Good morning, everyone. As Invest 91L continue to churn around in the Bay of Campeche, the model guidance is starting to come into some agreement on the fate of the system.
Model guidance says…
Right now, the GFS and European model guidance shows Invest 91L drifting in a generally northerly direction toward Texas. Little to no development is anticipated from the system as it drifts along the Mexican coast to the north. However, what will happen is the moisture from Invest 91L will getting pulled north into a developing area of low pressure coming out of the Rockies on Thursday. By Friday and into Saturday, Invest 91L will drift north and meet up with whatever is coming out of the Rockies.
This will increase the rain potential for parts of the Gulf Coast. And that’s about it.
What’s the forecast?
Rain. Storms. Maybe some wind. This is truly looking like a low-end threat for Gulf Coast right now. How much rain? Well according to the smart folks at the Weather Prediction Center, between one-to-three inches of rain during the next seven days.
And given how dry the region has been (in some places) lately, that may be something our yards and gardens appreciate. The unfortunate part is that the heaviest of the rain will fall across parts of Arkansas, northern Mississippi and Alabama, and Tennessee and Kentucky. And then all of that water will flow down the already-swollen-and-flooding Mississippi River.
Is this locked in, or can it change?
It is by no means locked in. Honestly, and will full disclosure here, forecasts are very rarely “locked in” more than 12 hours out. And even then, there is some wiggle room. When it comes to tropical systems, I never like to use the term “locked in” or “guarantee” or “promise” because I’ve learned over the years that there is so much that we just don’t know yet about tropical systems.
Borrowing a line, “The most elementary and valuable statement in science, the beginning of wisdom is ‘I do not know’.”
And I do not know, for certain, what tropical systems are going to do beyond about 12 hours out. There are probabilities and confidence-intervals, sure. But nothing in the tropics is ever fully guaranteed.
Well, then, what could change?
Some things could change. The placement of the ridge, the speed of the system coming out of the Rockies are the two biggest factors for the forecast for the Gulf Coast. Given the available data, Rapid Intensification isn’t likely.
The SHIPS guidance is showing a 12-percent chance that it gains 25kts in wind speed during the next 24 hours. And a less-than-five-percent-chance that Invest 91L gains 55kts during the next 48 hours.
Despite any changes to the system itself, the overall threat will likely remain pretty similar to the forecast right now. Rain for the Gulf Coast. Maybe some wind, too.
But it bears monitoring during the next few days and we will – as always – let you know of any changes.
