Tropical Cyclone Discussion
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000
WTPZ43 KNHC 282032
TCDEP3

TROPICAL STORM HERNAN DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082014
200 PM PDT MON JUL 28 2014

The cloud pattern of Hernan continues to degrade in appearance,
and what little deep convection remains is confined mainly to the
south of the center.  The current wind speed estimate has been
reduced to 45 kt based on a blend of intensity estimates from SAB
and TAFB along with objective Dvorak numbers from UW-CIMSS.  The
storm is now moving over waters cooler than 26 deg C, and sea
surface temperatures should continue to decrease beneath the
cyclone.  These hostile oceanic conditions, combined with moderately
strong south-southwesterly shear, are likely to bring about
continued weakening.  The official intensity forecast shows Hernan
degenerating into a remnant low in 36 hours, but the latest
intensity model guidance suggests that the system could weaken even
faster than indicated here.

Hernan continues on its west-northwestward trek, and the initial
motion is estimated to be 300/15 kt.  A mid-level ridge over the
southwestern United States and northwestern Mexico should impart a
continued west-northwestward motion for the next couple of days.
Thereafter, the dying cyclone is expected to turn westward since
the steering should become dominated by the low-level tradewind
flow.  The official track forecast is quite similar to the previous
NHC track and is very close to the latest dynamical model consensus
forecast, TVCE.

FORECAST POSITIONS AND MAX WINDS

INIT  28/2100Z 21.3N 117.3W   45 KT  50 MPH
 12H  29/0600Z 22.4N 119.3W   40 KT  45 MPH
 24H  29/1800Z 23.6N 121.5W   30 KT  35 MPH
 36H  30/0600Z 24.2N 123.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  30/1800Z 24.5N 124.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  31/1800Z 24.5N 126.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  01/1800Z...DISSIPATED

$$
Forecaster Pasch



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