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Wilma has developed the dreaded pinhole eye. Reports from the Air
Force Reserve hurricane hunter investigating Wilma between 19z and
23z indicated a 7-8 N mi wide eye...with the central pressure
dropping from 970 mb to 954 mb in 3 hr 14 min. The maximum
flight-level winds measured by the aircraft at 850 mb were 101 kt.
Since that time...satellite imagery shows increased organization...
with a ring of cold tops of -80c to -87c surrounding the eye.
Satellite intensity estimates are 102 kt from TAFB and SAB...and 90
kt from AFWA. Based on this and extrapolation of the last aircraft
data...the initial intensity is increased to 95 kt. This may be
conservative.
The initial motion is the 12 hr motion of 285/7...although for the
past several hours the eye has been moving almost due west and
perhaps a little slower. Wilma is south of a mid/upper-level ridge
extending from northern Mexico eastward to southern Florida...and
southeast of a low-level ridge that covers the Gulf of Mexico.
Large-scale models agree that the ridges should weaken during the
next 36-48 hr as an upper-level low centered over northwestern
Arizona moves northeastward and then eastward. The ridges should
collapse completely as a deep layer trough develops over the
eastern United States after 72 hr. This combination should cause
Wilma to move generally northwestward for 48 hr or so...then turn
northward...then recurve into the westerlies after 72 hr. All
model guidance generally agrees on this scenario...although there
is some spread on the exactly where Wilma will recurve between the
left-most GFDN and right-most UKMET. The new forecast track is
adjusted somewhat to the left for the first 48 hr based on the
current position and motion...with the remainder of the forecast
track similar to the previous advisory in agreement with the model
consensus. It should be noted that the models do not completely
agree on how the eastern U. S. Trough will evolve...and these
differences could make a significant difference in what parts of
Florida Wilma will ultimately affect.

The intensity forecast has become more complicated. The current
rapid intensification and favorable environment should bring Wilma
to category four status in the next 24 hr...and it would not be a
surprise to see it reach category five before it bottoms out.
However...SSM/I data shows that the convection with the eyewall
covers a very small area...with a distinct dry moat already present
outside the eyewall. Outside of that is a broken convective band
that aircraft data shows is associated with an outer wind maximum.
Thus...it appears likely that Wilma will go through a concentric
eyewall cycle during the next 24-48 hr...and since the inner eye is
so small there could be notable weakening until the outer eyewall
contracts. Since these cycles are hard to time...the intensity
forecast will hold at 125 kt from 24-48 hr. When Wilma moves into
the Gulf of Mexico...it should encounter slightly cooler sea
surface temperatures and gradually increasing vertical shear. This
should cause a slow weakening...although it is probable that Wilma
will still be a major hurricane when it reaches the Florida
Peninsula.
The NOAA g4 jet flew its first synoptic surveillance mission on
Wilma this evening...and it will be interesting to see the impact
on the 00z model runs.
Forecaster Beven

forecast positions and Max winds

initial 19/0300z 16.8n 82.1w 95 kt
12hr VT 19/1200z 17.2n 83.1w 110 kt
24hr VT 20/0000z 18.1n 84.2w 125 kt
36hr VT 20/1200z 19.2n 85.0w 125 kt
48hr VT 21/0000z 20.4n 85.5w 125 kt
72hr VT 22/0000z 23.0n 85.5w 115 kt
96hr VT 23/0000z 26.0n 81.0w 90 kt...inland
120hr VT 24/0000z 33.0n 72.0w 75 kt

$$