MANUAL WEATHER TRACKER _

[OCT 23 02:00 UTC TIME] CURRENT SITUATION OVERVIEW

NATL

• Melissa Melissa is currently a tropical storm located in the Carribean sea. As multiple agencies (such as JTWC) has mentioned, it is expected to undergo rapid intensification over the next few days in this region. Due to its slow movement, during its impact to Jamaica and Cuba, it may last for longer than a day (24h). There is essentially zero vertical wind shear in this patch of the ocean, alongside high ocean heat content (OHC), this *will* become a very significant storm.

[OCT 9 11:00 UTC TIME] CURRENT SITUATION OVERVIEW

WPAC

• NakriFormerly 95W, Nakri has intensified into a tropical storm. The system remains disorganised and very assymetrical. Current atmospheric conditions seem unfavourable for significant intensification due to shear in the upper atmosphere. However, that does not dismiss the dangers that any tropical system may bring. The storm should be monitored closely in the upcoming days in case of a close approach south of mainland Japan by this weekend.
SYSTEM STATUS (Nakri): CAUTION


• HalongMeanwhile, Halong (centred around 33º 42'N, 144º 52'E), has weakened back to category 2 after yesterday's peak as a cat 4 storm. Official ECMWF estimates the storm to have wind speeds of 175km/h (10min sustained), while JTWC suggests 1min sustained of 215km/h. The storm seem to have completed an eye replacement cycle (ERC) yesterday night. Extratropical transition is currently ongoing, which Halong will remain as a strong extratropical cyclone for tomorrow. Due to the combined effect of ERC and ET, it may explain the significant weakening of the storm. Otherwise, perhaps an unsuccessful ERC has occured, as the system does seem to be more assymetrical currently. As Halong tracks further away from shore, potential dangers to coastal communities should decrease. Despite that, marine conditions in the storm's coverage may remain violent.
SYSTEM STATUS (Halong): DANGEROUS SYSTEM

EPAC

• Priscilla Priscilla has weakened to a category 1 system and continues to dissipate. Low altitude and warm cloud tops suggest further (significant) weakening of the storm in process. However, rain associated with the storm may pose dangers of flash flooding, if Priscilla were to make landfall. With that said, I do not expect Priscilla to be dangerous in terms of wind, but more so due to its associated precipitation.

[OCT 8 06:00 UTC TIME] CURRENT SITUATION OVERVIEW

WPAC

• 95WAccording to ECMWF, 95W has intensified into a tropical depression. However, the system is very assymetrical and disorganised. Weather models seem to be in agreement that 95W will take a NW track in the upcoming days until a sharp turn to northeast this weekend. There is still significant high level shear north of the system, which will hinder its ability to intensify.
SYSTEM STATUS (95W): WATCH CLOSELY


• HalongHalong has intensified into a dense category 4 system over last night. However, due to the system's small size and distance from the east coast of Japan, it should not cause significant impact. That said, its cloud coverage and outer rainbands may affect the general areas around Chiba later tonight (Japan time) according to forecasts, so it should be advised to be cautious of flooding or landslides in areas such as lowlying areas or with poor drainage. It should be advised that the general public should avoid activities in the water for today and tomorrow. Additionally, the system's interaction with shear to its west will cause the system to weaken gradually over the next few days.
SYSTEM STATUS (Halong): VERY DANGEROUS SYSTEM

EPAC

• Priscilla Priscilla is currently a category 2 system roughly 313km (169nm / 194.5mi) southwest of Cabo San Lucas. The storm's rain is affecting the area, so it should be advised to be cautious of flooding or landslides in areas such as lowlying areas or with poor drainage. The system's cloud tops to its right half seems abnormally warm and low in altitude, despite the lack of significant wind shear. A patch of abnormally cool water in its right-back quadrant may be to blame, but since I'm no meteorologist, let the experts figure it out. Nonetheless, the dangers that a tropical cyclone poses are still relevant and should not be dismissed, despite its distance from shore.

[OCT 7 17:00 UTC TIME] CURRENT SITUATION OVERVIEW

On Invest 95W: My "forecast" without any solid data proving it

The Western Pacific basin has been very active, and has produced some impressive storms lately (namely, Ragasa and Neoguri) and this trend seem to be continuing. Currently, Severe Typhoon Halong is a major system located ~550km (~297nm) south/southeast to the shores of Kushimoto. Around ~1450km (~783nm) south/southeast to Halong is invest 95W. This distance is exactly at the ceiling for the Fujiwhara effect to take place, if 95W were to intensify into a tropical depression in the coming day. With Invest 95W taking a northwestern track over the past day, we may be able to witness the effect at play after what Hurricane Humberto and Imelda demonstrated earlier last week. That said, even with sufficient OHC (current ocean temperatures seem to be around 30ºC), an easternly upper-atmosphere jetstream at 200hPa may hinder the system's development and movement speed. Additionally, with Halong expected to turn northeastward hastly, the probability of the effect happening is extremely low. That said, with the combined effect of Halong and two high pressure systems to its northeast and mainland China, the system may take a more northwesternly path for the upcoming days before trending northeast due to the effect of Halong.

What the models are currently saying (based on Windy's colour-coded lines):

• ECMWF ECMWF seem to agree with my above analysis and expect a close approach to the southeast of Kyushu island by October 13. Based on my intensity calculator, the storm may approach as a weak Category 1 system.
• GFS GFS seem to doubt the system's ability to intensify and breaking apart by Oct 10, even though the system will attempt to reorganise as extratropical transition begins.