2025 Global Model Runs Discussion (Out thru day 16)

[BobHarlem]

Stormcenter because it has no support from the eps/ GEPS ensembles and the op CMC and Euro runs dont have anything, the GFS has a very high false alarm rate of spinning up tropical systems in the SW caribbean, its actually a biacy the model has

A few members of EPS and GEFS both have the GFS System (more on the GEFS though), just a bit later in the range (June 12th+), however it's not a lot of support, but it's still a big difference from no support. Even those will probably bend more to the east pacific, but the idea of something happening in the general area isn't a bad take, just the mega hurricane impacts in any particular area.

[wxman57]

As is typical with the GFS and spurious storms, the date of landfall keeps shifting later. Last Wed/Thu, it was the 10th-11th along the Texas coast. It shifted landfall between south Texas and south Florida over the previous 16 runs, and now the landfall is back to Texas but on the 15th/16th. Don't believe it. I do think that a weak low may form offshore of the Carolinas this Thursday, as per the GFS, EC, and ICON. Could become a depression or weak TS during its very brief life.

[Stratton23]

Interesting to note their is a bit of a signal for potential mischief in the southern gulf/ bay of campache on the 12 EPS in the 10-12 day period

[revjohn]

I’ve been watching this setup evolve for about 3 weeks now — not just this week’s model runs. The progression of the MJO phase, the consistent warm SST anomalies, and the potential for a CAG-type genesis have all been lining up toward this early-June window. This isn’t something that suddenly appeared — it’s been developing in the background, and now we’re seeing the models start to reflect that timing.

I’m running an synthesis of the current model trends (raw GFS, GEFS, ECMWF EPS, SST anomaly fields, MJO phase, and steering pattern forecasts). Here’s where the data stack is pointing as of today’s 18z guidance:

Genesis potential remains high (~65%) in the western Caribbean → southern Gulf between June 7–9.
MJO phase is progressing on time, and SSTs are highly favorable across the region (+1.5 to +2.0 C anomalies).
Wind shear is dropping into a favorable range (<15 kt forecast in the western Gulf during the key window).

The deterministic GFS continues to run “hot” and unstable — swinging wildly between NE Gulf and W Gulf tracks — but this is not reflected in the ensemble means:

EPS and GEFS ensemble means still favor a WEST track — toward the NE Mexico / Deep South Texas corridor.
There is no consistent ensemble support for the recent “fantasy” major hurricane runs or sudden NE pulls.
Steering pattern (subtropical ridge) remains strong and west-centered in the critical window (~June 9–12), which supports a W/NW track into the western Gulf.
Upper trough depth does not appear sufficient to force a NE escape at this point.

Key risk to watch — if a system does track into the western Gulf under the current modeled ridge setup, dual ridge blocking/stalling becomes a legitimate concern → this is a far more meaningful risk to monitor than the precise landfall point being chased by deterministic runs.

Summary as of today’s data:

→ Development very plausible (~65% chance).
→ Track remains WEST-favored — NE Mexico / Deep S TX corridor still primary.
→ Deterministic GFS volatility is expected — ensemble guidance is stable — no eastward shift justified yet.
→ Stalling risk is real IF western Gulf landfall occurs.

I’ll be watching tonight’s EPS cycle closely → if that ridge structure holds, WEST remains the best-supported solution going into mid-June.

[Stratton23]

revjohn but it seems like the GFS is just on an island with this “ system” that it keeps putting up, maybe it is the CAG , but it could also be the GFS biacy with spinning up systems in that region of the caribbean

[revjohn]

Stratton23
Exactly — GFS deterministic is definitely acting on its usual early-season CAG bias here. That’s why I’m weighting EPS + GEFS ensemble trends higher right now — and so far they continue to show a stable west-favored signal. I still think genesis potential is solid (~65%), but the precise deterministic track/intensity swings are definitely model noise at this stage. The big story to me remains the ridge-driven steering and the potential for a stall if it does get into the western Gulf.

[Stratton23]

I guess time will tell, but the MJO going into phase 8 definitely argues that maybe the GFS isnt wrong in the idea of developing something, but yeah ive been watching the upper air steering pattern on the models / ensembles, definitely dont like seeing the weakness over texas but then steering collapses as we get a ridge out west and a ridge to the east, hopefully that doesnt verify

[revjohn]

Agreed — the MJO progression is definitely one of the reasons I’ve stayed in the camp that something developing is plausible here. I’m right with you on the steering concerns too — the idea of a collapsing flow between dual ridges is one of the more subtle but serious risks if we do end up with a western Gulf system. That’s why I’m watching the next couple EPS cycles so closely — if that ridge configuration holds, we could be looking at a much trickier situation than just track alone would suggest.

[Cpv17]

Interesting to note their is a bit of a signal for potential mischief in the southern gulf/ bay of campache on the 12 EPS in the 10-12 day period

I don’t see a strong enough signal yet on the EPS. For now I’m not concerned about it.

[revjohn]

Interesting to note their is a bit of a signal for potential mischief in the southern gulf/ bay of campache on the 12 EPS in the 10-12 day period

I don’t see a strong enough signal yet on the EPS. For now I’m not concerned about it.

That’s fair — the EPS isn’t showing a consolidated low yet at this range, but I’m still seeing a consistent signal in the mean for a lowering pressure field and clustering west of 90W in the 9–11 day window. Combined with the MJO phase progression, favorable SST anomalies, and the continuing ridge evolution, I think it’s still worth keeping this window on the radar. These CAG-evolved setups often don’t show a tight core this far out, but ensemble stability has actually been decent the last few cycles.

[Stratton23]

Cpv17 yes its small, but eventually i wouldnt be surprised to see it grow, MJO goes into phase 8 in the atlantic, that should help to get the ball rolling with the CAG becoming more active

[revjohn]

Latest 18z GFS continues to show the dual ridge pattern in place, which definitely keeps the stall/sluggish movement risk in play if we do get a western Gulf system. Still seeing the CAG remnant signature as well — with a broad low near Bay of Campeche and a consolidated surface low drifting NW. That said, the storm strength and exact position at hour 276 are very low confidence at this range, and ensemble guidance continues to point toward a west-favored track with more realistic timing (~June 8–9 genesis window). Pattern remains worth watching — especially if tonight’s EPS holds the current steering signals

[cycloneye]

Clearly a ghost is what 06z GFS has after the big delayed development timeframe that has pushed way back as in this run it starts at hour 270.

[BobHarlem]

Over/under on when GFS goes from a full blown hurricane to absolutely nothing.

I will say 6z on June 2 (before noon Monday).

Not quite, it was 0z June 3rd going to Mexico, and complelely gone by the 6z. Any energy it had is shifted into the east Pacific now. Although there's another new one to take its place way ahead on June 16th on the 6z , but it never makes it out of the Caribbean before the run ends (scratch that it does get into the gulf on the 19th as a 959mb storm -- a full week after what it was showing a few days ago). This may be a banner year for GFS phantom storms at this rate.

[cycloneye]

GFS trend last 5 runs is a very wild ride.

[tolakram]

I took the latest GFS run for the area off the east coast and went back 30 runs. No prediction in that area out past a few days, much less 250 hours plus. I don't care if the GFS has a signal, 99 times out of 100 it's complete nonsense.

[cycloneye]

The Euro ensembles are EPAC heavy and very limited to the AOI 10%, BOC and SW Caribbean.

[Stratton23]

Once the MJO moves into the basin, models are gonna light up like a christmas tree, ive seen this rodeo before, its quiet, but once you get that favorable mjo passage, its gonna switch

[revjohn]

Once the MJO moves into the basin, models are gonna light up like a christmas tree, ive seen this rodeo before, its quiet, but once you get that favorable mjo passage, its gonna switch

I’m still leaning toward development being plausible here — just likely a bit later than some of the earlier runs suggested. The CAG is real (as the EPAC side is now showing), and with the MJO progressing and favorable SSTs in place, I think we’re still in that “window setting up” phase. Agree with Stratton23 — once the MJO moves deeper into the basin and if the ridge pattern holds, I wouldn’t be surprised to see the ensembles start tightening up more. Still watching for the ~June 7–9 genesis window — no reason to call it a bust yet in my view.

[Ivanhater]

We have seen the GFS do this with a CAG, June system year after year. The first system moves to EPAC, but the gyre on the NE side is the one to watch after.