Official Discussion issued by the National Hurricane Center

Kirk (AL122018) DATA RELEASED: 9/23/2018 5:00:00 PM UTC

Copy of official data

Tropical Storm Kirk Discussion Number   6
NWS National Hurricane Center Miami FL       AL122018
500 PM AST Sun Sep 23 2018

Deep convection has diminished near the estimated center of Kirk,
and the main thunderstorm activity is occurring over the
northwestern and western peripheries of the circulation.  This has
the appearance of an arc cloud, suggesting that some drier mid-level
air has been entrained into the tropical cyclone.  Since the system
should be moving over warmer waters and through low vertical shear
for the next day or so, some strengthening is anticipated into
early this weak.  Later in the forecast period, Kirk should be
encountering increasing shear associated with strong upper-level
westerlies over the Caribbean, and this will likely cause
weakening.  The official forecast is close to the latest Florida
State University Superensemble prediction and is the same as the
previous NHC forecast.

Based on the latest center fixes, the motion continues swiftly
toward the west, or about 280/20 kt.  A mid-level subtropical ridge
to the north of Kirk should steer the tropical cyclone westward at
a fairly fast clip for the next couple of days.  By days 3-4, the
ridge weakens a bit and Kirk should slow its forward motion
somewhat.  The official track forecast has not changed much from
the previous advisory and is close to the latest corrected
consensus model, HCCA, prediction.


INIT  23/2100Z  9.5N  32.3W   35 KT  40 MPH
12H  24/0600Z  9.9N  35.3W   40 KT  45 MPH
24H  24/1800Z 10.2N  39.5W   45 KT  50 MPH
36H  25/0600Z 10.4N  43.4W   50 KT  60 MPH
48H  25/1800Z 10.6N  47.1W   50 KT  60 MPH
72H  26/1800Z 11.6N  53.4W   45 KT  50 MPH
96H  27/1800Z 12.9N  58.1W   40 KT  45 MPH
120H  28/1800Z 14.0N  63.0W   35 KT  40 MPH

Forecaster Pasch