Official Discussion issued by the National Hurricane Center

Joyce (AL102018) DATA RELEASED: 9/17/2018 5:00:00 PM UTC

Copy of official data

Tropical Depression Joyce Discussion Number  21
NWS National Hurricane Center Miami FL       AL102018
Issued by the NWS Weather Prediction Center College Park MD
500 PM AST Mon Sep 17 2018

Tropical Depression Joyce has proven to be resilient. Visible
satellite imagery over the eastern Atlantic today showed a
fairly prolonged burst of deep convection near and just east of the
center. In the grand scheme of things, the circulation of Joyce is
still relatively dry and free of thunderstorms, but this batch of
convection causes us to maintain a 30-knot intensity at advisory
time.

Joyce had turned decidedly to the southeast since 15Z, and
this fits in with the model guidance - all of which showed a very
strong track consensus that curves the system down away from the
westerlies, with the track eventually turning toward the southwest,
suppressed by a developing flat ridge around 35 degrees north.
Over time, this track will put Joyce in an environment characterized
by less shear, but also marginal sea surface temperatures and very
dry mid-level air. This should cause deep convection to diminish,
and gradually reduce Joyce's winds and structure to a post-tropical
low - noting that all the global models lose definition on this
system just after 72 hours.

The lastest official track is near the consensus of the tightly
clustered guidance, and represents no significant change since the
previous advisory.


FORECAST POSITIONS AND MAX WINDS

INIT  17/2100Z 33.7N  27.4W   30 KT  35 MPH
12H  18/0600Z 32.9N  26.7W   30 KT  35 MPH
24H  18/1800Z 31.8N  26.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
36H  19/0600Z 30.8N  27.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
48H  19/1800Z 30.1N  28.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
72H  20/1800Z 28.7N  31.7W   15 KT  15 MPH...POST-TROP/REMNT LOW
96H  21/1800Z...DISSIPATED

$$
Forecaster Burke/Blake