Lightnews — Scholar-powered news

sausiuswx.bsky.social @sausiuswx.bsky.social · 1d

To me at least it seems like Hispaniola (specifically DR) could be at greatest risk for catastrophic totals IF 98L stalls in the wrong place, aided by the local orography. At any rate totals capable of causing life-threatening flooding don't seem unreasonable at all, somewhere in the carribean (2/2)

sausiuswx.bsky.social @sausiuswx.bsky.social · 1d

My main concern are the widely expexted slow movement of 98L at some point. Tropical Cyclone flooding is way more dangerous then wind & someone seems likely gonna get rained on hard. But where? Hispaniola & to a lesser extend PR ? Jamaica ? Or Is there a way around it? (1/2)

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 1d

A reason why this may not matter much in the end is that in setups like this a narrow cresent of instability can develop along the cold front. If the cold front is defined enough and shear is high enough, a decent tornado threat could materialize, along with ofc severe wind (3/3)

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 1d

Tho at last in terms of the severe threat, it does tend to make the timing a bit worse and reduce the already limited overlap of decent CAPE with any high shear values. At present it still seems like some severe threat should be able to materialize (2/3)

1 1

sausiuswx.bsky.social @sausiuswx.bsky.social · 1d

SInce yesterday, we have seen a trend of the still strong mid to upper-level jet to the south. Not all models are as consistent with this trend but ECMWF and GFS are. Still could get a decent autumn storm for NW Europe and a HSLC severe setup out of this either way (1/3)

1 1 4

sausiuswx.bsky.social @sausiuswx.bsky.social · 2d

It appears to me that the 1st cluster of solutions for 98L (AOI #1) would be primarily a flooding threat for Hispaniola and/or Puerto Rico, while the 2nd cluster may have the potential for a bonified Major Hurricane to threaten areas like Cuba, Jamaica, Honduras and Nicaragua.

sausiuswx.bsky.social @sausiuswx.bsky.social · 2d

Since my last post, the uncertainty regarding 98L hasn't really reduced much. One interesting pattern that can be seen especially with the AI ensembles is that members that are stronger earlier turn north towards Hispaniola but those that don't appear to have higher potential intensities later on.

sausiuswx.bsky.social @sausiuswx.bsky.social · 2d

Since my last post, the uncertainty regarding 98L hasn't really reduced much. One interesting pattern that can be seen especially with the AI ensembles is that members that are stronger earlier turn north towards Hispaniola but those that don't appear to have higher potential intensities later on.

sausiuswx.bsky.social @sausiuswx.bsky.social · 2d

Still great uncertainty as to what Invest 98L will do. Formation is still (eventually) shown by most operational guides but timing varies widely. A look at attached. Ensembles also show great uncertainty as to the outcome. Interests in the central Carribean should monitor.

1 1

sausiuswx.bsky.social @sausiuswx.bsky.social · 2d

Tropical Storm Ramil did indeed strike the Phillipines on the earlier side of the guidance envelope earlier today and that obviously restricted its intensity. Heavy, potentially flooding rain still an issue tho. Thankfully Fengshen looks rather harmless in the South China Sea afterwards.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 4d

Regarding the intensity, current model guidance indicates that Ramil (96W) will most likely strike the Phillipines as a tropical storm, with a marginal typhoon likely being the ceiling. Landfall could occur as early as tmrw on more southern Solutions, otherwise likely Sunday.

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 4d

Regarding Invest 96W (RamilPH) it is noteworthy that both of the major AI ensembles (FNV3 and AIFS) are on the south side of the guidance envelope. FNV3 in particular even suggesting a landfall on Samar. Meanwhile GFS and its ensemble favoura a sharp re-curve towards N Luzon.

sausiuswx.bsky.social @sausiuswx.bsky.social · 7d

In the last roughly 24 hours we have actually seen a major correction to the north by the Google DeepMind ensembles. They now also have a spread of destinations for Invest 96W from northern Luzon to Taiwan. Operational guidance mainly still aimed at N Luzon. Next name: Fengshen.

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 8d

I missed the prime of Typhoon Nakri over the weekend. Now Nakri facing a triple punch of unfavourable shear, dropping SSTs and dry air swooping in during the next 24 hours. Nakri will increasingly interact with a frontal zone during the next 24 hours and start ETT tomorrow.

sausiuswx.bsky.social @sausiuswx.bsky.social · 8d

We now have tropical storm Lorenzo over the central Atlantic. It ain't pretty and it propably won't threaten land in a major way but it does exist. The track of this thing may end up being interesting tho, potentially looping around the Sutropical Ridge.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 8d

It is interesting that the Google DeepMind ensembles still aim 96W at the Philippines, while the biggest NWP ensembles (GEFS and ECENS) still generally aim the system further north, with some solutions like GFS operational threatening Taiwan.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 8d

Unfortuantely the potential for significant flooding from thunderstorms continues along parts of teh Balearic coast of Spain and the balearic islands today. This will likely also persist tomorrow, tho drifting east, as unseasonably moist air lingers. meteologix.com/uk/model-cha...

Model charts for Spain (Flash-Flood-Index, 6h maximum) | Central Europe Multi Model HD (3 days)

Central Europe Multi Model HD (3 days) - Current forecast valid for 10/13/2025, 09:00pm of parameter "Flash-Flood-Index, 6h maximum", model chart for map "Spain"

meteologix.com

4

sausiuswx.bsky.social @sausiuswx.bsky.social · 10d

Especially the G(E)FS, AIFS and the FNV3 ensemble seem to also fancy the formation of a tropical cyclone in the WPAC over the next 10 days. FNV3 has the signal more further south then GEFS. Conditions seem like they would allow for a Typhoon, too early for a concrete forecast tho

sausiuswx.bsky.social @sausiuswx.bsky.social · 10d

Karen is already dead. Moving over waters that are only 15-16°C (compared to 18-19°C at formation), while upper-level temperatures acc warmed slightly was always gonna be a death sentence. As a result, any remotely deep convection has quickly faded this afternoon/evening.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 10d

It is October 10th and I am watching the possibility of a tropical cyclone that may ultimately end up threatening land developing in the north (*checks notes again*) South(west) Indian ocean within the next 7-10days. Still early days but a very decent ensemble signal does exist.

sausiuswx.bsky.social @sausiuswx.bsky.social · 10d

Jerry is looking about as terrible as a tropical cyclone can look before it has to be un-designated. The LLC is sloppy, elongated and almost completely exposed. To describe the thunderstorm activity as 'organized' is even generous.

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 11d

Would you look at that, the folks at the NHC actually did it and named Subtropical Storm Karen northwest of the Azores. Karen won't be long for this world tho. She is already looking worse then at designation and things will only get worse as she moves over even colder waters.

1

sausiuswx.bsky.social @sausiuswx.bsky.social · 11d

Interesting little swirl (Invest 96L). I would have honestly called this a subtropical cyclone. Symmetrical windfield without major fronts, weak warm core etc. However NHC tends to be very strict with that. Now the system appears to be beyond its peak anyway.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 11d

Jerry really not looking healthy right now. What appears to be the vast majority of the LLC came literally shooting out from underneath the convection today and and is very sloppy too. ASCAT also showed a very elongated circulation earlier.

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 12d

Station data Hachijō-jima now proves that Halong brought Typhoon conditions (according to JMA scale) to the island. The measured 10 minute mean wind speed is now 118,4 km/h (74 mph). For now the estimated SLP bottomed out at 968.3 mbar (951.7 raw station (151 m ASL).

2

sausiuswx.bsky.social @sausiuswx.bsky.social · 12d

Synthetic aperture radar data from last evening (20:56:16 UTC ) indicated that Halong may have had 1 minute sustained wind speeds of 130 kts. That would have made it a Super Typhoon on JTWC scale. SAR can only provide estimates based off of ocean roughness. It isn't a direct measurement.

2