2025 WPAC Season

[cycloneye]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

[Hayabusa]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

https://i.imgur.com/BUvDp8p.jpeg

Interestingly Top 1 to 4 featured at least 1 super typhoon that reached 900 mb or below, these are from JTWC stats:
1983 - STY Forrest 876 mb
1984 - STY Vanessa 879 mb
1998 - STY Zeb 872 mb
2016 - STY Meranti 895 mb

[Kingarabian]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

https://i.imgur.com/BUvDp8p.jpeg

Interestingly Top 1 to 4 featured at least 1 super typhoon that reached 900 mb or below, these are from JTWC stats:
1983 - STY Forrest 876 mb
1984 - STY Vanessa 879 mb
1998 - STY Zeb 872 mb
2016 - STY Meranti 895 mb

Maybe the untapped WPAC warm waters plays a role.

[Ulf]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

The basin had a tropical depression in the South China Sea in February. So, the season technically already started.

[StormWeather]

I thought that 1998 was the latest start? It had 01W in July?

JtWC has 01W (Akang) on July 7th. There was a Unnumbered TD by JMA in May that the JTWC did not designate.

[cycloneye]

From Matthew Cuyugan at FB:

In an unusual scenario, no named tropical cyclone was recorded in the Northern Hemisphere (NHEM) as of May 25 for the first time since 1973!
Also, 2025 now moves to rank #7 in the latest-forming named storm in the Western Pacific (WPac) basin, surpassing the 2024 season.

[Ulf]

The last 5 WPAC seasons saw below average activity in either # of named storms or ACE for some reason. It seems that this year will continue this trend.

[al78]

Looks like the third latest start at least, another eight days with no storm will put it in the record books.

[Hayabusa]

Looks like the third latest start at least, another eight days with no storm will put it in the record books.

Euro and its AI show no named storm formation in the next 7 days, while uncle GFS is always drunk. It looks like 2025 would be beating 1984 but it's still fairly far from 1998 which is the record holder for the latest formation of the first named storm that formed on July 8.

[gib]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

https://i.imgur.com/BUvDp8p.jpeg

So is this year a new record? Or was 1998 really in July?

[StormWeather]

The 2025 season better start before June 8 or it may acend to #1 on late starts in history. Right now is #5.

https://i.imgur.com/BUvDp8p.jpeg

So is this year a new record? Or was 1998 really in July?

I think as of now the Western Pacific has reached the third latest start on record. It is now June 10th by UTC time so third place is a guarantee.

Invest 92W is slowly but surely getting better organized and it could become a TC within the next 24-48 hours.

[Hayabusa]

Some possible development with the low pressure area north of the Marianas, and in the later tau models develop another tropical system around the Marianas too.

[Hayabusa]

Some possible development with the low pressure area north of the Marianas, and in the later tau models develop another tropical system around the Marianas too.

EC-AIFS's track on the possible next TC is more west than Euro and GFS, showing entering the Philippine area of responsibility and becoming a strong typhoon.

[cycloneye]

Should be 96W soon.

[cycloneye]

Look at 12z GFS how it bombs future 96W. Lowest pressure is 918 mbs and makes landfall in central Japan.

[Hayabusa]

The convection just west of Luzon may need watching for development too

[cycloneye]

Euro ensembles are very bullish with the next one.

[cycloneye]

Guam and other Mariana Islandsare with heavy rains caused by the disturbance that will develop later this week.

Hydrologic Outlook
National Weather Service Tiyan GU
Issued by National Weather Service Honolulu HI
1202 AM ChST Wed Jun 25 2025

...HEAVY RAINFALL REMAINS POSSIBLE LATE WEEK AND THROUGH THE
WEEKEND...

This Hydrologic Outlook is for Guam, Rota, Tinian and Saipan.

A tropical disturbance anticipated to develop later this week is
still expected to bring widespread showers from as early as Thursday
evening through Sunday, some of which could be heavy. A surface
trough approaching from Chuuk State is expected to link with the
monsoon trough over the Philippine Sea in the coming days. A
circulation is expected to develop Thursday or Friday and help focus
heavier showers over the Marianas. Though there is still significant
uncertainty on the location and timing of the disturbance, the
common theme is the increasing likelihood for heavier showers that
could result in flash flooding.

Through Sunday night, Guam and the CNMI could see rainfall amounts
of 5 to 10 inches. This type of rainfall would be supportive of minor
flooding across the islands, but the concern is for the threat of
heavier showers resulting in flash flooding.

Residents in the Marianas should continued closely monitoring this
developing situation as flood watches, advisories and warnings could
be issued later.

[Hayabusa]

12z, models except GFS are in a general WNW track

[cycloneye]