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 WTPZ42 KNHC 150236
 Tropical Depression Twenty-Two-E Discussion Number   3
 NWS National Hurricane Center Miami FL       EP222018
 1000 PM CDT Sun Oct 14 2018
 For the first time in the depression's (and its predecessor low's)
 existence, deep convection has persisted for more than a few hours.
 The convective canopy has been slowly expanding, although it is
 still a little restricted on the eastern side due some easterly
 shear.  Based on microwave data, the structure of the cyclone has
 been slow to improve in organization, and consensus T2.0s from TAFB
 and SAB support maintaining a 30-kt initial intensity.
 The depression is located near the western edge of a mid-level
 ridge, with a deep-layer trough located not too far to the north
 across northwestern Mexico and the western United States.  Its
 position places the depression within weak steering currents, and
 the system is likely to drift west-northwestward or even meander at
 speeds of less than 5 kt for much of the forecast period.  The track
 guidance has shifted a little more to the northwest on this cycle,
 and the NHC forecast has therefore been adjusted north of the
 previous official forecast, although not as far as the TVCN
 multi-model consensus nor the HCCA aid.  Despite this adjustment,
 the cyclone is expected to remain small, which should keep
 tropical-storm-force winds offshore of the coast of Mexico.
 The forecast reasoning for the future intensity has changed
 substantially.  For the first 3 days, vertical shear is expected to
 gradually decrease, and the cyclone's small size will make it prone
 to significant strengthening during that period.  In fact, based on
 the Rapid Intensification Indices, the chance of a 30-kt increase
 in 24 hours is 3 times more than average, and the chance of a 65-kt
 increase in 72 hours is almost 9 times more than average.
 Therefore, the NHC intensity forecast is above most of the guidance
 through day 3, with the possibility of the depression becoming a
 hurricane during that time.  After day 3, the models are trending
 toward the cyclone entering a region of higher shear associated
 with the western U.S. trough, which would likely lead to a
 weakening trend.  Most of the intensity models suggest that the
 cyclone's intensity will peak around 3 days, and therefore the NHC
 intensity forecast now indicates weakening on days 4 and 5
 (although it is still well above most of the models).  This is a
 low-confidence intensity forecast, and additional adjustments are
 likely in future advisories.
 The small size of the circulation and its projected motion away from
 Mexico does not require tropical storm warnings or watches at this
 time. However, only a slight deviation to the right of the forecast
 track would bring stronger winds closer to the coast, which would
 require the issuance of a tropical storm warning. Regardless of the
 winds, heavy rainfall will be the primary threat along the coast of
 southwestern Mexico due to the system's slow motion, and flash
 flooding will be possible in mountainous areas.
 INIT  15/0300Z 17.5N 104.3W   30 KT  35 MPH
  12H  15/1200Z 17.7N 104.7W   35 KT  40 MPH
  24H  16/0000Z 17.7N 104.7W   40 KT  45 MPH
  36H  16/1200Z 17.8N 105.0W   45 KT  50 MPH
  48H  17/0000Z 17.9N 105.3W   50 KT  60 MPH
  72H  18/0000Z 18.4N 106.8W   65 KT  75 MPH
  96H  19/0000Z 19.3N 108.4W   60 KT  70 MPH
 120H  20/0000Z 19.6N 108.9W   55 KT  65 MPH
 Forecaster Berg
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