conditions in central and western Japan.

Fog Continues
•Fog remains around coastal regions and nearby seas due to moist air interacting with cooler temperatures.

Expected Weather
•Northern Japan: Windy with possible rain and high waves.
•Central/Southern Japan: Gradual improvement with sunnier skies.
•Western Pacific: Rough marine conditions due to the deep low pressure.
•Philippines: Tropical depression remains weak but may continue producing scattered rain showers.

48-Hour Forecast
(Forecast for 1400 UTC May 9, 2026)

Low Pressure System Moves Farther Northeast
•The powerful low shifts away from Japan toward the North Pacific.
•Although still intense, its direct effects on Japan begin to weaken.

High Pressure Dominates Japan
•Stronger high pressure (around 1026 hPa) spreads across Japan.
•This generally brings fair and more stable weather.

Cold Front Moves Away
•The front continues moving eastward into the Pacific Ocean.
•Weather behind the front becomes cooler and calmer.

Tropical Depression Remains Weak
•The tropical depression south of Japan still exists but shows no rapid intensification in this forecast.

Expected Weather
•Japan: Improved weather conditions with clearer skies and calmer winds.
•North Pacific: Stormy marine conditions remain around the deep low pressure area.
•Philippines and nearby seas: Continued chance of thunderstorms and localized rain showers.

3-Day Weather Trend
Japan
•Starts with unsettled and windy weather due to a strong low pressure system.
•Conditions gradually improve as high pressure builds in.

Western Pacific
•A strong ocean storm intensifies and moves northeastward.
•Rough seas and strong winds are likely for ships and coastal waters.
Philippines
•No major typhoon development shown during this period.
•A weak tropical depression may still bring occasional rain and thunderstorms.
Important Marine Impacts
•Strong winds and high waves near the deep low pressure system.
•Fog may reduce visibility for ships and aircraft.
•Safer marine conditions gradually return near Japan by Day 3.

07/05/2026

Tropical Storm "Hagupit" FYI.. 🌀🌀🌀

"Hagupit" is a Filipino word that means "to lash," "to flog," or "to strike with strong force". Contributed by the Philippines to the western North Pacific tropical cyclone naming list, it signifies a powerful or destructive impact.

07/05/2026

TROPICAL STORM FORECAST
Issued: May 7, 2026 — 12:45 PM JST
(Based on JMA analysis at May 7, 2026 — 12:00 PM JST / 03:00 UTC May 7)

At 12:00 PM JST, the center of Tropical Storm Hagupit (T2605) was estimated based on all available data near 7.4°N, 143.1°E, about 598 km east-southeast of Colonia, Yap. The system is moving west at 15 kph.
▪️ Central pressure: 1002 hPa
▪️ Maximum sustained winds near center: 65 kph
▪️ Maximum gusts: 90 kph

12-Hour Forecast (Valid May 8, 2026 — 12:00 AM JST)
Forecast center: 8.1°N, 142.1°E — about 479 km east-southeast of Colonia, Yap.
▪️ Movement: northwest at 10 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 75 km
▪️ Grade: Tropical Storm

24-Hour Forecast (Valid May 8, 2026 — 12:00 PM JST)
Forecast center: 8.8°N, 140.2°E — about 271 km southeast of Colonia, Yap.
▪️ Movement: west-northwest at 20 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 105 km
▪️ Grade: Tropical Storm

45-Hour Forecast (Valid May 9, 2026 — 9:00 AM JST)
Forecast center: 9.8°N, 137.1°E — about 116 km west-southwest of Colonia, Yap.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 185 km
▪️ Grade: Tropical Storm

69-Hour Forecast (Valid May 10, 2026 — 9:00 AM JST)
Forecast center: 11.1°N, 134.5°E — about 961 km east of Guiuan, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 260 km
▪️ Grade: Tropical Storm

93-Hour Forecast (Valid May 11, 2026 — 9:00 AM JST)
Forecast center: 12.4°N, 131.3°E — about 632 km east-northeast of San Policarpo, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1004 hPa
▪️ Radius of probability circle: 320 km
▪️ Grade: Tropical Depression

Forecast Outlook
Tropical Storm Hagupit (T2605) has slowed its westward movement slightly but remains on a track toward the Yap State region. The system is forecast to gradually intensify over the next 24 hours, likely reaching its peak strength tomorrow as it passes to the south of Yap. On Saturday, the storm will track across the Philippine Sea, maintaining tropical storm strength before encountering more hostile atmospheric conditions by Monday. A steady weakening trend is expected as it approaches the Philippine Area of Responsibility, likely degrading into a Tropical Depression before reaching the coast of Eastern Samar.

Potential Impacts
▪️ Marine Hazards: Expect very rough sea conditions to develop around Yap and the surrounding outer islands tonight through Friday. Wave heights near the center may exceed 4.0 meters. Swells from this system are expected to reach the eastern seaboards of the Philippines by Sunday afternoon, potentially creating hazardous conditions for small seacraft.
▪️ Rainfall: Heavy rain is anticipated for Colonia and surrounding atolls starting Friday morning, with the risk of localized flooding. In the Philippines, rainbands from the weakening system may bring scattered showers to Guiuan and San Policarpo by Monday evening.
▪️ Wind: Strong winds and gale-force gusts up to 110 kph are likely in Yap State by Friday afternoon as the storm center makes its closest approach. Wind impacts for the Philippines are currently expected to be minimal, though gusty conditions may occur along the Samar coastline early next week.

07/05/2026

TROPICAL STORM FORECAST
Issued: May 7, 2026 — 9:45 AM JST
(Based on JMA analysis at May 7, 2026 — 9:00 AM JST / 00:00 UTC May 7)

At 9:00 AM JST, the center of Tropical Storm Hagupit (T2605) was estimated based on all available data near 7.8°N, 143.7°E, about 648 km east-southeast of Colonia, Yap. The system is moving west-northwest at 20 kph.
▪️ Central pressure: 1002 hPa
▪️ Maximum sustained winds near center: 65 kph
▪️ Maximum gusts: 90 kph

12-Hour Forecast (Valid May 7, 2026 — 9:00 PM JST)
Forecast center: 8.0°N, 142.5°E — about 518 km east-southeast of Colonia, Yap.
▪️ Movement: west at 10 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 75 km
▪️ Grade: Tropical Storm

24-Hour Forecast (Valid May 8, 2026 — 9:00 AM JST)
Forecast center: 8.8°N, 140.8°E — about 335 km southeast of Colonia, Yap.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 105 km
▪️ Grade: Tropical Storm

48-Hour Forecast (Valid May 9, 2026 — 9:00 AM JST)
Forecast center: 9.8°N, 137.1°E — about 116 km west-southwest of Colonia, Yap.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 185 km
▪️ Grade: Tropical Storm

72-Hour Forecast (Valid May 10, 2026 — 9:00 AM JST)
Forecast center: 11.1°N, 134.5°E — about 961 km east of Guiuan, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 260 km
▪️ Grade: Tropical Storm

96-Hour Forecast (Valid May 11, 2026 — 9:00 AM JST)
Forecast center: 12.4°N, 131.3°E — about 632 km east-northeast of San Policarpo, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1004 hPa
▪️ Radius of probability circle: 320 km
▪️ Grade: Tropical Depression

Forecast Outlook
Tropical Storm Hagupit (T2605) continues its track across the Western Pacific, currently moving west-northwest toward the Yap State region. The system is expected to maintain its intensity as a Tropical Storm over the next 48 hours, reaching its peak strength between Friday morning and Saturday morning. On its current trajectory, Hagupit will pass south of Colonia, Yap on Saturday morning before continuing toward the Philippine Sea. Environmental conditions are expected to become less favorable by Monday, leading to a steady weakening of the system into a Tropical Depression as it approaches the eastern seaboard of Samar.

Potential Impacts
▪️ Marine Hazards: Rough to very rough seas will persist across the waters of Micronesia, particularly near Yap and surrounding atolls. Mariners in the eastern seaboards of the Philippines should anticipate increasing swells and deteriorating sea conditions by late Sunday or early Monday.
▪️ Rainfall: Moderate to heavy rainfall is expected in Colonia, Yap, and nearby islands beginning Friday as the system makes its closest approach. Localized flooding and minor landslides are possible in high-risk areas. For the Philippines, light to moderate rains associated with the system's outer circulation may reach Eastern Samar by Monday morning.
▪️ Wind: Tropical storm-force winds with gusts reaching 110 kph are likely for Yap State between Friday night and Saturday morning. In the Philippines, the risk of significant wind impact remains low, though breezy conditions may develop along the coastal areas of San Policarpo and Guiuan as the system nears the region as a weakening depression.

06/05/2026

TROPICAL STORM FORECAST
Issued: May 6, 2026 — 9:45 PM JST
(Based on JMA analysis at May 6, 2026 — 9:00 PM JST / 12:00 UTC May 6)

At 9:00 PM JST, the center of Tropical Storm Hagupit (T2605) was located near 7.5°N, 145.8°E, about 876 km east-southeast of Colonia, Yap. The system is moving west-southwest at 15 kph.
▪️ Central pressure: 1002 hPa
▪️ Maximum sustained winds near center: 65 kph
▪️ Maximum gusts: 90 kph

12-Hour Forecast (Valid May 7, 2026 — 9:00 AM JST)
Forecast center: 7.8°N, 143.5°E — about 624 km east-southeast of Colonia, Yap.
▪️ Movement: west at 20 kph
▪️ Central pressure: 1002 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 55 km
▪️ Grade: Tropical Storm

24-Hour Forecast (Valid May 7, 2026 — 9:00 PM JST)
Forecast center: 8.2°N, 141.8°E — about 433 km southeast of Colonia, Yap.
▪️ Movement: west at 15 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 80 km
▪️ Grade: Tropical Storm

48-Hour Forecast (Valid May 8, 2026 — 9:00 PM JST)
Forecast center: 9.4°N, 138.3°E — about 23 km south-southwest of Colonia, Yap.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 155 km
▪️ Grade: Tropical Storm

72-Hour Forecast (Valid May 9, 2026 — 9:00 PM JST)
Forecast center: 10.4°N, 135.3°E — about 1,048 km east of Guiuan, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 998 hPa
▪️ Maximum sustained winds: 70 kph
▪️ Maximum gusts: 110 kph
▪️ Radius of probability circle: 220 km
▪️ Grade: Tropical Storm

96-Hour Forecast (Valid May 10, 2026 — 9:00 PM JST)
Forecast center: 11.6°N, 132.6°E — about 753 km east of Guiuan, Eastern Samar.
▪️ Movement: west-northwest at 15 kph
▪️ Central pressure: 1000 hPa
▪️ Maximum sustained winds: 65 kph
▪️ Maximum gusts: 90 kph
▪️ Radius of probability circle: 280 km
▪️ Grade: Tropical Storm

120-Hour Forecast (Valid May 11, 2026 — 9:00 PM JST)
Forecast center: 12.8°N, 130.4°E — about 536 km east-northeast of San Policarpo, Eastern Samar.
▪️ Movement: west-northwest at 10 kph
▪️ Central pressure: 1004 hPa
▪️ Radius of probability circle: 330 km
▪️ Grade: Tropical Depression

Forecast Outlook
Tropical Storm Hagupit (T2605) continues to move through the Micronesian region and is currently projected to pass extremely close to Colonia, Yap within the next 48 hours. The system will likely reach its peak intensity during this passage, bringing tropical storm-force winds and high gusts to the area. After moving past Yap, Hagupit will continue its west-northwest track across the Philippine Sea toward the Eastern Visayas. By Monday evening, May 11, the system is expected to encounter less favorable conditions and weaken into a Tropical Depression as it approaches the vicinity of San Policarpo.

Potential Impacts
▪️ Marine Hazards: Very rough seas are expected around Yap State starting tonight. Wave heights near the storm's center may reach 4.5 meters. Small seacraft in the eastern seaboards of Samar should begin monitoring sea conditions, as swells from the system will likely reach the Philippine coast by Sunday.
▪️ Rainfall: Heavy rainfall is imminent for Colonia, Yap, and surrounding atolls through Friday, which may lead to localized flooding. For the Philippines, outer rainbands may begin to affect the coastal towns of Guiuan and San Policarpo by Monday afternoon as the system nears the boundary.
▪️ Wind: Strong gale-force gusts up to 110 kph are expected in Colonia, Yap by Friday night as the storm center passes just to its south-southwest. In the Philippines, wind impacts remain low for the next 4 days, though occasional gusty conditions may develop along the eastern shores of Samar by early next week.

Japan Meteorological Agency

26/05/2026

26/05/2026

25/05/2026

21/05/2026

19/05/2026

14/05/2026

07/05/2026

07/05/2026

07/05/2026

06/05/2026

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