TROPICAL STORM KAY DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL EP122016
300 AM MDT FRI AUG 19 2016
The center continues to be on the edge or very near a large area of
developing convection. Dvorak T-number estimates remain below
tropical storm strength, but a recent ASCAT-B pass around 0500 UTC
showed a few wind vectors of 35 kt in the southeastern quadrant. On
this basis, the depression has been upgraded to tropical storm
status. Kay continues to be affected by northeasterly shear, but
conditions are still favorable for slight strengthening during the
next 24 hours before the cyclone encounters a more stable
environment. After that time, gradual weakening should begin.
The best estimate of the initial motion is 315/06. Kay is embedded
within light steering currents around a weak ridge over Mexico, and
this pattern is forecast to change little. Most of the track models
keep Kay moving northwestward with a gradual bend to the west as the
cyclones weakens. The exception is the GFS which brings a very weak
system close to Baja California. This GFS solution does not appear
to be realistic at this time. The NHC forecast follows the bulk of
the guidance, shifting a little bit to the left from the previous
NHC forecast and following the multimodel consensus TVCN.
Showers and thunderstorms gradually continue to become better
organized in association with a low pressure system located about
350 miles west-southwest of Manzanillo, Mexico. Upper-level winds
are expected to become more conducive for a tropical depression to
form tonight or tomorrow while this system moves generally
northwestward.
1. * Formation chance through 48 hours...high...70 percent
* Formation chance through 5 days...high...70 percent
1. An area of low pressure located about 330 miles southwest of
Manzanillo, Mexico, is producing disorganized showers and
thunderstorms. Upper-level winds are forecast to be marginally
conducive for gradual development of this system during the next
few days while it moves northwestward. Environmental conditions
are expected to become less conducive for development by late in
the weekend.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...medium...60 percent