ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM FRED DISCUSSION NUMBER  26
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062015
500 AM AST SAT SEP 05 2015

Fred continues to produce bursts of convection, although the bursts
are smaller and farther from the center than they were 24 hours
ago. This suggests that the ongoing 35-40 kt of westerly vertical
shear is causing a gradual weakening.  The initial intensity remains
35 kt based on a subjective satellite intensity estimate from TAFB,
as well as objective AMSU and satellite consensus estimates from
CIMSS and CIRA.  The central pressure has been lowered a little
based on additional observations from drifting buoy 13519, which
reported a minimum pressure of 1008.4 mb as the center of Fred
passed to the north.

The initial motion is 290/10.  Fred is approaching a large break in
the subtropical ridge caused by a mid- to upper-level trough and
associated surface low centered several hundred miles east of
Bermuda.  The track guidance is in good agreement that this
baroclinic system will move eastward for the next several days, with
Fred recurving to the northeast between it and the subtropical
ridge.  After recurvature, there is some spread in the forecast
forward speed, with the new track compromising between the faster
ECMWF/GFS models and the slower UKMET/Canadian models.  The new
track is nudged slightly to the north of the previous track from
36-96 hours, and then is nudged a little to the east of the previous
track at 120 hours.

The intensity forecast is low in confidence due to several possible
scenarios.  First, although it is not explicitly forecast, Fred
could become a remnant low at any time during the next 24 to 36
hours due to continued shear and dry air entrainment, followed by
regeneration to a tropical cyclone when the shear subsequently
decreases.  Second, the dynamical models have two scenarios for Fred
as it interacts with the above-mentioned trough and surface low
after recurvature. One possibility, supported by the GFS and the
ECMWF, is that a relatively weak Fred gets absorbed into the
baroclinic low and dissipates earlier than currently forecast.
Another possibility, supported by the UKMET and Canadian models, is
that Fred stays farther away from the baroclinic low and intensifies
more than is currently forecast. Given the uncertainty, the new
intensity forecast is similar to the previous forecast in calling
for slight weakening early in the forecast period followed by slight
intensification after 36 hours.

FORECAST POSITIONS AND MAX WINDS

INIT  05/0900Z 23.2N  41.0W   35 KT  40 MPH
 12H  05/1800Z 23.7N  42.1W   30 KT  35 MPH
 24H  06/0600Z 24.7N  42.7W   30 KT  35 MPH
 36H  06/1800Z 26.3N  42.5W   30 KT  35 MPH
 48H  07/0600Z 28.2N  41.1W   35 KT  40 MPH
 72H  08/0600Z 31.5N  37.5W   35 KT  40 MPH
 96H  09/0600Z 35.0N  33.0W   35 KT  40 MPH
120H  10/0600Z 36.5N  30.0W   35 KT  40 MPH

$$
Forecaster Beven

Mas que metedura de pata es un caso raro que no se comprende bien, porque en esas condiciones tan adversas que siga manteniéndose como TS es un misterio. Rarezas de ese tipo no son las primeras

00
WTNT41 KNHC 051444
TCDAT1

TROPICAL STORM FRED DISCUSSION NUMBER  27
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062015
1100 AM AST SAT SEP 05 2015

Fred has been decapitated again by strong westerly wind shear.
However, the low-level circulation continues to be vigorous. The
initial intensity remains at 35 kt, based on satellite estimates and
continuity.  I will not speculate any more about the convection
redeveloping or not. The NHC forecast calls for little change in
intensity during the next 36 hours. If resilient Fred survives the
next day or so, there is a chance of slight re-intensification as
indicated by the SHIPS/GFS and SHIPS/ECMWF intensity guidance.

Fred is about to reach a break in the subtropical ridge where the
steering currents are weaker, and is now moving toward the west-
northwest at about 7 kt.   A turn to the northwest and north should
begin later today, and by Sunday night, Fred should recurve as it
becomes embedded within the mid-latitude westerly flow. The NHC
forecast follows the trend of all the models, but is closer to the
GFS and the ECMWF solutions.


FORECAST POSITIONS AND MAX WINDS

INIT  05/1500Z 23.4N  41.8W   35 KT  40 MPH
 12H  06/0000Z 23.9N  42.7W   30 KT  35 MPH
 24H  06/1200Z 25.5N  43.0W   30 KT  35 MPH
 36H  07/0000Z 27.5N  41.5W   30 KT  35 MPH
 48H  07/1200Z 29.5N  40.0W   35 KT  40 MPH
 72H  08/1200Z 31.5N  37.0W   40 KT  45 MPH
 96H  09/1200Z 33.0N  34.0W   40 KT  45 MPH
120H  10/1200Z 33.0N  32.0W   40 KT  45 MPH

$$
Forecaster Avila

000
WTNT41 KNHC 060837
TCDAT1

TROPICAL DEPRESSION FRED DISCUSSION NUMBER  30
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062015
500 AM AST SUN SEP 06 2015

Thunderstorm activity has continued to pulse near the center of
Fred overnight, however, strong northwesterly shear is causing
the cloud tops to be quickly shunted southeastward.  The initial
intensity is maintained at 30 kt, which is in agreement with a
Dvorak T-number of 2.0 from TAFB.  Little overall change in strength
is expected today.  In 24 to 36 hours the shear is expected to
diminish, which could allow a brief opportunity for Fred to
restrengthen.  After that time, the cyclone is expected to enter an
area of stronger westerly upper-level winds and cooler SSTs, which
should halt further intensification. Late in the period, strong
shear and marginal SSTs should cause weakening.  An alternate
scenario shown by the ECMWF is for the shear to cause Fred to
weaken and become a trough of low pressure within the next 12
to 24 hours.

Fred has finally made its much anticipated northward turn.  A turn
toward the northeast should occur later today as the cyclone is
steered around the western periphery of a low-level ridge to its
northeast.  A turn toward the east and then southeast are forecast
late in the period as a high pressure ridge builds to the north of
the cyclone.  The new NHC track is similar to the previous advisory
and is in best agreement with the 0000 UTC GFS model.

FORECAST POSITIONS AND MAX WINDS

INIT  06/0900Z 24.9N  43.2W   30 KT  35 MPH
 12H  06/1800Z 26.0N  43.0W   25 KT  30 MPH
 24H  07/0600Z 27.5N  41.9W   25 KT  30 MPH
 36H  07/1800Z 29.2N  40.1W   30 KT  35 MPH
 48H  08/0600Z 30.5N  38.5W   35 KT  40 MPH
 72H  09/0600Z 32.2N  36.0W   35 KT  40 MPH
 96H  10/0600Z 32.5N  33.5W   35 KT  40 MPH
120H  11/0600Z 31.5N  32.0W   30 KT  35 MPH

$$
Forecaster Brown