Tropical Storm Wilma Advisory Number 11
Statement as of 5:00 am EDT on October 18, 2005
...Wilma almost a hurricane...expected to be one soon...
a Tropical Storm Warning remains in effect for Honduras from the
Honduras/Nicaragua border westward to Cabo camaron.
A Tropical Storm Warning and a Hurricane Watch remain in effect for
the Cayman Islands.
Wilma is expected to become an intense hurricane in the northwestern
Caribbean Sea. Therefore...all interests in western Cuba...the
Yucatan Peninsula...South Florida and the Florida Keys should
monitor the progress of this potentially dangerous hurricane during
the next several days.
For storm information specific to your area...including possible
inland watches and warnings...please monitor products issued
by your local weather office.
At 5 am EDT...0900z...the center of Tropical Storm Wilma was located
near latitude 15.7 north...longitude 80.0 west or about 260 miles
...420 km...south-southeast of Grand Cayman and about 220 miles...
350 km...east-northeast of Cabo Gracias a Dios on the Nicaragua
/Honduras border.
Wilma has been nearly stationary and little motion is expected
during the next several hours. Thereafter...a general motion to the
west is expected followed by a gradual turn toward the
west-northwest. Steering currents remain weak and erratic motion is
possible.
Maximum sustained winds have increased to near 70 mph...110
km/hr...with higher gusts. Wilma is expected to become a hurricane
today.
Tropical storm force winds extend outward up to 70 miles ...110 km
from the center.
Latest minimum central pressure measured by an Air Force
reconnaissance plane a couple of hours ago was 982 mb...29.00
inches.
Wilma is expected to produce rainfall accumulations of 4 to 6 inches
over the Cayman Islands...Jamaica...Haiti...and southeastern
Cuba...with isolated amounts of 8 to 12 inches possible. Rainfall
accumulations of 2 to 3 inches...with isolated amounts of 6 to 10
inches...are possible over Honduras.
Repeating the 5 am EDT position...15.7 N... 80.0 W. Movement
...Stationary. Maximum sustained winds... 70 mph. Minimum central
pressure...982 mb.
An intermediate advisory will be issued by the National Hurricane
Center at 8 am EDT followed by the next complete advisory at 11 am
EDT.
Forecaster Avila
Tropical Storm Wilma Discussion Number 11
Statement as of 5:00 am EDT on October 18, 2005
there are several indicators suggesting that Wilma is strengthening.
The pressure has fallen to 982 mb. The cloud pattern consists of
very deep convection near the center with banding features...and
the outflow has continued to become more symmetrical. T-numbers
from TAFB and SAB are 4.0 on the Dvorak scale...suggesting that
Wilma is a hurricane. In addition...two microwave passages from
different satellites show an eye feature. However...wind
observations from the Air Force plane do not support winds higher
than 60 knots at this time. Given the conditions of light shear and
very warm ocean...strenghtening is indicated. The official
intensity forecast is between the GFDL and the SHIPS models. Wilma
is expected to become an intense hurricane in the northwestern
caribean sea...typical of those hurricanes which commonly occurred
in October during the 30's 40's and 50's. This is nothing new.
Wilma has barely moved for the past several hours. Despite models
showing a weakening of the anticylone over the Gulf of Mexico...
this feature is still there and strong...blocking the motion of
Wilma. It is still fresh in my memory that...in 1998 with a similar
steering pattern...all models moved hurricane Mitch northward and
the hurricane indeed moved southward. However...dynamical models
have improved a lot since then and the confidence is higher. The
anticyclone in the Gulf is forecast to weaken as a large trough
sweeps eastward across the United States...and the Atlantic
subtropical ridge is also forecast to build. This should result in
a slow west to northwest motion of Wilma during the next 2 to 3
days...toward the extreme northwestern Caribbean Sea. Thereafter...
Wilma will be approaching the westerlies and recurvature with an
increase in forward speed is forecast. This is consistent with the
guidance envelope which shows a hurricane moving either over the
Yucatan Channel or western Cuba and then over the southern half of
the Florida penisula between days 4 and 5. Remember...there is a
large variability and large errors associated with the 4 and 5 day
forecasts. So at this time stay tune and monitor closely the
progress of this hurricane.
Forecaster Avila
forecast positions and Max winds
initial 18/0900z 15.7n 80.0w 60 kt
12hr VT 18/1800z 15.8n 80.4w 70 kt
24hr VT 19/0600z 16.6n 81.4w 80 kt
36hr VT 19/1800z 17.3n 82.4w 90 kt
48hr VT 20/0600z 18.6n 84.0w 100 kt
72hr VT 21/0600z 21.1n 85.0w 100 kt
96hr VT 22/0600z 23.0n 84.5w 100 kt
120hr VT 23/0600z 26.5n 80.0w 80 kt...inland