Wednesday, July 22, 2020

The Future-TS-Gonzalo and Gulf of Mexico Blobette: July 21, Update A

Oh finally, a little excitement! A new storm to watch. Things were getting quite boring otherwise.... 

The Future-TS-Gonzalo
The Future-TS-Gonzalo was finally upgraded to Tropical Depression 7 today, which means he has closed circulation and winds under 38mph. I think this chap is already a Tropical Storm - he has a pretty good circulation (vorticity) signal through the entire lower half of the troposphere (see the <Science Alert!> post here to find out about the troposphere), and the NHC forecast shows that they think he'll be Gonzalo in the next few hours. 

The current center is around 10N, 41.3W, heading WNW at 9mph, which takes him into the Caribbean by Saturday:
 
For now, I agree with this southerly track as the pressure fields are strong enough to keep him to the south. Actually, at the moment it looks like this one may stay to the south -  heading towards central America or the Yucatan.

He is in an area of low wind shear which will allow him to grow (hence, we will officially have TS Gonzalo tomorrow). However, he is skirting the southern edge of the Saharan Air Layer, as you can see in this map, which tends to inhibit storm development. 


I know you've all heard about the Saharan Dust by now, but just in case it got lost in the Great News Cycle of 2020, methinks it's time for a new <Science Alert and Forecasting Alert!>. The excitement just keeps on rolling in! :-)

<Science Alert and Forecasting Alert!> The dust that comes off northern Africa quite often (not always!) travels westward across the Atlantic towards the Caribbean and Florida, amongst other places. This is called the Saharan Air Layer (SAL).

The SAL has two major impacts. The good one (especially if you are writing a hurricane blog in your 'spare time') is that it tends to suppress tropical storms; in particular it impacts their ability to get their convection groove on. The bad impact is that, amazingly, it carries microbes and stuff (technical term for 'stuff' ;-)) across thousands of miles, and these have been known to increase health issues along the western side of the Atlantic - especially respiratory illnesses. Just what we need this year, hey? 

In the satellite image above, the red and yellow bits are the dust levels. Red indicates areas where you'll need an industrial strength vacuum cleaner to suck up all the dust, and yellow areas are places where a feather duster used daily might work ;-). You can see our friend, the Future-TS-Gonzalo, at around 10N, 41W just on the southern edge of the dust. 

This image is from the University of Wisconsin CMISS page, which is an excellent website for this sort of handy dandy information! 

Go to http://tropic.ssec.wisc.edu/tropic.php if you want to look for yourself (and I'm sure you all do!! :-)). Click on the colour block in the lower map (Regional Real-Time Products) for the part of the world you are interested in (North Atlantic in this case), and in the drop-down menu (amongst a number of other things that I'll cover in future updates), you will see 'Saharan Air Layer Analysis'. Click on the Saharan Air Layer and you will see the map above. Easy peasy! Now you are all experts in the SAL! Ta-da. :-) <End Science and Forecasting Alert!>

Here's the infrared satellite image of the tropical North Atlantic. And the Caribbean. Ok, and a bunch of the Gulf of Mexico. 
You can see the Future-TS-Gonzalo - he's the red splodge (technical term ;-)) that looks like it's got some circulation. What's cool about this image is that you can also the train of clouds across the entire Atlantic, skirting the edge of the SAL.

Gulf of Mexico Blobette
What is also interesting about this image is that you can see why they got the yellow crayon out to draw an 'x' in the Gulf of Mexico:
It's a little too far into the Gulf according the that cross, but the convection is fairly weak and there isn't much well-organized circulation at the moment, so it is a little difficult to see where it really is. It currently has a 30% chance of developing in the next 48 hours. It's been loitering over this area since yesterday though, so I expect Cuba and parts of Florida are a little soggy.

Next name on the agenda will be Hanna. 

That's it for today my peeps. Time for a few more slurps of Bordeaux and to make sure Dust Buffy (our adopted outdoor dust-coloured kitty) has been fed and watered. (I wanted to call her Dust Bunny, but that's a different story.)
 
Toodles, 
J.

Twitter: jyovianstorm
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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and local weather service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know. 
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