The disturbance we have been tracking, now located in the Southeast U.S. (see figure 1), has a high chance of developing in the northern Gulf later this week.
Latest from the National Hurricane Center
Here is the latest from the National Hurricane Center as of the 8 AM EDT Tropical Weather Outlook:
A trough of low pressure located over central Georgia is forecast to move southward toward the northeastern Gulf of Mexico, where a broad area of low pressure is expected to form in a couple of days. Some gradual development is possible thereafter and a tropical depression is likely to form by the end of the week while the low meanders near the northern Gulf Coast. Regardless of development, this system has the potential to produce heavy rainfall along portions of the northern and eastern U.S. Gulf Coast later this week. For more information about the rainfall threat, please see products issued by your local weather forecast office and the NOAA Weather Prediction Center. Interests along the northern Gulf Coast and the Florida peninsula should monitor the progress of this system.
They have increased 5 day development odds to 80 percent.
Model guidance
All three of our top performing models for tropical cyclone (TC) genesis – the ECMWF, UKMET and GFS – were predicting tropical cyclone genesis in the northern Gulf later this week as of the 00z model cycle.
Track
There is a fairly substantial spread among the model guidance with regard to track.
The ECMWF is predicting a generally westward track across the Gulf, with landfall near Beaumont, TX late Saturday (see figure 2).
The GFS is mostly in agreement with the ECMWF, but has a different landfall location – near Corpus Christi, TX Saturday.
The UKMET has an entirely different track from the GFS and ECMWF, with a west track through Thursday, followed by a turn to the northwest/north, with landfall Saturday near Pascagoula, MS.
The GFS ensembles (GEFS) and ECMWF (EPS) ensembles have tracks ranging from the Florida Panhandle to the Texas Gulf Coast.
The reason for model variation with track is their forecast of the strength/position of an upper-level ridge. The ECMWF and GFS forecast this ridge to nose into the Southeast, forcing as west track. The UKMET does not.
Intensity
Just as they do with track, models also vary largely with respect to intensity.
Both the ECMWF and UKMET predict a strong tropical storm/minimal hurricane, while the GFS has a tropical depression/low end tropical storm at best.
It is worth noting that sea surface temperatures are in the 84 – 87 degree (F) range. Wind shear is also currently low in the Gulf (see figure 3), predicted to remain fairly low. So, the ECMWF and UKMET are not necessarily “out to lunch.”
As of now, it seems the how quickly development occurs and time over water could be the only limiting factor for intensity.
Impacts
With there still being such a large amount of uncertainty with track and intensity, impacts and placement of said impacts, are very much unknown.
Obviously with a weaker system, the main impact would be rain. With a stronger system, there could be issues with surge and wind.
Entire Gulf Coast should monitor
Everyone from Texas to Florida should monitor the progress of this system.
What should I do now?
Monitor the forecast and check your hurricane plan/kit.
