000
WTPZ42 KNHC 200245
TCDEP2

TROPICAL STORM KAY DISCUSSION NUMBER   6
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122016
900 PM MDT FRI AUG 19 2016

Kay has been able to maintain a large CDO pattern, and the low-level
circulation has moved farther into the northeastern portion of the
convective cloud shield. The upper-level outflow has also been
increasing, except in the northeastern quadrant where it is
restricted by modest northeasterly vertical wind shear. Satellite
classifications are a consensus T3.0 from TAFB and SAB, and ADT
values have been steadily increasing and are now T3.6/57 kt. Based
on these data, the initial intensity has been increased to 45 kt.

Microwave satellite data indicate that Kay is moving northwestward
or 305/6 kt. There is no change to the previous forecast reasoning.
A weak subtropical ridge currently located over northern Mexico and
the Baja California peninsula is forecast to build westward to the
north of Kay during the next 5 days, which will gradually turn the
storm toward the west-northwest during the next 3 days. After that,
a westward motion is expected on days 4 and 5 when Kay will be a
shallow remnant low steered by weak low-level easterly tradewind
flow. The new forecast track is essentially just an update of the
previous advisory track, and lies close to but a little slower than
the consensus model TVCN.

The official intensity forecast shows no change in strength for the
next 36 hours due to expected intrusions of dry mid-level air that
will cause fluctuations in the convective structure that can not be
predicted temporally. With the 850-200-mb vertical wind shear
expected to remain low at around 5 kt for the next 48 hours, it is
not out of the question that some slight strengthening could occur.
However, long-term or rapid intensification is not expected due to
the Kay moving into a drier, more stable air mass and over
progressively cooler SSTs. The official intensity forecast is the
same as the previous advisory, and remains a little above the IVCN
consensus model and near an average of the SHIPS/LGEM intensity
models.

FORECAST POSITIONS AND MAX WINDS

INIT  20/0300Z 19.2N 112.4W   45 KT  50 MPH
 12H  20/1200Z 19.7N 113.0W   45 KT  50 MPH
 24H  21/0000Z 20.3N 113.7W   45 KT  50 MPH
 36H  21/1200Z 20.9N 114.6W   45 KT  50 MPH
 48H  22/0000Z 21.4N 115.5W   40 KT  45 MPH
 72H  23/0000Z 22.4N 117.5W   35 KT  40 MPH
 96H  24/0000Z 23.1N 119.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  25/0000Z 23.5N 122.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Stewart