2025 Global Model Runs Discussion (Out thru day 16)

[TomballEd]

An active EPac rarely coexists with an active Atlantic.

[MetroMike]

An active Pacific means that the Atlantic basin will be more favorable into September once that area settles down.

[BobHarlem]

The 18z gfs is remarkably bare for the Atlantic for late August, that's for sure. Ensembles aren't showing all that much either.

[LAF92]

I’ve read where alot of experts are saying this could be a back loaded season. What is there thinking on that?

[cycloneye]

The big question is if September 10th (Peak Day) will be without a TC. Is not many times that the important date is without something out there. Let's see how things shape up for that date this year.

[WeatherBoy2000]

I’ve read where alot of experts are saying this could be a back loaded season. What is there thinking on that?

I believe it largely comes down to the now favorable sst configuration (warmth focused in the tropical/eastern Atlantic), the building -enso/la nina, a general trend towards back-loaded seasons in recent years, and the mjo becoming more favorable later in September.

[Steve]

I’ve read where alot of experts are saying this could be a back loaded season. What is there thinking on that?

It’s La Niña
https://www.ospo.noaa.gov/products/ocean/sst/anomaly/

and the MJO will have to rotate back to favorable phases.

[Steve]

I’ve read where alot of experts are saying this could be a back loaded season. What is there thinking on that?

It’s La Niña
https://www.ospo.noaa.gov/products/ocean/sst/anomaly/

and the MJO will have to rotate back to favorable phases.

Power is out here and both phones are almost toast, so it was a short reply. Just to expand a little La Niña years often feature later activity (mid September through at least some of October). MJO is going back into the circle for a bit. Once it’s back to 8/1/2 (assuming it will) there should be a flare up. Might be Mexican coast first then a propagation east particularly if we get any kelvin waves. Also the few minutes of Joe Bastardi I could stomach a couple weeks ago showed that the -VP height anomalies on the JMA would be negative up against the west coast of the continents (North America) and inside some of Mexico, Central America and western South America) which is in a slightly less favorable position than 2024 but conducive to rising air in the west Atlantic. That doesn’t mean we’ll get hit by anything on the Gulf or East Coasts, but there should be another several storms down the road.

[Stratton23]

Also another thing to watch over the coming weeks is models are showing several decent cold fronts sweeping down into the gulf over the next few weeks, always have to watch these fronts even in a period where the rest of the basin is quiet

[Steve]

Also another thing to watch over the coming weeks is models are showing several decent cold fronts sweeping down into the gulf over the next few weeks, always have to watch these fronts even in a period where the rest of the basin is quiet

Yeah there’s a couple of reasons. Sometimes they’ll leave back a piece of energy as we see from time to time or mesh with some energy and spin something up in the lower levels. Also cold fronts coming down usually correlate with the tropics coming up. Some people used to believe the old wives tale that fronts meant the season was over - and that was kind of conventional wisdom 30+ years ago. But we know better. Big cold (relatively) highs you always look underneath.

[Blown Away]

What is causing low after low to move off the mid Atlantic area? IMO, not much tropical action from the E or SE going to effect the CONUS with this pattern.

[Steve]

It’s the pattern. Hey LAF92, I went ahead and watched the first 12 minutes of Saturday summary (hurricane portion anyway), and it’s basically what I posted above. Probably worth your time to watch that portion which he’s got graphics.

[AnnularCane]

Also another thing to watch over the coming weeks is models are showing several decent cold fronts sweeping down into the gulf over the next few weeks, always have to watch these fronts even in a period where the rest of the basin is quiet

Yeah there’s a couple of reasons. Sometimes they’ll leave back a piece of energy as we see from time to time or mesh with some energy and spin something up in the lower levels. Also cold fronts coming down usually correlate with the tropics coming up. Some people used to believe the old wives tale that fronts meant the season was over - and that was kind of conventional wisdom 30+ years ago. But we know better. Big cold (relatively) highs you always look underneath.

Was that the case with Charley's front?

I believed that, although even then I knew the first front wasn't going to do it. The NOLA mets seemed to believe it. I don't know if they still do or not. But it's still a little hard to shake that notion.

[Hybridstorm_November2001]

An active EPac rarely coexists with an active Atlantic.

https://i.imgur.com/Dy6MFTC.png

I'm not going to lie, I'm surprised how overall inactive the Atlantic Basin has been thus far. Except for Erin, all the storms that formed have been short-lived, flare-up type systems. Hopefully, this trend will continue.

[Category5Kaiju]

An active EPac rarely coexists with an active Atlantic.

https://i.imgur.com/Dy6MFTC.png

I'm not going to lie, I'm surprised how overall inactive the Atlantic Basin has been thus far. Except for Erin, all the storms that formed have been short-lived, flare-up type systems. Hopefully, this trend will continue.

Really hope so too. But unfortunately, if recent years serve as any indication (major Gulf landfalls in the CONUS, backloaded seasons), I do think that we still have a lot of season to get through when September rolls around. Also, considering the talks of stability issues, sst anomaly issues, and that jazz earlier this summer and even this month, there's no doubt that Erin really put on a show and silenced the naysayers.

[Steve]

Also another thing to watch over the coming weeks is models are showing several decent cold fronts sweeping down into the gulf over the next few weeks, always have to watch these fronts even in a period where the rest of the basin is quiet

Yeah there’s a couple of reasons. Sometimes they’ll leave back a piece of energy as we see from time to time or mesh with some energy and spin something up in the lower levels. Also cold fronts coming down usually correlate with the tropics coming up. Some people used to believe the old wives tale that fronts meant the season was over - and that was kind of conventional wisdom 30+ years ago. But we know better. Big cold (relatively) highs you always look underneath.

Was that the case with Charley's front?

I believed that, although even then I knew the first front wasn't going to do it. The NOLA mets seemed to believe it. I don't know if they still do or not. But it's still a little hard to shake that notion.

I’m not a scientist so I can’t say with any credibility. My guess with Charley is that it was in an extreme weather pattern which was why it was part of it. So a correspondingly extreme example. I would have bet it was going toward Texas and posted that back in 2004 a couple days before it got pulled up. But that was a deep, sharp front coming down early that ended up being a harbinger of a dark season. Otherwise look south and sse of any cool high in the SEUS in September or October.

[BobHarlem]

336 Hour gfs ensembles, other than a short lived weak thing off a front along the Mid Atlantic, this looks more like June. Something at the tail end in the MDR, but not a strong signal (And not on operationals) One way I tell if we're active or not is if you can use the MLSP surface charts or percip models to find anything on the operational models, if you need to use the 850mb voracity to even find a hint, it's dead. Not even a hint of anything from 99L either.


Google Deep Mind Ensembles:



Could switch up by the second half of September, but for now it's still about as quiet as late August could be in the Atlantic. The one wave that does show up in the MDR in the ensembles leaves Africa on Labor Day, but it's not in any operationals.

[tropicwatch]

Time to watch the fronts. Forecast Models sometimes have a hard time sniffing out development from these features.

[StormWeather]

EURO hinting at a few circulations in the CPAC, and the 00Z run of Easterlywave had several members crossing the IDL and moving into the WPAC.

[cycloneye]

This is for September 10th (Peak day) and is not common to see it without TC's on that particular day. I guess there are not many years that are like this in the archives.