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Hurricane DANNY


500 PM AST SAT AUG 22 2015

Satellite imagery and reports from Air Force Reserve and NOAA
Hurricane Hunter aircraft show that Danny continues to weaken.  The
aircraft have reported that the central pressure has risen to at
least 991 mb, along with maximum surface wind estimates near 65 kt
from the Stepped Frequency Microwave Radiometer.  Based on these
data, the initial intensity is decreased to 65 kt.  The aircraft
data indicate that the center of Danny is tilted to the north or
northeast with height, as dropsondes released at the calm
flight-level center have consistently reported 50-60 kt easterly
surface winds.  In addition, satellite imagery suggests that the
center is now at the southwestern edge of the convection.  These
observations are likely due to ongoing southwesterly vertical wind

The initial motion is now 285/12, a little faster than before.
There is again little change in the forecast philosophy, with Danny
expected to turn westward tonight as the subtropical ridge to the
north of the cyclone builds westward and strengthens.  This general
motion is expected to persist for the next several days taking Danny
across the Leeward Islands in about two days, and near Puerto Rico
and Hispaniola in 3 to 4 days.  This part of the forecast track is
near the center of the guidance envelope and is similar to, but a
little faster than, the previous track.  The dynamical models are
forecasting a mid- to upper-level trough to move into Florida and
the southeastern United States by 120 hours, and the track guidance
responds to this by showing a northwestward turn.  The new forecast
track also shows a more northward motion at 120 hours, but it lies
to the south and west of the center of the envelope.

Danny is expected to move through a dry and stable air mass and
encounter moderate to strong southwesterly vertical wind shear for
at least the next three days.  This should cause continued
weakening, and the cyclone is forecast to be a tropical storm as it
moves over or near the northeastern Caribbean Islands.  The
intensity forecast becomes lower confidence at days 4 and 5.  The
dynamical models forecast an upper-level low to form near central
Cuba.  However, they do not agree on how this will change the shear
over Danny.  The GFS continues forecasting significant shear, while
the ECMWF forecasts more favorable upper-level winds.  It should be
noted that even with its more favorable shear forecast, the ECMWF
forecasts Danny to weaken to a tropical wave.  Based on this and
the expectation that dry air will continue to impact the cyclone,
the intensity forecast calls for continued weakening at days 4-5.

There are no changes to the watches at this time.  However,
additional watches or warnings may be necessary for portions of the
Leeward Islands, the Virgin Islands, and Puerto Rico tonight or


INIT  22/2100Z 15.8N  53.3W   65 KT  75 MPH
 12H  23/0600Z 16.1N  55.2W   60 KT  70 MPH
 24H  23/1800Z 16.6N  57.9W   55 KT  65 MPH
 36H  24/0600Z 17.1N  60.4W   50 KT  60 MPH
 48H  24/1800Z 17.8N  62.9W   45 KT  50 MPH
 72H  25/1800Z 19.5N  68.0W   40 KT  45 MPH
 96H  26/1800Z 21.0N  72.5W   35 KT  40 MPH
120H  27/1800Z 23.0N  76.0W   30 KT  35 MPH

Forecaster Beven