WxWatcher007

This is more long range speculation, but I do wonder if there’s a chance of remnants or something if the vorticity gets pushed back OTS after the original landfall. 00z euro and 12z gfs hint at it, but obviously that’s weenie range.

I was just going to post—no surprise being just over 100 hours out but the GEFS essentially follow the op but with more of a NC threat. Everything is still on the table but I’m not convinced this hooks well into SC. I think that’s an unusual track climatologically speaking.

Some of the second tier models still have a binary interaction that pulls future Imelda away, but with the Euro/GFS/AI models aligning at least right now that increases the risk to the coast substantially imo. Still, any one solution is far from guaranteed.

Yup building ridge to the north just traps it. Of course, that’s the furthest out and least confident part of the forecast.

There will be a window for significant intensification but idk how long it’ll be open for. You have near record warmth near the Bahamas and critically this should establish a nice outflow channel with a ULAC over the region and cutoff to the west. It’ll be in near ideal conditions. However, nearing the coast southerly shear could impart dry air and the immediate coastline has cooler SSTs. Folks should remember that major EC strikes are rare. Since 1990 it’s only been Andrew ‘92, Fran ‘96, and Jeanne ‘04.

Not surprising but quite a shift.

Reposting here.

I now believe that Invest 94L is a bona fide threat to the U.S. East Coast. Still, there is enormous uncertainty regarding the intensity and track of what is likely to become Imelda in the coming days. First, let's take a look at Humberto, which will play a critical role in the track of 94L. Although still sheared with the center likely west of the deeper convection, this tropical storm is on a clear organizing trend. The spacing between Humberto and 94L has been a point of discussion for days now. How close these two get will determine whether there will be a binary interaction. The GFS, which after sniffing out the potential for TC development in the SW Atlantic then kind of got lost in trying to consolidate the two waves, has clearly trended toward the Euro--to the extent you can with this much uncertainty in the setup. These are the last 5 GFS runs. Note how the trend has been two-fold. First, there is the obvious change that makes 94L stronger. That decreases the likelihood that it is absorbed by Humberto and given an escape route OTS. The second change is the spacing. It's subtle, but can be seen easily. A stronger and more organized 94L would likely have the outflow necessary to keep Humberto at bay. On the Euro, you see a similar trend with regard to spacing. Note how the escape routes of 1) Humberto and 2) NW flow in New England and SE Canada are blocked. These are the last 3 runs--not including this morning's 06z op run which continues the trend. The spacing difference is more than enough here to limit the impact of Humberto. Are we guaranteed a SE coast hit? Not at all. There are a lot of nuances remaining, including how quickly Humberto intensifies and its forward speed, the amplitude of the ridge and how it develops, and the amplitude of the cutoff over the CONUS. It is very clear, however, that 94L is poised to develop, and it poses a risk to at least the SE coast with regard to a direct hit, with possible impacts further north depending on track.

I wouldn't look at the verbatim output seriously yet. Look at the upper level pattern.

For New England, this one looks gone for now for a direct strike. The only "hope" would be what the 00z Euro showed and some sort of regeneration in the long range as the ridge rolls east. Or something like the EPS this hits the Carolina coast first but continues to be dragged northward with a more robust ECONUS cutoff. Even under that scenario, idk if we see a real EC runner and obviously the further inland the weaker it becomes. Though that would probably create a big rain setup. This is absolutely a legit threat for the southeast though. Fujiwhara is rare in the Atlantic for a reason, and even though Humberto is likely to become a major you look at 94L this morning and that's not a system that's just going to get absorbed. It may very well get going quickly once it can develop a LLC on the other side of Hispaniola.

No surprise but officially expected to become our next major now. Tropical Storm Humberto Discussion Number 2 NWS National Hurricane Center Miami FL AL082025 1100 PM AST Wed Sep 24 2025 The cloud pattern of Humberto has changed little in organization over the past several hours. Some rudimentary convective banding features are evident but the cold cloud tops are rather fragmented at this time. Upper-level outflow is being restricted over the western portion of the circulation, at least partially due to the outflow from disturbance 94L located near Puerto Rico. The current intensity estimate is set at 40 kt in agreement with a recently received scatterometer pass. The storm center is not yet very well-defined so the initial motion is a rather uncertain 300/10 kt. Over the next few days, Humberto should be steered generally west-northwestward to northwestward on the southwestern side of a subtropical mid-level high pressure area. The steering scenario for the tropical cyclone will likely become more complicated in 2-3 days due to the interaction with the developing system 94L to the west. The official forecast track is quite similar to the previous one, and roughly in the middle of the guidance. However, due to the likely complications in the evolution of the steering flow, there is lower than normal confidence in this track forecast. Global models suggest that there will be some relaxation in westerly vertical wind shear over Humberto in the coming days. This, along with very warm ocean waters and a moist mid-level air mass, should lead to strengthening. The system will probably become a hurricane in a couple of days, and then strengthen into a major hurricane. The official intensity forecast is in reasonable agreement with the simple and corrected model consensus, including the latest FSU Superensemble forecast. FORECAST POSITIONS AND MAX WINDS INIT 25/0300Z 20.7N 55.8W 40 KT 45 MPH 12H 25/1200Z 21.4N 56.7W 45 KT 50 MPH 24H 26/0000Z 21.9N 57.3W 50 KT 60 MPH 36H 26/1200Z 22.4N 57.9W 55 KT 65 MPH 48H 27/0000Z 22.9N 58.8W 60 KT 70 MPH 60H 27/1200Z 23.4N 60.1W 70 KT 80 MPH 72H 28/0000Z 24.0N 62.0W 85 KT 100 MPH 96H 29/0000Z 26.3N 66.0W 100 KT 115 MPH 120H 30/0000Z 30.1N 68.9W 100 KT 115 MPH $$ Forecaster Pasch/Blake

What was 12z and 18z?

More of the same in the 2020s? No thank you.

Still an OTS look verbatim.

Euro is showing a deep tropical feed through the region with the cutoff trough in the southeast and future Imelda moving north out of the Bahamas.

Not surprising that models are flip flopping all over the place. GFS after losing 94L for a while now develops it in the 18z run. Given how robust 94L has looked, I've always sold the idea that it wouldn't develop, but let's see how it handles interacting with the mountains of Hispaniola. Peak Season Forecast (Aug 20-Oct 20) Named Storms: 10 (3) Hurricanes: 6 (1) Major Hurricanes: 3 (1) Fernand, Gabrielle (MH), Humberto

Yeah there's one piece that seemingly wants to be in place, but unless the ridge is rolling over into SE Canada it's going to be hard to block an escape if this tries heading our way. We'll see how much, if any, things change as we get recon/balloon data and see how Humberto affects things. Part of me is wondering if Humberto takes off intensity wise and gets poleward faster for its escape if that closes the door for a future Imelda escape. I mean the 12z Euro (we sell for now) does what it does because that ridge builds over the top and into SE Canada before Imelda can escape. I still think if anything this is a Carolinas threat or OTS but we have a long way to go.

Close to MH status by day 5. Tropical Storm Humberto Discussion Number 1 NWS National Hurricane Center Miami FL AL082025 500 PM AST Wed Sep 24 2025 Satellite data indicates that Invest 93L over the central tropical Atlantic has now developed into Tropical Storm Humberto. Visible satellite imagery shows that throughout the day, the low-level center has become well-defined, with persistent and organized deep convection mainly located over the eastern side of the system. Subjective Dvorak intensity estimates from TAFB and SAB were both data-T/2.5 35 kt. DPRINT and DMINT Objective intensity estimates from UW-CIMSS range from 31 to 35 kt. Using these data, the initial intensity is set to 35 kt. The system is estimated to be moving west-northwestward at 300/13 kt, but this is of low confidence since the center has only recently formed. A west-northwestward to northwestward motion is anticipated through the next several days along the southwestern periphery of a mid-latitude ridge. Towards the end of the forecast period, an approaching trough moving offshore the east coast of the United States will erode the ridge and allow the system to turn more northward. However, there is quite a bit of uncertainty with the forward speed and cross-track spread of the system. This is increasingly apparent beyond day 3 as there are complex steering components with timing differences in the global models, including the approaching trough and potential binary interaction with Invest 94L. The NHC track forecast lies near the consensus aids given some of these uncertainties, and there is lower than normal confidence in the track forecast. The storm is within a favorable environment for strengthening with warm sea surface temperatures near 29C and moist mid-level RH values. The system will be dealing with some moderate westerly wind shear for the next day or so that will likely cause an asymmetric storm structure. EC and GFS SHIPS guidance depict the shear slightly weakening in the day 2 to 4 time frame, and with increasing divergence aloft, a slightly greater rate of strengthening is shown at that time. The latest NHC forecast follows these trends and lies near the consensus intensity aids. FORECAST POSITIONS AND MAX WINDS INIT 24/2100Z 20.1N 54.9W 35 KT 40 MPH 12H 25/0600Z 20.9N 56.0W 40 KT 45 MPH 24H 25/1800Z 21.6N 57.0W 45 KT 50 MPH 36H 26/0600Z 22.0N 57.5W 50 KT 60 MPH 48H 26/1800Z 22.5N 58.2W 55 KT 65 MPH 60H 27/0600Z 22.9N 59.0W 60 KT 70 MPH 72H 27/1800Z 23.6N 60.6W 70 KT 80 MPH 96H 28/1800Z 26.0N 64.3W 90 KT 105 MPH 120H 29/1800Z 29.1N 67.1W 95 KT 110 MPH $$ Forecaster Kelly

That’s happened to me several times already. They’ll have names soon enough. Imelda could’ve been retired the first time around. Second time’s the charm?

I may be wrong, but I don’t recall the NHC delivering key messages for an undesignated or non-PTC system.

Might be declared at 5pm with that LLC tucking under the convection on IR.

That may be the only thing that saves the east coast…

Disagree. 93L is far enough east it would’ve always been caught in that weakness and shipped out. 94L is exactly the kind of system that could threaten the EC this year—weak and buried in the Bahamas before finding itself potentially captured by a cutoff or blocked by an over the top ridge. We should all be selling the ops but the ensembles have been clear this is something to watch for the east coast if not a bona fide threat, which I’m not ready to call yet. NOAA is taking it seriously—we’re already getting key messages and recon out there. Edit: usual caveats for New England—meh, this no chance here, don’t waste your time.