Development with Tropical Wave in MDR?

[cycloneye]

Pic that shows shear mainly north of 15N,wave 1 and wave 2.

[gatorcane]

Here is a snippet from HPC's Caribbean forecast discussion issued 217pm EDT Thu. Jul 16 2009.

The TUTT they mention is what is creating the high shear out ahead of the wave and which should prevent development of this wave. This TUTT feature is very common for July and is part of the reason why the Caribbean is *typically* shut down this month.

But one thing to pay attention to is the possibility this wave flares up as it approaches the shear which may provide some very intense rainfall for the Eastern Caribbean islands as discussed here. Cycloneye has already discusses this rain possiblity.

AT 250 HPA...A TUTT EXTENDS ACROSS THE CENTRAL ATLANTIC TO THE
NORTHEAST CARIBBEAN ISLANDS...THEN WEST ACROSS HISPANIOLA TO
ANOTHER TUTT OVER THE NORTHWEST CARIBBEAN. THE UPPER TROUGH WILL
REMAIN ALONG 20N DURING THE NEXT THREE DAYS...SEPARATING A RIDGE
OVER THE WESTERN ATLANTIC FROM ANOTHER OVER THE TROPICAL ATLANTIC.
AS THE AFOREMENTIONED MID LEVEL RIDGE WEAKENS LATER IN THE
CYCLE...THE TUTT ALOFT WILL PROVIDE THE VENTILATION TO DEEP
CONVECTION ACROSS THE EASTERN CARIBBEAN ISLANDS.

http://www.hpc.ncep.noaa.gov/discussions/fxca20.html

[StormTracker]

Does anybody have a handle on how long that 50-60kt shear has been in place & do we know when it may start decreasing? I doubt we'll see wave #2 flat-line below the shear and develop!

[Macrocane]

:?: Does anybody have a handle on how long that 50-60kt shear has been in place & do we know when it may start decreasing? I doubt we'll see wave #2 flat-line below the shear and develop!

It may start to decrease in 96-120 h most of all in the Caribbean and north of the ITCZ, you could take a look at these loops:

http://www.meteo.psu.edu/~gadomski/COMPSHEARATL_0z/comploop.html

[StormTracker]

:?: Does anybody have a handle on how long that 50-60kt shear has been in place & do we know when it may start decreasing? I doubt we'll see wave #2 flat-line below the shear and develop!

It may start to decrease in 96-120 h most of all in the Caribbean and north of the ITCZ, you could take a look at these loops:

http://www.meteo.psu.edu/~gadomski/COMPSHEARATL_0z/comploop.html

I can't get that link to work MC!

[StormTracker]

:?: Does anybody have a handle on how long that 50-60kt shear has been in place & do we know when it may start decreasing? I doubt we'll see wave #2 flat-line below the shear and develop!

It may start to decrease in 96-120 h most of all in the Caribbean and north of the ITCZ, you could take a look at these loops:

http://www.meteo.psu.edu/~gadomski/COMPSHEARATL_0z/comploop.html

I can't get that link to work MC!

Working now...thanks!

[AtlanticWind]

Jeff Masters

There's finally a African tropical wave worth mentioning, in what has been a very inactive June/July period for African waves with a potential to develop. A tropical wave near 12N 36W, about 1000 miles west of the coast of Africa, is triggering some modest heavy thunderstorm activity over the open ocean as the storm moves west at 10 - 15 mph. Wind shear is a modest 15 knots over the disturbance, which is low enough to allow some slow development over the next few days. As long as the disturbance stays south of Puerto Rico's latitude (18°N), wind shear should remain low enough to allow development. However, there is a substantial amount of African dust and dry air surrounding the system on its west and north sides. This dry air will retard development, and may be able to completely disrupt the disturbance at some point over the next 3 - 4 days. None of the computer models develop the disturbance. The National Hurricane Center is giving this system a low (less than 30% chance) of developing into a tropical depression in the next 48 hours.

[HURAKAN]

Convection needs to be more consistent.

[cycloneye]

Visible loop.

[floridasun78]

it look like storm are increasing with wave that nhc talking about in last few frame

[cycloneye]

Well peeps guess what,we have INVEST!!.Thread is locked and all the discussions about this disturbance are now at Active Storms forum.

Link to invest 97L thread.

viewtopic.php?f=59&t=105863&hilit=&p=1893100#p1893100