Hey all, I was going to wait to post this tomorrow morning with the forecast, but I figured, why wait? So here is a look into the Tropics right now and everything that I know and all the possible information meteorologists have to offer.
From the NHC
A broad area of low pressure is expected to form a couple of hundred miles south of the coasts of southern Mexico and Guatemala during the next day or two. Environmental conditions appear favorable for some gradual development thereafter, and a tropical depression could form this weekend while the system drifts generally northward. Regardless of development, heavy rainfall could occur over portions of Central America and southern Mexico late this week and into the weekend. See products from your local meteorological service for more information.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…medium…40 percent.
A broad trough of low pressure has developed over the southwestern Caribbean Sea associated with a westward-moving tropical wave. However, significant development of this system is not expected while the disturbance moves west-northwestward over Central America during the next couple of days. Regardless, this system could produce heavy rainfall across northern Colombia and portions of Central America from Honduras southward late this week and over the weekend. See products from your local meteorological service for more information.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…low…near 0 percent.
Tropical Elaboration
I grabbed two water vapor maps from the College of DuPage Meteorology page. These GOES-16 maps shows a handful of atmospheric features that will play a role in the development and movement of whatever develops in the tropics during the next 10 days.
The above map IDs two areas of interest and two areas of mid-level low pressure and one area of mid-level high pressure. Ont he below map those are ID’d.
Area of Interest in the Atlantic (1), Area of Interest in the Pacific (2), the mid-level low pressure in the Gulf (3) and the ridge of high pressure in the southwestern US (4) are all doing a gigantic atmospheric dance right now – and will continue to do so – during the next 72 to 120 hours.
The Inter-Tropical Convergence Zone (ITCZ) continues to shove showers and storms across the Tropical Atlantic. These waves of storms should start to congeal a bit down near Honduras and Nicaragua (1). At the same time, a different wave in the Pacific (2) will start to get better organized, too.
The little yellow squiggly line is where the flow from the ITCZ is meeting up with the mountains of southern Mexico and the mid-level flow around the ridge of high pressure to the north. That convergence is going to end within about 72 hours as the ridge lifts northward and pulls away from the area.
This is going to open the door for those clusters of storms to also lift north into the Bay of Campeche. That is where the mid-level area of low pressure (3) is currently spinning. That little mid-level vorticy is expected to diminish during the next 12 to 24 hours and will likely clear the deck for slamer conditions and lower shear to prevail in the area.
However, if there is any lingering spin in the atmosphere when the little cluster of storms lifts north into the Gulf, there may be some unexpected interactions between the two. Remains to be seen. But I will say, I think that is where some of the model guidance is trying to pick up on a system in the Gulf within 72 hours. It sees a lingering area of spin, a cluster of storms, and low shear and goes “LEERROOYY JEENKKIINZZZ!!” and makes a (weak) tropical system out of it.
Instead, a more likely scenario is one that may spill the area of interest in the Pacific (2) into the Gulf and spin that up into some sort of tropical system. This happened last year. Yuo may recall that Cristobal started as Amanda in the Pacific.
And looking back through history, tropical systems that form in this region, tend to lift northward.
That doesn’t guarantee that something will develop and it will move north, but history is always a good guide. While I think looking at the latest guidance is important, I think history is, too.
Model Guidance
Just a quick peek here. Not much.
Here is a look at what the European ensembles think the atmosphere will look like on Tuesday morning, next week.
If this pattern holds true, whatever may be out there may be in a space where there isn’t much of a steering current (stop me if you’ve heard this one before!) and so the direction the system goes will be dictated by more local atmospheric conditions than big picture stuff.
On top of that, since this isn’t shown very well within the modeling at this point, there is still some legitimate question about if anything ever actually develops.
The Bottom Line
We don’t know much at this point. Truly. And what we do konw is based on a bunch of “if this happens, then that happens” type of statements where we have to assume “if” something happens a next event will occur.
And, as you can imagine, that isn’t a very good basis for an accurate forecast.
That goes for all of the modeling out there right now, too. I could post a handful of different comptuer weather model outputs that show Cate 1 or Cat 2 Hurricanes in the Gulf. Or other model data that shows – literally – nothing in the Gulf.
But that doesn’t help anyone. Because the models aren’t very accurate right now.
In fact, I would go as far as to say that showing any deterministic model map with some tropical system at “X” spot at a certain time or “Y” landfall isn’t even useful information for anyone in the public. And I know these maps are already popping up on social media with people saying things like, “Just a model, but it could happen!”
But, it won’t. So, if I were you guys, I’d just ignore those things (unless you just want to look for fun). At this point, no deterministic model data is adding any value to the conversation.
All of that said… This is a GREAT reminder to make sure your Hurricane Preparedness Kit is ready to go and stocked up. Have you bought water for this summer yet? Canned food? Have your NOAA Weather Radio with batteries ready to go? All good things to think about!
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