ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM

Tropical Storm Kristy Discussion Number  12
NWS National Hurricane Center Miami FL       EP132018
200 PM PDT Thu Aug 09 2018

Kristy's deep convection has been waxing and waning, with an overall
decrease a few hours ago followed by a recent increase near the
center.  The advisory intensity is kept at 55 kt, in agreement with
objective ADT values from UW/CIMSS and a subjective Dvorak
classification from TAFB.  Kristy is over marginally warm waters, in
low vertical shear, and with fairly well-defined upper-level
outflow.  There is a window of opportunity of about a day for
additional intensification, and the official intensity forecast
follows the intensity model consensus and the LGEM guidance.  A
weakening trend is likely to commence by Friday night, and Kristy
should degenerate into a post-tropical cyclone by late in the
weekend.

Visible imagery and some microwave data provided more accurate
center fixes than earlier today, and the initial motion is a more
confident 360/6 kt.  The main steering mechanisms for Kristy are a
weak ridge to the north and the large circulation of weakening John
to the northeast. There continues to be significant diversity in the
track models. The ECMWF and UKMET models, and their ensembles, are
substantially to the left of the other guidance with the GFS, HWRF,
and HMON much more to north and east, presumably due to interaction
with John. Since the weakening John may not be that much of an
influence, the official forecast is roughly in the middle of these
two extremes and close to the model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT  09/2100Z 16.9N 130.1W   55 KT  65 MPH
 12H  10/0600Z 17.7N 129.8W   60 KT  70 MPH
 24H  10/1800Z 19.0N 129.1W   60 KT  70 MPH
 36H  11/0600Z 20.3N 128.7W   55 KT  65 MPH
 48H  11/1800Z 21.3N 128.6W   50 KT  60 MPH
 72H  12/1800Z 23.0N 129.0W   35 KT  40 MPH...POST-TROPICAL
 96H  13/1800Z 25.0N 130.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  14/1800Z 27.0N 131.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Pasch

NNNN