Firsthand Weather is keeping a close eye on the Gulf of Mexico this week as the remnants of Tropical Storm Harvey move into the southwestern Gulf. Impacts to the United States are looking more likely–especially for Texas then there’s the potential the remnants may impact additional Gulf States (Louisiana, southern Arkansas, Mississippi, Alabama, and Tennessee), so I wanted to provide a brief post on the latest spaghetti plot with you all.
The National Hurricane Center (NHC) is monitoring the remnants of Harvey (currently crossing the Yucatan Peninsula), and is giving the low a 70% of tropical cyclone development over the next 48 hours and an 90% chance of tropical cyclone development over the next five days. The current analyses show decent spherical vorticity, light environmental shear ahead of the system in the Bay of Campeche, and above average sea-surface temperatures. This should allow the remnants to develop into a tropical cyclone by Wednesday afternoon. It is possible the NHC may label this as a Potential Tropical Cyclone by the afternoon hours today, which would allow local National Weather Service offices to begin issuing weather products (watches) on this system.
Numerical guidance has begun trending further northward over the past few runs. This has shifted the potential track from northern Mexico, more towards the Texas coast. This means the entire Texas coast needs to keep a close eye on future forecasts as confidence continues to increase.
On to the spaghetti:
So what exactly are spaghetti plots? Spaghetti plots are what meteorologists refer to when multiple numerical weather models are shown together. This creates a spaghetti like appearance because the individual model tracks are all plotted on the same image. These plots are important because they can give some insight into where a tropical system may track.
Here is the latest spaghetti plot for the remnants of Tropical Storm Harvey that’s heading towards the Gulf of Mexico. The 12Z guidance is clustering a landfall along the mid-Texas coast. This is a drastic shift northeastward over the past 24 hours. Guidance will continue to need to be assessed to determine if future shifts (northward or southward) are possible.
If you live along the Texas coast, you need to prepare now for potential tropical cyclone impacts. This is a precautionary measure in case impacts are felt late in the week. The other Gulf States should keep a close eye on this system, too, because it is possible it may phase and get pulled into Louisiana and Mississippi.