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Tropical Storm HERNAN


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TROPICAL STORM HERNAN DISCUSSION NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082014
200 AM PDT MON JUL 28 2014

Hernan is now on a weakening trend.  The coverage of deep convection
has decreased markedly over the past several hours, and the cloud
pattern has a more elongated appearance than it did earlier.
Microwave images also show a pronounced vertical tilt of the vortex
due to about 15 kt of westerly shear.  Dvorak and ADT intensity
estimates have decreased from all agencies, and using a blend of the
CI- and T-numbers yields an initial intensity of 60 kt. A
combination of moderate shear, a dry stable air mass, and decreasing
sea surface temperatures should cause Hernan to continue weakening
during the next few days.  The system is expected to become a
remnant low in about 2 days when it is forecast to be over waters
cooler than 23 C.

The storm has turned slightly to the left, and the latest initial
motion estimate is 300/13 kt.  This general motion should continue
for the next 24 hours while Hernan remains steered by a strong
mid-level high over the southwestern United States.  After that
time, a gradual turn to the west with a decrease in forward speed
is predicted when the shallow system becomes more influenced by the
lighter low-level flow.  The official track forecast is just a
little to the left of the previous one, and near the multi-model
consensus TVCE.

FORECAST POSITIONS AND MAX WINDS

INIT  28/0900Z 19.9N 114.5W   60 KT  70 MPH
 12H  28/1800Z 20.9N 116.4W   50 KT  60 MPH
 24H  29/0600Z 22.3N 118.8W   45 KT  50 MPH
 36H  29/1800Z 23.4N 120.6W   35 KT  40 MPH
 48H  30/0600Z 24.1N 122.2W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  31/0600Z 24.5N 124.2W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  01/0600Z 24.5N 126.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  02/0600Z...DISSIPATED

$$
Forecaster Cangialosi

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