Tropical development is a possibility in the Gulf of Mexico next week.
Looking at the latest model guidance
The GFS is still predicting development, showing a tropical storm developing in the northeast Gulf by Thursday in its 00z run.
Meanwhile, the ECMWF is now predicting formation of a tropical storm in the northeast Gulf by late Thursday (see figure 1). This is a change from yesterday’s 00z run.
Ensemble support has also increased, with the ECMWF ensemble (EPS) members now predicting a 60 – 70 percent chance of a tropical depression forming in the northeast Gulf in the 5 – 7 day range.
Development not a guarantee
While there has been an overall increase in model support for Gulf development next week, development is far from certain.
At the time of yesterday’s update, the catalyst for development appeared to be a stalled, decaying front.
Last night’s ECMWF ops run carries vorticity associated w/ an ongoing Midwest MCV (thunderstorm complex), subtly blends it with a front sliding into the northern Gulf, and develops a tropical cyclone out of it. #flwx pic.twitter.com/nm85VbQ3JX
— Greg Postel (@GregPostel) July 5, 2019
However, it is now apparent the catalyst is actually an area of vorticity from a mesoscale convective system (MCS) currently over Missouri interacting with the front.
This adds more uncertainty, as MCS are small features, making them difficult to predict.
Ultimately, there are several different scenarios that could play out. If the vorticity from the MCS makes it to the Gulf and develops into a tropical cyclone (TC) as some model guidance suggests.
Alternately, the MCS vorticity could remain over land, which would result in no development.
Too early for specifics
It is too early to speculate things like track and intensity, as we don’t even know if a TC will form.
Although, it should be noted that:
- wind shear is currently low in the northeast Gulf per an analysis from CIMSS, and model predicted to remain low;
- sea surface temperatures are anomalously warm, with actual temperatures between 30 and 31 degrees Celsius.
So, IF the MCS makes it over the Gulf, conditions could very well be favorable for development/intensification.
Nothing to stress over
At this time, this is nothing to worry about. The chance of development is still low due to the previously discussed uncertainties.
However, it continues to be something to keep an eye on this weekend going into next week.
