Figure 1. Structure of the model. Potential radius, 
, is used as
the model radial coordinate. 
is the physical radius of surfaces
at the sea surface and 
is the physical radius of surfaces at the
tropopause; these are predicted quantities. The thermodynamic variables are
, 
, and 
and the mass streamfunction 
is
defined in the middle troposphere. 
is the diagnosed streamfunction
at the top of the subcloud layer.
Figure 2. Evolution with (nondimensional) time of the maximum (nondimensional) azimuthal velocity for the control run of the present model (solid) and of the original E89 model (dashed) run with the same parameters and initial and boundary conditions.
Figure 3. Evolution with time of the maximum azimuthal velocity
for three different values of the parameter 
, which influences
the rate of moistening of the lower troposphere by convection.
Figure 4. Evolution with time of the maximum azimuthal velocity
for a run identical to the control but starting with a velocity
amplitude of only 
(solid), and a similar run but starting from
a condition in which the whole atmospheric column is saturated inside
the radius 
(dashed).
Figure 5. The convective updraft volume flux (
) and clear
air vertical velocity (
) at 6.8 days, plotted as a
function of radius from the storm center, in a run identical to the
control but with the initial entropy deficit of the middle
troposphere, 
reduced to 
. For perspective, the
radius and velocity scales have been expressed in dimensional terms
using the typical scaling values shown in Table 1. A new eyewall has
just formed near 
km radius; it then moved slowly inward
while the inner eyewall dissipated.