384 
 WTNT44 KNHC 030257
 TCDAT4
 
 HURRICANE MATTHEW DISCUSSION NUMBER  20
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL142016
 1100 PM EDT SUN OCT 02 2016
 
 Although an Air Force Reserve reconnaissance aircraft investigating
 Matthew this evening has yet to report flight-level or surface
 winds anywhere close to the 130-kt winds measured in the previous
 flight, recent aircraft data have indicated that the surface
 pressure and 700-mb height have both decreased since the previous
 flight. The eye has cleared out in infrared satellite imagery and
 cloud tops have cooled around the 8-12 nmi diameter eye. Given the
 lower central pressure of 943 mb, which corresponds to about 120 kt
 on the Dvorak pressure-wind relationship, the small eye, and recent
 NHC objective T-numbers of T6.3/123 kt to T6.5/127 kt, the initial
 intensity will remain at 125 kt for this advisory.
 
 Matthew has continued to meander and wobble over the past several
 hours, but the best estimate of the forward motion based on recent
 recon fixes is 360/04 kt. Although some erratic motion could still
 occur due to Matthew interacting with a large convective complex and
 mid-/upper-level vortex located about 150 nmi east of Matthew, the
 cyclone is expected to move in a general northward direction for the
 next 48 hours or so. After clearing the northeastern coast of Cuba,
 Matthew is expected to turn toward the north-northwest within
 southeasterly flow between the western periphery of a strong ridge
 located over the southwestern Atlantic and a weak mid- to
 upper-level trough currently located over the eastern Gulf of
 Mexico. The 12Z UKMET and 18Z GFS and GFS-ensemble mean models now
 show a weaker trough over the Gulf of Mexico on days 3-5 as a larger
 storm system currently located over the northwestern U.S. is
 forecast to not be as strong or as far south as previously expected.
 This has resulted in more downstream ridging in those models over
 the southeastern United States, and the model tracks of Matthew have
 responded by shifting westward. The new NHC track forecast has been
 shifted slightly to the west or left of the previous advisory track,
 mainly to account for the more westward initial position. However,
 the forecast track remains to the east of the UKMET, GFS, and
 GFS-ensemble mean models, and lies near the TVCX consensus model.
 
 Matthew is forecast to remain in a low vertical wind shear
 environment for the next 36-48 hours, with the shear reaching near
 zero values by 24 hours. This condition, along with the very
 favorable upper-level outflow pattern noted in water vapor imagery,
 should allow for the cyclone to at least maintain its current
 intensity, barring the eye making any direct interactions with
 Jamaica or Haiti. By 48 hours, however, land interaction with
 eastern Cuba should induce more significant weakening. The official
 intensity forecast remains near or above the latest model consensus.
 
 Although the official forecast continues to show a track east of
 Florida, it is still too soon to rule out possible hurricane impacts
 there.  It is also too soon to know whether, or how, Matthew might
 affect the remainder of the United States east coast.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  03/0300Z 14.7N  75.0W  125 KT 145 MPH
  12H  03/1200Z 15.7N  75.1W  125 KT 145 MPH
  24H  04/0000Z 17.1N  75.0W  125 KT 145 MPH
  36H  04/1200Z 18.8N  74.8W  120 KT 140 MPH
  48H  05/0000Z 20.6N  74.9W  105 KT 120 MPH...INLAND
  72H  06/0000Z 24.0N  75.6W  105 KT 120 MPH...OVER WATER
  96H  07/0000Z 27.1N  76.6W   95 KT 110 MPH
 120H  08/0000Z 30.1N  76.7W   90 KT 105 MPH
 
 $$
 Forecaster Stewart