PTC 6 Designated in the Gulf of Mexico

September 8, 2024

The National Hurricane Center has started issuing advisories on PTC (potential tropical cyclone) 6 in the southwest Gulf of Mexico. The official forecast track is below and it is possible (with some uncertainty) that it could be a hurricane at landfall. I don't expect any crazy changes, but both the track and intensity forecast are a bit uncertain at this point. More details below if you're interested. 

It is important to note that this isn't a tropical cyclone yet, not even a tropical depression, as it still consists of an elongated north-south-ish trough of low pressure. The forecast track is based on a guess of where the center may consolidate but the NHC discussion notes that it could form anywhere along the trough axis (to the north or south of their guess). The general track forecast is well understood with an initial northwest motion followed by a turn to the north-northeast expected by midweek. But because of the uncertainty regarding the location and timing of the formation of a consolidated center it is of low confidence. The NHC also notes that some models have trended a bit to the east and that eastward shifts to the forecast may occur in the future. The current track could be right on, but I think an east-central Louisiana landfall is also a possibility, but I don't think we'll see it go farther to the east than that. It may take until late tomorrow or sometime Tuesday for the center to form and for confidence to improve.

The intensity ceiling is a bit higher than what I was thinking a few days ago. As shown, the official forecast calls for a hurricane at landfall but in their discussion they note that this level of intensification requires an interaction with another feature and is of low confidence at this point. Right now, a strong category 1 hurricane seems to be a reasonable ceiling. We've all seen how fast storms can intensify unexpectedly, so until we get a better picture of the forecast once the center forms, just know that a moderately stronger storm may be a possibility. We'll talk about potential impacts once we know more.

That's it for today. I'll send out another update if something changes or when the forecast confidence increases.

Chris