[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT41 KNHC 162041
TCDAT1

TROPICAL STORM JULIA DISCUSSION NUMBER  12
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112016
500 PM EDT FRI SEP 16 2016

Satellite data and reports from an Air Force Reserve Hurricane
Hunter aircraft indicate that Julia has lost organization since
this time yesterday.  The winds have decreased in most parts of the
circulation, and the center is now well exposed to the west of the
main area of convection.  The aircraft reported a central pressure
near 1008 mb and SFMR surface wind estimates of 35 kt within 30 n
mi of the center over the northern semicircle.  These data are the
basis for keeping the initial intensity 35 kt.

The intensity forecast remains low confidence.  Currently, Julia is
in an environment of 25-35 kt of westerly vertical shear, and this
hostile environment should continue for the next 48 hours.  After
that time, the guidance remains in good agreement that the shear
should decrease.  However, it is in poor agreement as to what that
means for the cyclone.  The Canadian and UKMET continue to forecast
a stronger system, while the GFS, ECMWF, and HWRF forecast Julia to
dissipate or remain weak.  Given the current trends, there is no
change to the dissipation scenario used in the intensity forecast.
However, this forecast again is on the low edge of the intensity
guidance, and there remains a chance that Julia will survive and
re-intensify.

Julia appears to finally have stopped its eastward motion, and the
initial motion is now a somewhat uncertain 190/3.  In the next day
or so, the cyclone should be steered toward the southwest and west
by the low-level ridge to the north.  After 36 hours, a baroclinic
trough moving into the northeastern United States should weaken the
ridge and allow Julia, or its remnants, to turn northward and
eventually northeastward.  There remains a significant spread
between the much faster Canadian and ECMWF models and the slower GFS
and UKMET models.  The new forecast track favors a lower solution
and keeps Julia moving at less than 5 kt before dissipation.


FORECAST POSITIONS AND MAX WINDS

INIT  16/2100Z 30.8N  75.7W   35 KT  40 MPH
 12H  17/0600Z 30.7N  75.8W   30 KT  35 MPH
 24H  17/1800Z 30.8N  76.1W   30 KT  35 MPH
 36H  18/0600Z 31.1N  76.6W   30 KT  35 MPH
 48H  18/1800Z 31.5N  77.0W   30 KT  35 MPH
 72H  19/1800Z 33.0N  76.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  20/1800Z 33.5N  75.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  21/1800Z...DISSIPATED

$$
Forecaster Beven
This weather bulletin was brought to you by:
www.nashvilleweather.net