Dr. Jeff Masters' WunderBlog

There is an area of 850mb vorticity just east of Trinidad:


But, There is very little 500mb vorticity


Does anyone know what the lack of 500mb vorticity means?

Quoting MiamiHurricanes09:
Wow, very interesting. This is from that wave that should be emerging on Friday or this weekend, correct?

where will it be emerging??

Quoting weatherwatcher12:
There is an area of 850mb vorticity just east of Trinidad:


But, There is very little 500mb vorticity


Does anyone know what that means?

There is also a very pronounced eye, just north of the Great Lakes.
Well, willyalookat dat?? LOL

Baltimorebirds /bad

Quoting StormW:


If you take a trof, like we see over the U.S., or like a trof that steers a storm away, if you draw the axis, and it tilts forward, in the direction the trof is moving, then it is classified as a "positive tilt", usually indicating the trof hasn't reached it's full potential. A negative tilted trof, has the axis pointing in the opposite way, or backward (as in a N-S direction, it would tilt from SE-NW) and is an indication of a maturing trof.

In a tropical wave, it is opposite, because with the inverted "V" signature, it is like an inverted trof.

so how woulod you know if it was a maturing trof or a tropical wave??

Quoting Levi32:


Sorry should have clarified, the top part, the northern end. For a longwave trough over the US it would be the southern end, but tropical waves are inverted troughs. It is whichever end of the trough is pointing towards high pressure, which for a tropical wave is the north end (Bermuda High to the north)

Ahh, thanks!

dinner? red vines....

Quoting pottery:

There is also a very pronounced eye, just north of the Great Lakes.
Well, willyalookat dat?? LOL

I thought he was talking about the yellow circle you've been complaining about.

Quoting Levi32:


A negatively-tilted wave, which StormW just described in case you need clarification, results in more surface convergence because the wave axis is pointing forwards into the flow, instead of backwards. This is like a trough digging in over the eastern United States in the winter. When they become negatively tilted, they are stronger and usually result in a bad winter storm for the eastern seaboard. This doesn't mean a negatively-tilted tropical wave will develop, but it usually means that the wave is vigorous and there is good convergence going on along the axis.

For those who may still be a little fuzzy on this, think of it like a stick. When you hold one end of the stick and place the other end on the ground, it is encountering higher pressure (like the north end of a tropical wave axis pointing into the Bermuda High). Now try dragging that end of the stick along the ground while applying some pressure. If you're dragging it behind you with the end that's touching the ground pointing back in the direction from which you came, then it's pretty easy to drag it along the ground. But if you now hold the stick pointing in front of you in the direction you are trying to go, with the end in the ground and try to push, it becomes very hard, and the stick will try to dig up some of the dirt underneath it.

This is very much like what happens with negatively-tilted troughs. Positively-tilted troughs can be thought of as getting "dragged" through the air flow, and thus there is little convergence because it is pretty easy to drag that stick when it's pointing behind you. If the trough becomes negatively-tilted, its axis is pointing into the high pressure (the ground) out in front of you, and that stick becomes harder to push and causes fierce resistence along it. For a trough, this resistance causes strong convergence along the axis which forces air to rise, much like the stick in the ground starts digging up dirt as you push it.

If that made no sense at all, I apologize.

God bless you Levi!

Quoting NRAamy:
dinner? red vines....

sounds like some mad hippy whole food. Unless those vines have little purple orbs hanging in bunches and desirous of being transmogrified into liquids.
In which case, Purple Orbs for Purple Hippo.
Sounds good!

Quoting Levi32:


For those who may still be a little fuzzy on this, think of it like a stick. When you hold one end of the stick and place the other end on the ground, it is encountering higher pressure (like the north end of a tropical wave axis pointing into the Bermuda High). Now try dragging that end of the stick along the ground while applying some pressure. If you're dragging it behind you with the end that's touching the ground pointing back in the direction from which you came, then it's pretty easy to drag it along the ground. But if you now hold the stick pointing in front of you in the direction you are trying to go, with the end in the ground and try to push, it becomes very hard, and the stick will try to dig up some of the dirt underneath it.

This is very much like what happens with negatively-tilted troughs. Positively-tilted troughs can be thought of as getting "dragged" through the air flow, and thus there is little convergence because it is pretty easy to drag that stick when it's pointing behind you. If the trough becomes negatively-tilted, its axis is pointing into the high pressure (the ground) out in front of you, and that stick becomes harder to push and causes fierce resistence along it. For a trough, this resistance causes strong convergence along the axis which forces air to rise, much like the stick in the ground starts digging up dirt as you push it.

If that made no sense at all, I apologize.

yeah, but the last line was priceless! XD

New shear maps are out, there is an anticyclone in South America moving north

Levi, post #2311 -great analogy!!

Quoting Baltimorebirds:
Some guy I heard you don't want to know.He is the other infamous blogger besides JFV.He has be sited by other bloggers as a troll/know it all.

oh man you def. dont want to know JFV.

Quoting Levi32:


For those who may still be a little fuzzy on this, think of it like a stick. When you hold one end of the stick and place the other end on the ground, it is encountering higher pressure (like the north end of a tropical wave axis pointing into the Bermuda High). Now try dragging that end of the stick along the ground while applying some pressure. If you're dragging it behind you with the end that's touching the ground pointing back in the direction from which you came, then it's pretty easy to drag it along the ground. But if you now hold the stick pointing in front of you in the direction you are trying to go, with the end in the ground and try to push, it becomes very hard, and the stick will try to dig up some of the dirt underneath it.

This is very much like what happens with negatively-tilted troughs. Positively-tilted troughs can be thought of as getting "dragged" through the air flow, and thus there is little convergence because it is pretty easy to drag that stick when it's pointing behind you. If the trough becomes negatively-tilted, its axis is pointing into the high pressure (the ground) out in front of you, and that stick becomes harder to push and causes fierce resistence along it. For a trough, this resistance causes strong convergence along the axis which forces air to rise, much like the stick in the ground starts digging up dirt as you push it.

If that made no sense at all, I apologize.

Good analogy but the stick is upside down? The drag on the storm would be winds (sheer) at the upper level?

Quoting ShenValleyFlyFish:


I thought he was talking about the yellow circle you've been complaining about.

He was, actually. And I seem to have spoiled the question he asked. Which was a good one too.

"why that difference in the vort between 850 and 500" ??

Pottery...

I was thinking of you and your flight earlier while looking at the satellite images. I figured you would be ready for a "double" when you got home this evening!

CRS

CHEERS! CRS.
:)

Quoting ShenValleyFlyFish:


Good analogy but the stick is upside down? The drag on the storm would be winds (sheer) at the upper level?

The dimensions of the visual image were not supposed to be perfect. For a tropical wave, the ground would be in a northerly direction, the Bermuda High north of the wave axis.

Hello pottery
Rain,rain and more rain,we need it but its hampering my work,6 inches in 9 days.I guess we'll have around 20 by the end of the month.

Quoting Hurricanes101:
New shear maps are out, there is an anticyclone in South America moving north

Link please.

Quoting pottery:

He was, actually. And I seem to have spoiled the question he asked. Which was a good one too.

"why that difference in the vort between 850 and 500" ??

The wave is strongest in the low-levels, from the surface to 850mb, and then becomes progressively weaker as you go above that. It is weaker at 700mb and weaker still at 500mb. This happens a lot after a tropical wave has passed the point on its journey west where the AEJ ceases to exist (it only extends a little way out into the eastern Atlantic).

Circulation on the increase. We might have an invest within 48 hours, all we need is consistency to have an invest.

12z - 18z coming out soon.

How was your trip to our sister isle?

Quoting Hurricanes101:
Shear map

Thanks!

Quoting Hurricanes101:
New shear maps are out, there is an anticyclone in South America moving north

By 36 hours that anticyclone provides much lighter winds over the wave.

Weak anticyclone should be placed aloft to this area of showers and thunderstorms over the Antilles. Any signs of a closed low at the surface, actually let me rephrase that, any signs of a surface low?

Quoting Levi32:


By 36 hours that anticyclone provides much lighter winds over the wave.

Correct.

Quoting DDR:
Hello pottery
Rain,rain and more rain,we need it but its hampering my work,6 inches in 9 days.I guess we'll have around 20 by the end of the month.

WOW! I have had a touch over 5" in that timespan. But 3+" fell today!

18z GFS 180 hours: A royal mess around central America in both ocean basins:

Quoting Levi32:


The wave is strongest in the low-levels, from the surface to 850mb, and then becomes progressively weaker as you go above that. It is weaker at 700mb and weaker still at 500mb. This happens a lot after a tropical wave has passed the point on its journey west where the AEJ ceases to exist (it only extends a little way out into the eastern Atlantic).

Nice! Thanks..

I am not an expert but the area north of Panama looks like a storm in a making, watch out we may have Alex soon.

Quoting Baltimorebirds:
What happen.It's been cloudy in batimore all day.

is Baltimore nice? How far from DC is it? I was going to go to DC for vacation and I wanted to see Baltimore

Quoting Levi32:


The wave is strongest in the low-levels, from the surface to 850mb, and then becomes progressively weaker as you go above that. It is weaker at 700mb and weaker still at 500mb. This happens a lot after a tropical wave has passed the point on its journey west where the AEJ ceases to exist (it only extends a little way out into the eastern Atlantic).

Oh, thanks for the explanation.

Out to play tennis on this very nice summer day here (51 degrees, yes that is shorts weather for me).

Later all.

Quoting pottery:

WOW! I have had a touch over 5" in that timespan. But 3+" fell today!

Why Uncle has some business clients in the Antilles. Apparently have had their gardens ruined every few years from the amount of rain that can fall there.

ECMWF NAO

Quoting Levi32:
Out to play tennis on this very nice summer day here (51 degrees, yes that is shorts weather for me).

Later all.

51 is shorts weather? O_o?
I would be a ball off jackets with that temp, LOL!

Quoting Levi32:
Out to play tennis on this very nice summer day here (51 degrees, yes that is shorts weather for me).

Later all.

Last time I was in sub 60 degree weather was early April.

If can stay healthy...

Quoting DDR:
How was your trip to our sister isle?

Bumpy. Rain. Lightening and squalls there.
Got everything done though.
The Captain of the aircraft came all the way down the coast to Maracas Bay before crossing. Big thunder-heads just east of that. Saw an American Airlines flight leave Piarco and turn south a bit, to go around them.
That was at about 3:30. Did the rain from that get to you?

Quoting Baltimorebirds:
It's about 40-45 miles the most from d.c.Baltimore is a very historic city.You should go visit the harbor,and the aqurium.Nice place to be,especially for the kids.

It seems so nice on tv

Baltimorebirds you should drop by my blog some great info there and post a hello for me will ya

12z ECMWF develops the African wave into Alex.

Develops it at 96 hours...

Heres 168: