Invest 91L E Windwards,Comments,Sat Pics,Models Thread #2

[Matt-hurricanewatcher]

It has a closed LLC in when the recon gets out there in finds it so it will be upgraded any way. But if you went it upgraded at 11pm it has to keep forming convection.

[Damar91]

But I thought the season was over? I'm sorry, just had to.

[Thunder44]

It has a closed LLC in when the recon gets out there in finds it so it will be upgraded any way. But if you went it upgraded at 11pm it has to keep forming convection.

I'm not sure it has a closed LLC. They LLC it had eariler this morning today dissapated.

[SouthFloridawx]

It has a closed LLC in when the recon gets out there in finds it so it will be upgraded any way. But if you went it upgraded at 11pm it has to keep forming convection.

I'm not sure it has a closed LLC. They LLC it had eariler this morning today dissapated.

I didn't hear about that, do you have a link? Thanks in advance.

[Dean4Storms]

That ball of convection had sort of a D shape to it earlier!

[Bailey1777]

Are you sure? There was a question as to if it opened but I never saw anything about it being gone.

[bvigal]

bvigal,here is a good site where you can get more rapidly the daily Plan of the day and the other links to the recon data.

http://www.hurricanehunters.com/wxdata.htm

Thanks, Luis!!
Let's hope that BAMM is wrong, huh?

[Thunder44]

It has a closed LLC in when the recon gets out there in finds it so it will be upgraded any way. But if you went it upgraded at 11pm it has to keep forming convection.

I'm not sure it has a closed LLC. They LLC it had eariler this morning today dissapated.

I didn't hear about that, do you have a link? Thanks in advance.

I was just looking QS pass this morning and visible images earlier I could not find a LLC. Also Derek said it didn't appear to have one either.

[Bailey1777]

So the low that the NHC claims is there is at what level?

[Thunder44]

So the low that the NHC claims is there is at what level?

It's a surface low, but not necessarily closed low.

[Extremeweatherguy]

So the low that the NHC claims is there is at what level?

It's a surface low, but not necessarily closed low.

Considering the NHC thinks it could develop as soon as tonight, I would bet that this probably is a closed LLC (or at least very close to it).

[sevenleft]

So the low that the NHC claims is there is at what level?

It's a surface low, but not necessarily closed low.

Ok...whats the difference between a surface low and a closed low?

[SouthFloridawx]

The circulation is going come pretty close to this bouy so we'll have to watch in the next 12-18 hours.
http://www.ndbc.noaa.gov/station_page.php?station=41040

[Weatherfreak14]

Looks better than it did midnite last night, I sure can tell you that. I just wonder if it will do the same tonite.

[Tampa Bay Hurricane]

So the low that the NHC claims is there is at what level?

It's a surface low, but not necessarily closed low.

Ok...whats the difference between a surface low and a closed low?

Here is what I think: A Pro-Meteorologist or someone with
knowledge please correct me if I am wrong:

Surface low is a low in the lower levels of the atmosphere...

A closed low is a low that has closed in on all sides...that is the
isobars of lower pressure surround it on all of its quadrants...
none of its quadrants and no segments of it are open to higher
pressure conditions outside the low.

A surface low is not necessarily a closed low...but I am not sure
about what exactly it is for 91L

[Wthrman13]

So the low that the NHC claims is there is at what level?

It's a surface low, but not necessarily closed low.

Ok...whats the difference between a surface low and a closed low?

Here is what I think: A Pro-Meteorologist or someone with
knowledge please correct me if I am wrong:

Surface low is a low in the lower levels of the atmosphere...

A closed low is a low that has closed in on all sides...that is the
isobars of lower pressure surround it on all of its quadrants...
none of its quadrants and no segments of it are open to higher
pressure conditions outside the low.

A surface low is not necessarily a closed low...but I am not sure
about what exactly it is for 91L

Not exactly, but pretty close. Technically when a meteorologist talks a bout a "low", it automatically is closed in the sense you are talking about, so a surface low IS a closed low by definition (in this sense). Your last sentence should be switched to say: "a closed low is not necessarily a surface low".

There is an additional caveat that a closed low in the pressure sense (i.e. having closed isobars), does not necessarily have a closed wind circulation with respect to the surface. This is why it can get really confusing when one is talking about a closed low. Do you mean closed in the sense of pressure, or closed in the sense of winds?

To clarify: a closed low is a low with at least on isobar of pressure (of arbitrary value) completely encircling the center.

See http://amsglossary.allenpress.com/gloss ... losed-low1

A surface low is a (closed) low at the surface.

[Bailey1777]

Buoy 41040 (approximately 250 NM. NW of 91L)

Wind-ENE
Wind Speed-15.5
Gust-17.5
Pressure-29.88

[bvigal]

Code: Select all

   DATE/TIME     LAT     LON    CLASSIFICATION        STORM
  08/1145 UTC    12.6N   46.7W    T1.5/1.5              91L
  07/1745 UTC    12.2N   41.9W    T1.0/1.0              91L
  07/1145 UTC    12.2N   40.5W    T1.0/1.0              91L
  07/0545 UTC    11.7N   38.2W    TOO WEAK              91L
  06/1745 UTC    11.7N   36.0W    T1.0/1.5              91L
  06/1145 UTC    12.0N   33.1W    T1.5/1.5              91L


These are the estimates issued so far on 91L
What determines at what intervals, or if at all, these are done? Are they simply arbitrary? I know sometimes they are also done at 23:45.

[sevenleft]

I just wanted to see what the explanation for them being different was from the poster who said they weren't the same thing....(which they are generally)

Since we are dealing with the tropics, surface winds tend to be the point of debate.

If you think 91L is/was open, then you could say it was a surface trough instead...

Surface low and closed low tend to be used interchangeably when talking about a closed low pressure wind circulation.

[Bailey1777]

Thanks for the feedback.