Tropical Depression LORENZO: Discussions & Images

[americanrebel]

The novice also called it a Hurricane. Looking at the radar it is now moving NW

[jeff]

We may come close to a distinct eye. There are some signs (on IR) of a warm depression attempting to form near the convective "towers" in the CDO's center. I think it's safe to utilize "rapid intensification" here. I think frictional effects will prevent intensification beyond Category 2 status, but the excellent ventilation (via UL anticyclone and 5 kts of shear) + heat content = deepening trend until landfall.

Last GOES visible imagery before night

I just looked at this animation and it shows it growing bigger in each frame... but I see no spin. Why does this one not have the same spinning look that the others in the past few weeks have
had ?

If a visible were available you would see some spin of the low clouds...you are seeing the expanding tops of thunderstorms on the IR images...there is rotation below just not very visible without the visible images.

[jeff]

We may come close to a distinct eye. There are some signs (on IR) of a warm depression attempting to form near the convective "towers" in the CDO's center. I think it's safe to utilize "rapid intensification" here. I think frictional effects will prevent intensification beyond Category 2 status, but the excellent ventilation (via UL anticyclone and 5 kts of shear) + heat content = deepening trend until landfall.

Last GOES visible imagery before night

I just looked at this animation and it shows it growing bigger in each frame... but I see no spin. Why does this one not have the same spinning look that the others in the past few weeks have
had ?

If a visible were available you would see some spin of the low clouds...you are seeing the expanding tops of thunderstorms on the IR images...there is rotation below just not very visible without the visible images.

Alvarda, MX radar clearly shows the "eye"...ir the low level circulation. I did not find a loop feature but if there were one you would see good rotation.

Getting very close to the coast now..maybe 40-50 miles offshore...still could intensify another 5-15mph before landfall given latest convective burst and slow forward motion.

[HURAKAN]

"Eye-catching" radar image!!!

[btangy]

I have a question for the professionals and others on this excellent board. Can a developing outer band (associated with decent low-level convergence) signify the beginning of a RI event? On WV imagery, you can see the convective band developing NW of Lorenzo "in sync" with the storm's quick pre-landfall deepening trend. I have seen this trend with Charley and numerous other storms (especially compact systems) when a fast strengthening trend started to run its course.

http://www.ssd.noaa.gov/goes/flt/t4/loop-wv.html

By the way, props to those (amateur, professional, and others) who stated the possibility for intensification to a hurricane before MX landfall. Good job, wxman57 and others!

When I was watching Humberto, I noticed one MCV basically took over and became the hurricane itself. I suspect something similar happened with Lorenzo. Usually you have multiple MCVs competing and rotating around a common center in developing tropical depressions and storms, so something fundamentally different is occurring at the mesoscale, and I don't think the research community really understands it yet. We know hurricane eyewalls are quite frontogenic meaning that gradients in pressure/moist energy can become very large very quickly, but I can't immediately answer why small core systems have a tendency to respond so quickly sometimes (but not always!). One would think that the surface fluxes are confined over a smaller area and the opposite should actually occur. Anyway, interesting problem, and one that deserves further exploration.

[Matt-hurricanewatcher]

Based on a clear and closed eye wall on a Mexican radar. I'm very impressed with this system, it may already be 85-90 knots if the radar sig has anything to say about it.

[CrazyC83]

Based on a clear and closed eye wall on a Mexican radar. I'm very impressed with this system, it may already be 85-90 knots if the radar sig has anything to say about it.

I'm not sure about that much, although it is hard to say due to lack of reliable data available. I'd estimate 70 kt right now, but I could be off some.

[americanrebel]

So you are saying there could be 2 Cat 2 instead of 2 Cat 1 in the post season analysis. Humberto and Lorenzo.

[Matt-hurricanewatcher]

"if" its still going through the IRC my numbers may not be wrong. I can't wait intill the recon gets in there.

[Tampa Bay Hurricane]

***NOT OFFICIAL!!!!*****

Rapid intensification over high heat content
waters and low shear, also a tight inner core,
land interaction the only inhibiting factor.
I think this will make landfall
with winds near 100 mph as a category 2.

[Matt-hurricanewatcher]

So you are saying there could be 2 Cat 2 instead of 2 Cat 1 in the post season analysis. Humberto and Lorenzo.

Its possible humberto could be upgraded to a 85 knot cat2 in post season. Based on the eyewall drop of 83 knots. In a few other things.

This we will have to see.

[HURAKAN]

[CrazyC83]

So you are saying there could be 2 Cat 2 instead of 2 Cat 1 in the post season analysis. Humberto and Lorenzo.

Its possible humberto could be upgraded to a 85 knot cat2 in post season. Based on the eyewall drop of 83 knots. In a few other things.

This we will have to see.

Humberto had conflicting signals, although I think 80 kt was the correct landfall intensity personally, I wouldn't be totally shocked to see it upgraded to Cat 2.

The next Lorenzo mission should be exciting...(unless you are in the landfall area). At least they had some time to prepare as it strengthened in daylight, but the flooding could be really bad.

[Tampa Bay Hurricane]

Super explosive intensification is happening over that white tiny Super Nova CORE!!!

[lrak]

it looks to be taking a ride up the coast. No Lorenzo says...I want the grand tour before my demise

[CrazyC83]

Any southerly wobbles will add even more strength to Lorenzo as well...just like with Humberto...

[txwatcher91]

When does recon get in Lorenzo?

[HURAKAN]

When does recon get in Lorenzo?

FLIGHT TWO --TEAL 74
A. 28/0600Z
B. AFXXX 0613A CYCLONE
C. 28/0230Z
D. 20.1N 96.7W
E. 28/0500Z TO 28/0900Z
F. SFC TO 10,000 FT

2 AM EDT

[HURAKAN]

FLIGHT TWO --TEAL 74
A. 28/0600Z
B. AFXXX 0613A CYCLONE
C. 28/0230Z
D. 20.1N 96.7W
E. 28/0500Z TO 28/0900Z
F. SFC TO 10,000 FT


Plane leaves at 1030 PM EDT.

[txwatcher91]

When does recon get in Lorenzo?

FLIGHT TWO --TEAL 74
A. 28/0600Z
B. AFXXX 0613A CYCLONE
C. 28/0230Z
D. 20.1N 96.7W
E. 28/0500Z TO 28/0900Z
F. SFC TO 10,000 FT

2 AM EDT

Thanks. It looks like they will find an intensifying Cat 2.