WTPZ43 KNHC 270833
TROPICAL STORM ROSLYN DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL EP182016
200 AM PDT TUE SEP 27 2016
Roslyn's center appears to be losing some definition in infrared
satellite imagery, and all of the associated deep convection is
displaced to the north and northeast due to strong southwesterly
shear. Roslyn fell within the nadir gap of the latest ASCAT
passes, but the initial intensity is set at 40 kt based on a
gradual lowering of subjective and objective Dvorak estimates.
This value is also in accordance with the most recent UW-CIMSS
SATCON estimate. Increasing shear, gradually cooling SSTs, and dry
mid-level air should induce additional weakening, and deep
convection is likely to dissipate within the next day or two.
The new NHC intensity forecast shows Roslyn becoming a remnant low
in 36 hours, and it is expected to open up into a trough by day 4.
The initial motion is now northeastward, or 050/6 kt. Roslyn is
expected to turn northward toward a deep-layer low located over the
Baja California peninsula during the next 36 hours. It should then
turn northwestward and west-northwestward on days 2 and 3 after it
has become a remnant low, steered by lower-level ridging. The
official track forecast has again been nudged east of the previous
advisory toward the latest TVCN multi-model consensus.
FORECAST POSITIONS AND MAX WINDS
INIT 27/0900Z 17.8N 117.7W 40 KT 45 MPH
12H 27/1800Z 18.7N 117.1W 35 KT 40 MPH
24H 28/0600Z 20.0N 116.6W 30 KT 35 MPH
36H 28/1800Z 21.3N 116.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 29/0600Z 22.3N 117.3W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 30/0600Z 23.5N 119.5W 15 KT 15 MPH...POST-TROP/REMNT LOW