ATL: Tropical Storm Cristobal in North Atlantic

[funster]

Closed circulation with heavy convection near the center on Jacksonville radar. Looks like a TD to me now. In what way isn't it a TD?

Yes, it as a defined circulation, but organized convection over the center is not happening. The only place significant convection is occurring is on the eastern and southeastern sections of the circulation. It's not quite enough to be classified as a depression.

You don't need convection all the way around to be named. You just a center and strong enough winds in one quadrant.

[senorpepr]

Closed circulation with heavy convection near the center on Jacksonville radar. Looks like a TD to me now. In what way isn't it a TD?

Yes, it as a defined circulation, but organized convection over the center is not happening. The only place significant convection is occurring is on the eastern and southeastern sections of the circulation. It's not quite enough to be classified as a depression.

But visible and IR shows the circulation covered, and there have been many TD's with exposed LLC's which this one doesn't have.

Well, looking at the VIS and IR imagery off of NRL and meshing that with surface and buoy observations, and the LLC is not quite covered at all.

[senorpepr]

IMO, they should have sent the NOAA plane out there today...

You can't schedule a mission that quickly.

[Brent]

Closed circulation with heavy convection near the center on Jacksonville radar. Looks like a TD to me now. In what way isn't it a TD?

Yes, it as a defined circulation, but organized convection over the center is not happening. The only place significant convection is occurring is on the eastern and southeastern sections of the circulation. It's not quite enough to be classified as a depression.

But visible and IR shows the circulation covered, and there have been many TD's with exposed LLC's which this one doesn't have.

Yes I've seen MUCH worse looking TD's before.

[senorpepr]

Closed circulation with heavy convection near the center on Jacksonville radar. Looks like a TD to me now. In what way isn't it a TD?

Yes, it as a defined circulation, but organized convection over the center is not happening. The only place significant convection is occurring is on the eastern and southeastern sections of the circulation. It's not quite enough to be classified as a depression.

You don't need convection all the way around to be named. You just a center and strong enough winds in one quadrant.

Then where are the winds? The highest wind report is 20KT. Dvorak only supports 25KT. There's just not enough evidence to upgrade at this time and no justification to send recon in at this time.

[txwatcher91]

How can you say the center is exposed when 10minute old visible shows the circulation completely covered, unless the center is over land. TD's dont't have to have 30kt winds, I have seen some at 20 and 25 before.

[Ed Mahmoud]

Just watched JB's update. Half of a 10 minute video about why the NHC should be calling this 94L a TD since yesterday, and some more on how he got the Southeast system when nobody else did.

His cone of uncertainty on 94L issued to his better paying clients yesterday shows 94L becoming a hurricane just before the Yucatan, with a landfall between Tampico and Brownsville, with the usual uncertainty area up to near Corpus Christi-ish area.

96L is a strong tropical storm or maybe a hurricane Sunday/Monday in Hatteras, and may swing close enough to New England to effect weather Tuesday.


Don't want to give more info than that, lest I violate a terms of service agreeement, and I offer no commentary on whether JB is correct or not, and while I do recall a few significant errors he has made, I also recall he basically called last year's Humberto 2 or 3 days before anyone else.

[senorpepr]

Yes I've seen MUCH worse looking TD's before.

But usually there's some sort of supporting evidence for that upgrade. In this case, there's not. They won't upgrade a T1.0 without any observations supporting something higher.

[senorpepr]

How can you say the center is exposed when 10minute old visible shows the circulation completely covered, unless the center is over land. TD's dont't have to have 30kt winds, I have seen some at 20 and 25 before.

I never remember seeing an initial advisory for 20KT. Maybe a final, but never an initial. I agree, you might see 25, but in this case, there's nothing to justify that.

[txwatcher91]

How can you say the center is exposed when 10minute old visible shows the circulation completely covered, unless the center is over land. TD's dont't have to have 30kt winds, I have seen some at 20 and 25 before.

I never remember seeing an initial advisory for 20KT. Maybe a final, but never an initial. I agree, you might see 25, but in this case, there's nothing to justify that.

But doesn't the NHC's definition of a TD say that an LLC and convection over the center is all that is needed? How do you know there isn't a small band of 30kt winds, radar shows some 50kt about 6,000 feet above the surface and I am sure some of that is working its way to the surface in the stronger bands.

[Derek Ortt]

I think this could be classified as a 25KT depression, Mike

We have a closed center now with organized, albiet poorly, convection on the eastern semi-circle

that said... a 25KT depression is not something worth getting all worked up about

[curtadams]

I'll accept "winds aren't strong enough" as a reason not to upgrade. But if they need 25 kts for a TD, it should be part of the official definition.

[txwatcher91]

I'll accept "winds aren't strong enough" as a reason not to upgrade. But if they need 25 kts for a TD, it should be part of the official definition.

But isn't the definition a closed LLC and convection over the center for 24 or more hours?

[senorpepr]

I think this could be classified as a 25KT depression, Mike

We have a closed center now with organized, albiet poorly, convection on the eastern semi-circle

that said... a 25KT depression is not something worth getting all worked up about

I would agree, but I still don't see them actually upgrading it until either a) an observation better supports it or b) satellite pattern improves.

[txwatcher91]

I think this could be classified as a 25KT depression, Mike

We have a closed center now with organized, albiet poorly, convection on the eastern semi-circle

that said... a 25KT depression is not something worth getting all worked up about

I would agree, but I still don't see them actually upgrading it until either a) an observation better supports it or b) satellite pattern improves.

I don't see it being upgraded today, but the NHC can be inconsistent. However, I think one could argue that this is a TD right now, although a weak one.

[Brent]

that said... a 25KT depression is not something worth getting all worked up about

That's true.

[jasons2k]

Looking at the radar, to me it looks like we have a LLC, but further away (and the radar beam is higher) it looks like a MLC. The centers are not stacked yet, but they are getting closer. If one of the centers can take over then it can intensify, but it is still disorganized for now.

[fci]

Just watched JB's update. Half of a 10 minute video about why the NHC should be calling this 94L a TD since yesterday, and some more on how he got the Southeast system when nobody else did.

His cone of uncertainty on 94L issued to his better paying clients yesterday shows 94L becoming a hurricane just before the Yucatan, with a landfall between Tampico and Brownsville, with the usual uncertainty area up to near Corpus Christi-ish area.

96L is a strong tropical storm or maybe a hurricane Sunday/Monday in Hatteras, and may swing close enough to New England to effect weather Tuesday.


Don't want to give more info than that, lest I violate a terms of service agreeement, and I offer no commentary on whether JB is correct or not, and while I do recall a few significant errors he has made, I also recall he basically called last year's Humberto 2 or 3 days before anyone else.

Ed:
Thanks for sharing this info.
I WISH people would stop looking for "credit" when the do their job.
No one should doubt any Pro who has the credientials but always looking for "credit" is so annoying to me.
PLEASE do not interpret this as bashing JB. I respect his knowledge but just wish the "I called it" comments would stop.

[hiflyer]

Air traffic starting to avoid the area...radar indicates tops now above 30k though cessna jet went over at 38 and a spirit is climbing above 38 (airbus-he can't go much higher)....rest are transiting west or east...mostly onshore east. Sigmet below says tops to 45....that is getting up there fairly early which suggests this is getting it's act together.....

WSUS31 KKCI 181655
SIGE
CONVECTIVE SIGMET 40E
VALID UNTIL 1855Z
SC FL GA CSTL WTRS
FROM 90SE CHS-160SE CHS-160E OMN-90NE OMN-90SE CHS
AREA EMBD TS MOV LTL. TOPS TO FL450.

[cpdaman]

that said... a 25KT depression is not something worth getting all worked up about

That's true.

of course it's not , but in recent memory we have seen storms surprise to the upside