Skip Navigation Links
NOAA NOAA United States Department of Commerce

Hurricane FERNANDA


ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM

Hurricane Fernanda Discussion Number  32
NWS National Hurricane Center Miami FL       EP062017
200 PM PDT Wed Jul 19 2017

Fernanda continues to slowly weaken, with the convection gradually
decreasing in coverage and intensity due to cool sea surface
temperatures and increasing shear.  The initial intensity is
reduced to 70 kt based on a blend of the various satellite
intensity estimates, and this value is on good agreement with the
CIMSS satellite consensus.

The initial motion is now 300/7.  Fernanda is expected to continue
this motion through 72 h as it is steered by a strong low- to
mid-level ridge to the north.  This ridge is forecast to persist
after 72 h.  However, the guidance continues to show divergence
during that time, with the models that forecast Fernanda to weaken
more quickly showing a more westward motion.  One change in the
guidance since the last advisory is that the GFS and the HWRF show a
more westward motion after 72 h than previously, and this has helped
shift the consensus models southward to near the old forecast track.
Based on this, the new forecast track is changed little since the
previous advisory, and lies near the current runs of the consensus
models.

Fernanda is expected to steadily weaken through the forecast period
due to various combinations of cool sea surface temperatures,
southwesterly to southerly shear, and dry air entrainment.  One
change from the previous advisory is to keep the system as a
tropical cyclone at 72 h based on the GFS and ECMWF forecasting
associated organized convection at that time.  Otherwise, the new
intensity is similar to the previous forecast and in good agreement
with the intensity consensus.

The initial and forecast wind radii have been revised based on a
just-received scatterometer overpass.


FORECAST POSITIONS AND MAX WINDS

INIT  19/2100Z 17.7N 136.3W   70 KT  80 MPH
 12H  20/0600Z 18.1N 137.3W   60 KT  70 MPH
 24H  20/1800Z 18.7N 139.0W   50 KT  60 MPH
 36H  21/0600Z 19.2N 140.6W   40 KT  45 MPH
 48H  21/1800Z 19.7N 142.2W   35 KT  40 MPH
 72H  22/1800Z 21.0N 145.5W   30 KT  35 MPH
 96H  23/1800Z 22.0N 149.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  24/1800Z 23.0N 155.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Beven

NNNN