Too much Rum for Tomas
Posted by JAC on 11/1/2010, 6:56 am
For the last 48 hrs Tomas has been suffering from the effects of the strong MCS that was firing to his east and SE Friday and Saturday.

The MCS created a localized lift in the tropopause over it and what that looks like is a shift in the anti-cyclone to Tomas' east and SE.

So, as Tomas moves away from the anti-cyclone, it moves into a region where the tropopause becomes lower in height.

Two effects from that:

1) The PV column gets compressed, and as a result from conservation of momentum, it spins at a lower rate.

2) Convection gets tilted toward the anti-cyclone which then causes a downdraft that affects inflow of moist air in the boundary-layer.

The overall effect is what looks like shear.

What needs to happen is that the anti-cyclone has to get over the LLC; or at least closer to it, for the PV column to begin to expand vertically.

A good way to do that is for very strong convection with high rain-rate to fire near the LLC.

That causes latent heating near the LLC.

Two effects of that:

1)  It will cause the tropopasue height "bubble" to move closeer to the LLC,  That will look like a shift in the anti-cyclone closer to the LLC.

2)  Lookling at the core-temp, there is a very strong boundary layer inversion.  It needs to be broken.  A higher core temp along with mixing will break that inversion.

So, cloud tops are high, around 60k-ft.

Rain-rate is beginning to increase.

Tomas is moving into higher OHC.

If the inversion gets broken, it will be like one of those massive popup torando-ally supercells and Tomas could explode.

Keep an eye on core-temp and the boundary-layer inversion (convective cap).

I wouldn't be calling Haiti out of the woods yet, not by a long shot.


















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Too much Rum for Tomas - JAC, 11/1/2010, 6:56 am
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