TS Chantal Strengthened Some While We Slept... Who Should Worry?

First real visible of the day shows more questions than it answers. The ULL moving towards FL is carrying a lot of moisture wrapped up in it...which had been a concern last week in the forecast and then discarded as a problem ... but it can be a problem in two ways. More rain for FL at the SURFACE not just an ULL and as a steering factor in the tropics with regard to Chantal.



My much loved Water Vapor Loop below and in motion:



Going with this loop to illustrate a few things about Chantal and across the basin.

One question that stands out is.... Where is the High? What is happening to the High? What will happen?

Also, you can see clearly how Chantal ramped up last night from minimal borderline storm to a contender.

And, note the dance going on between the ULL moving towards FL and the approaching frontal boundary. Note that in about five days that same dance may repeat with a second frontal boundary now lingering from El Paso to Nebraska and Tropical Storm Chantal.

What I love about this "old school' loop is you can stop it...start it, compare it sometimes in a more simplistic way than others.

12 Hours Ago:

Current:

Look how much more defined Tropical Storm Chantal is...

Also notice how much moisture has increased in the area of the ULL in the Bahamas.

The "front" also looks a little weaker I may add... yet next week's front is forecast to be stronger.

Stronger LATER in July than EARLIER in July.

So many odd questions for this storm this year...odd to have a storm in early July in the Central Atlantic.

Also, odd to have strong frontal boundaries draped across the SE coast in early July like strands of pearls.

Now we have the "cones" that show the forecasted track... starting with the Navy Site which I prefer often.

Looking close up at this storm we see a very well defined center of circulation streaming along westbound at a fast clip. Nothing seems to bother this storm and that bothers me. She was born in a region where Saharan Dust was strong and it was forecast that the dust would eat up the moisture and she would die out..a footnote in our memories "wetting up the atmosphere" for future waves. That is how we usually view these early waves. They are sacrificed like Mayan maidens to the Gods of the Tropics to satisfy Cousin SAL and work their moisture into the shield of Saharan Dust that blankets that part of the world in early July. After a few of these sacrificial waves.... one good wave is able to make it close to the islands. Often, because of the poor conditions at birth, based on SAL depriving it of the proper nutrients, the storm struggles to stay together and has problems being aligned. 

This does not usually happen. But, it happened and suddenly Chantal is moving towards our part of the world not recurving gracefully up into the Atlantic like we would expect from an early July Cape Verde Wave storm. Chantal may go on record as born in the "Central Atlantic" but it was conceived in the Cape Verde Islands as it departed the coast of Africa catching our attention and the attention of the models.

Hey, at least we know the models are working this year...

My question on the track above is two fold.

1. Is the timing correct.

2. Is the intensity correct.

You cannot mess up an intensity forecast and the timing and have the end result work out the way you forecast. So, that's important.

Where is the shear that was forecast to kill Chantal before she became Chantal?

And, remember that models do take into consideration all other storms before it and in general "climo" and this storm is out of the box when it comes to climo. It bothered me last night that many forecasters want to write this storm off as a "novelty" when it is not a "novelty" it is the flavor of the week and no other flavors are being offered at the old Tropical Ice Cream Shop.  This is the storm that is on the plate and we need to deal with it. Easy to say it's minimal and not much to talk on and how it may fall apart down the road when it gets into the Bahamas near Florida ...after going through Haiti and or Cuba. Why? Because it may not do that... it's too early to tell. I'd like to get that Gulfstream Jet out there right now, more than Recon. We will have very good radar and satellite imagery really soon, as well as ship reports and direct reports from the islands near Barbados. What's up the road in the atmosphere is what I want to know.

"THE INTENSITY ESTIMATE IS HELD AT 35 KT FOR THIS

ADVISORY.  THE VERTICAL SHEAR OVER THE AREA IS NOT STRONG AT THIS
TIME...BUT THE SHIPS MODEL INDICATES THAT WESTERLY SHEAR WILL
INCREASE IN 1-2 DAYS.  ALSO...CLIMATOLOGY SUGGESTS THAT TROPICAL
CYCLONES THAT MOVE RAPIDLY WESTWARD OR WEST-NORTHWESTWARD IN THE
DEEP TROPICS HAVE DIFFICULTY STRENGTHENING. "

The discussion at 5AM shows this "ho hum" attitude towards the storm with an over reliance on climo and an eventual track over Haiti to break this storm up the way you would bat away a mosquito before killing it later when it gets closer. 

I am not saying it is not possible, it is. I am saying that if you relied on CLIMO...this storm would not be here. And, I disagree that it looks weak...it looks quite good for a minimal Tropical Storm that came together quickly last night. It seems if anything..."steady" and almost too reliable. 

AT 0900Z THE CENTER OF TROPICAL STORM CHANTAL WAS LOCATED NEAR      
LATITUDE 10.4 NORTH...LONGITUDE 49.5 WEST WITH MAXIMUM SUSTAINED    
WINDS NEAR 35 KTS...40 MPH...65 KM/H.  

8AM Advisory:

SUMMARY OF 800 AM AST...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...10.6N 50.6W
ABOUT 630 MI...1010 KM ESE OF BARBADOS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 26 MPH...43 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES

Note it only moved .2 degrees North since the last advisory... 

The basics with this storm are as such....   multiple factors up stream will decide what Chantal does and the only real card Chantal has to play is her own intensity as the stronger she gets she can affect her environment, the weaker she stays the less she can control her destiny. Also, her position will tell the real story down the road. The cone is wide in the beginning. She can be according to the NHC cone as far West as Central Cuba near Havana or it can be as far East as the Central Bahamas. It can be going WNW across Cuba or it can be going NNW through the Bahamas. It could be off the Central Coast of Florida moving North just as easily as westbound across Cuba and there is no guarantee it tangles with the tallest mountains in Haiti just yet. It can clip Gitmo and barely burp and be moving NW towards Miami just as easily. This is far from a slam dunk and not a storm to call a novelty by any means. In retrospect we can call it anything we want from a deadly storm that came in stronger than expected or a  powder puff light weight. It is dangerous for any forecaster to downplay a storm that is in strengthening mode as it moves towards the land...any land...even little islands in the Antilles.

This is your classic Cape Verde storm that forms in the Central Atlantic and moves towards the Caribbean and possibly the SE coast in the longer term with a side chance of making the Gulf (extrapolate the 3 day WNW across Cuba) or making a run towards the Outer Banks north bound over the very warm Gulf stream. With an out of the box storm like this, you can't rely on Climo and you can't rely on early models. 

This is your typical... the front dipping down and the high building in and if it goes over land with high mountains and there will be shear coming across Florida as the cold front dips down that can weaken the storm and steering currents could just bomb out and leave it adrift spinning up over warm water somewhere. 

Note that the High that has been reliably there is being worn away today by the ULL moving towards Florida and looking "odd" which worries me. It is "out of place" and anything "odd" bears watching.

Again is the intensity forecast off? Is it low? Is it spot on?

Is the timing right? The timing takes into consideration that she begins to slow down . . .

Will Chantal be somewhere near Florida on Friday or Thursday or will it be more like Saturday? 

Too many questions. 

Let's look at the NHC 3 day which is VERY reliable.

This is pretty much a "for sure" safe bet. Anything after that is too far away to rely on. And, at the moment the track is not over the highest mountains in Haiti. And, if the timing is a bit off and the storm has stayed to the "left" of the forecasted track they will drag the cone a drop to the south and Haiti isn't in play as much and we have a different ball game.

If she stays to the south of Haiti for the time being or curves faster she avoids shear. The shear is the winds around the ULL moving towards FL along with normal East Caribbean shear for July.

So, who should worry? Everyone in the Atlantic Basin for now... 

The Islands.

Haiti/DR

Cuba

Bahamas

FLORIDA

Carolinas

Maybe even Gulf of Mexico if the front weakens and it it goes further west...

What we do know...the models are not in love with it or more correctly the models that we love the most are not in love with it...  until or unless they fall in love with it the NHC will continue to be conservative and be in a watch and wait mode to see what Chantal does in relation to the models and they will be looking for any good model that breaks from the pack.

As for me.. I'm watching Chantal. I have a lot of interests in it's way... cousins on a cruise, kids and my mother in Florida, a daughter traveling from FL to NC on Thursday and .. me in NC so you can bet I'm watching.

Besos Bobbi.

Ps...

NHC bottom line:

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* BARBADOS
* DOMINICA
* SAINT LUCIA
* MARTINIQUE
* GUADELOUPE

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* SAINT VINCENT

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN 
24 TO 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE SOMEWHERE IN THE WATCH AREA...IN THIS CASE WITHIN 24 HOURS.

INTERESTS ELSEWHERE IN THE EASTERN CARIBBEAN SHOULD MONITOR THE
PROGRESS OF CHANTAL.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.