000
WTNT41 KNHC 300847
TCDAT1

TROPICAL STORM FRED DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062015
500 AM AST SUN AUG 30 2015

The convective cloud pattern of the tropical cyclone has continued
to improve this early morning with the development of a small CDO
feature and a tightly curved band in the western and southern
quadrants. A 0542 UTC SSMI/S microwave satellite image further
indicated that the convective band wraps almost completely around a
primitive mid-level eye feature. The initial intensity is raised to
35 kt based on a Dvorak classification of T2.5/35 kt from TAFB, and
this intensity could be conservative based on the impressive SSMI/S
satellite signature. This makes Fred only the fourth Atlantic
tropical storm to form east of 19W longitude in NHC's database.

The initial motion remains 305/10 kt. There is no change to the
previous forecast track reasoning. Fred is expected to move
northwestward toward a weakness just northwest of the Cape Verde
Islands within a deep-layer subtropical ridge. The mid-tropospheric
trough that is responsible for the weakness is forecast by the
global and regional models to shift eastward over the next 24-36
hours, which should allow the ridge to build back in, forcing Fred
on a west-northwestward to westward track after 48-72 hours. The
latest NHC model guidance is tightly packed about the previous
forecast track, so the new track forecast is essentially just an
update of the previous advisory, and lies close to the GFEX and TVCA
consensus model solutions.

Fred is expected to remain in favorable environmental and oceanic
conditions for the next 36 hours, characterized by vertical wind
shear less than 10 kt, mid-level humidity values greater than 70
percent, and sea-surface temperatures of 27.5-28 deg C. The main
inhibiting factor is decreasing instability ahead of the cyclone
after 24 hours. However, there should still be enough available
instability to support deep convection that will allow at least
steady strengthening through 36 hours to occur, and Fred could still
reach hurricane status before or while it moves through the Cape
Verde Islands in 36 hours or so. After 48 hours, southwesterly
vertical wind shear is expected to begin affecting the cyclone while
Fred is moving over sub-27C SSTs. These less favorable conditions
should combine to induce a gradual weakening trend. The NHC
intensity forecast is similar to the previous advisory and the IVCN
intensity consensus model.

FORECAST POSITIONS AND MAX WINDS

INIT  30/0900Z 12.4N  18.9W   35 KT  40 MPH
 12H  30/1800Z 13.4N  20.3W   45 KT  50 MPH
 24H  31/0600Z 14.6N  22.1W   55 KT  65 MPH
 36H  31/1800Z 16.0N  23.9W   60 KT  70 MPH
 48H  01/0600Z 17.0N  25.8W   60 KT  70 MPH
 72H  02/0600Z 18.5N  29.9W   60 KT  70 MPH
 96H  03/0600Z 19.2N  34.0W   55 KT  65 MPH
120H  04/0600Z 19.8N  38.8W   50 KT  60 MPH

$$
Forecaster Stewart

000
WTNT41 KNHC 301450
TCDAT1

TROPICAL STORM FRED DISCUSSION NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062015
1100 AM AST SUN AUG 30 2015

Visible satellite imagery indicates that convection associated
with the tropical cyclone continues to organize.  A curved band of
convection now wraps almost completely around the center and recent
images show that a small CDO feature has developed. An earlier
WindSat microwave overpass also revealed a well-defined inner core.
Dvorak T-numbers from TAFB and UW/CIMSS are around 3.0, and based on
these the initial intensity is raised to 45 kt.

The environment ahead of Fred appears conducive for strengthening
during the next 24 to 36 hours.  During that time, there will
be sufficient mid-level moisture, the shear is expected to remain
low, and the cyclone will be traversing sea surface temperatures
of 27 to 28C.  Therefore, steady strengthening is anticipated and
the SHIPS and LGEM models bring Fred to hurricane status within
24 hours.  Strengthening is also supported by the GFS and ECMWF
models, which both show the cyclone deepening while it moves through
the Cape Verde Islands.  After 36 hours, lower sea surface
temperatures, increasing southwesterly shear, and a more stable
environment should cause weakening.

Fred is moving northwestward at about 11 kt. The tropical storm is
forecast to move northwestward toward a break in the subtropical
ridge to the north of the Cape Verde Islands.  In a couple of days,
the ridge is forecast to build westward, which should cause Fred to
turn west-northwestward.  As Fred weakens and become a more shallow
cyclone late in the period, a westward to west-northwestward
motion is expected.  The NHC track is near the consensus of the
ECMWF and GFS models through 72 hours.  Later in the period, the NHC
forecast shows a weaker system moving more westward, and this track
is along the southern edge of the guidance in best agreement with
the ECMWF.

Based on this track and intensity forecast, the Meteorological
Service of the Cape Verde Islands has issued a Hurricane Warning
for those islands.

Please note that the track/cone graphic, an automatically generated
product, does not have the capability of displaying warnings for the
Cape Verde Islands.

FORECAST POSITIONS AND MAX WINDS

INIT  30/1500Z 13.4N  19.9W   45 KT  50 MPH
 12H  31/0000Z 14.3N  21.3W   55 KT  65 MPH
 24H  31/1200Z 15.7N  23.1W   65 KT  75 MPH
 36H  01/0000Z 17.2N  25.1W   65 KT  75 MPH
 48H  01/1200Z 18.3N  27.1W   65 KT  75 MPH
 72H  02/1200Z 19.5N  31.5W   55 KT  65 MPH
 96H  03/1200Z 20.5N  35.5W   45 KT  50 MPH
120H  04/1200Z 21.0N  39.5W   40 KT  45 MPH

$$
Forecaster Brown

Eric Blake
‏@EricBlake12
#Fred has prompted a #hurricane warning for the #CapeVerde Islands-- believe it is the 1st on record there!

Vamos a ver si Fred nos envía aunque sea algo de nubosidad a las islas y poder ver algo, pero. 

Cita de: GranCanario345 en Agosto 30, 2015, 18:29:37 pm

Vamos a ver si Fred nos envía aunque sea algo de nubosidad a las islas y poder ver algo, pero. 

nubosidad alta garantizada y media tal vez...