Saturday, June 04, 2016

Tropical Storm Bonnie and the Caribbean Blob: 3rd June, Update A

Didn't I *just* say that Tropical Storm Colin wasn't supposed to show up until July?!? Sigh. No-one listens. ;-)

I've had a few queries from the lovely but marginally concerned citizens of Florida today about the Caribbean Blob, so here's where we are ...

Caribbean Blob
He is over very warm water with sea surface temperatures of around 29-30 deg C (toasty) and the upper 100-125m of the water column is warmer than 26.5 deg C. This means that this blob has enough to produce a lot of rainfall, some heavy, thundery clouds, and generally look mean on satellite images. BUT, he is currently facing a lot of wind shear and has been all day (and looks like he will tomorrow), so he's a bit weak and not looking quite as well put together as he was earlier this morning (Friday, 3 June morning) as you can see in this satellite image... what do you mean, which blob is he? He's that one... you know... er... 

Yes, precisely - it's a bit of a mess down there. He's actually the blob at around 16N, 83.5W ish. 

The pressure patterns do currently show a path towards Florida. He could do a sharpish turn and just scoot over the Keys, or he could dilly dally and go and visit the Panhandle. He's too weak and it's too soon to say. For now, I'd remember the iconic words engraved on the cover of the Hitchhikers Guide to the Galaxy: "Don't Panic!" ;-) 

I think he won't be a whopping big hurricane because of the time and location of formation.

<Science Alert!> Ooh… first one of the year! Oh what a lucky day for you! ;-) It’s not unheard of to have storms this early and especially storms that pop up close to the coast and in the Caribbean or Gulf of Mexico, but the good news is that they are generally dinky little things that usually bring that much needed rain. Here is a figure that I made some years ago that shows the track of all storms from 1851 to 2005, divided into the month they formed/existed (graph credit: MOI!). 

In the early and latter parts of the season we have storms that develop in the western Atlantic/Gulf of Mexico/Caribbean region. But early in the season things are still warming up and because they are so close to land, they don’t usually have time to develop into anything major. During the peak months it’s another story! Storms develop in the eastern Atlantic and have lots of space and time (but no TARDIS, thankfully!) to get nice and strong before getting to land. This figure also shows why we have a ‘hurricane season’. 97% of all storms form between June 1 and Nov 30, with 78% forming during the peak months of Aug-Sept-Oct (stats from Landsea’s 1993 paper). But you can see that every so often we do get storms that develop outside of the season (including January - which is what we had this year with Hurricane Alex!). Not common, but definitely not impossible! <End Science Alert!> 

Tropical Storm Bonnie
Agh, she came back! She is barely a Tropical Storm with winds of 40mph (TS wind range: 39-73mph), central pressure 1006mb. She is located at 35.9N, 69.9W, heading east at 12mph. Not really a threat to anyone unless you are sailing in the middle of the Atlantic, in which case you may have noticed a bit of a bumpy ride. She has bits of convection, but is also in a region of wind shear so we can easily see the center of rotation in the satellite images:

Unless she does a U-turn and heads back to the coast, or actually get to land somewhere, I won't be saying anything more about Bonnie. 

I'll be back tomorrow evening!
Toodle Pips,

Blogs archived at
Twitter @JyovianStorm
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 the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.

No comments: