000
WTPZ42 KNHC 241433
TCDEP2

TROPICAL STORM FRANK DISCUSSION NUMBER  12
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP072016
900 AM MDT SUN JUL 24 2016

Frank remains a sheared tropical cyclone with microwave data showing
the center of circulation located near the northern edge of a large
mass of deep convection.  The advisory wind speed is kept at 55 kt,
between the Dvorak estimates that range from 50 to 65 kt.  The main
controlling factor for Frank's intensity is expected to be gradually
cooling waters since northeasterly shear is forecast to continue at
about the same magnitude for the next few days.  Slow weakening is
forecast by late Monday and beyond due to the cyclone moving over
marginal waters and eventually into a dry and stable air mass.  The
new forecast is very close to the previous interpolated official
prediction, and is a bit lower than the intensity consensus at long
range.

Microwave data indicate that Frank has turned to the west-
northwest, now moving at 6 kt.  A ridge centered over the
southwestern United States seems to be building in over northwestern
Mexico, causing a mid- to upper-level trough west of the Baja
California peninsula to move far enough away from Frank to have less
influence.  Frank should be steered west-northwestward or westward
at a relatively slow forward speed to the south of that ridge for
the next several days.  Other than some minor speed differences, the
guidance continues to be in relatively good agreement, and the
latest NHC track forecast is basically an update of the previous
one.

FORECAST POSITIONS AND MAX WINDS

INIT  24/1500Z 20.3N 112.4W   55 KT  65 MPH
 12H  25/0000Z 20.6N 113.3W   55 KT  65 MPH
 24H  25/1200Z 21.0N 114.4W   55 KT  65 MPH
 36H  26/0000Z 21.2N 115.5W   50 KT  60 MPH
 48H  26/1200Z 21.3N 116.8W   45 KT  50 MPH
 72H  27/1200Z 22.2N 119.7W   35 KT  40 MPH
 96H  28/1200Z 23.0N 122.5W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  29/1200Z 23.0N 125.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Blake