000 WTNT44 KNHC 282043 TCDAT4 TROPICAL STORM MATTHEW DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142016 500 PM AST WED SEP 28 2016 Surface observations and aircraft data from earlier this afternoon indicate that the circulation of Matthew has continued to become better defined. There has also been an increase in convection just northeast of the center. The initial intensity remains 50 kt based on the earlier aircraft data. The next Air Force Reserve Hurricane Hunter mission into Matthew is scheduled for this evening. Although the increase in convection suggests that the system may be trying to establish an inner core, recent microwave and radar data have not revealed a significant increase in organization or banding so far. The aircraft also did not report any pressure fall during its mission. Based on these trends, little change in intensity is predicted in the short-range, but warm waters and low shear are expected to allow for steady strengthening while Matthew moves over the eastern and central Caribbean during the next few days. The updated NHC intensity forecast is a little below the intensity consensus through 24 hours, but is close to the consensus and the statistical models after that time. Matthew is moving westward to west-northwestward at about 16 kt. The track forecast reasoning is unchanged from the previous advisory. The tropical cyclone should move generally westward during the next 2 to 3 days to the south of a strong deep-layer ridge over the western Atlantic. The new NHC track forecast has been nudged northward through 72 hours, to be closer to the new model consensus. After day 3, Matthew is expected to turn northwestward as it nears the western portion of the ridge. The overall track envelope has shifted slightly eastward at days 4 and 5, and the NHC track has been adjusted accordingly. It should be noted that are still significant differences among the models in how soon and how sharply Matthew turns northwestward and northward late in the forecast period. Users are reminded that the average NHC track errors at days 4 and 5 are on the order of 180 and 240 miles, respectively. FORECAST POSITIONS AND MAX WINDS INIT 28/2100Z 13.8N 62.0W 50 KT 60 MPH 12H 29/0600Z 14.1N 64.4W 50 KT 60 MPH 24H 29/1800Z 14.4N 67.1W 55 KT 65 MPH 36H 30/0600Z 14.4N 69.5W 65 KT 75 MPH 48H 30/1800Z 14.1N 71.3W 70 KT 80 MPH 72H 01/1800Z 14.2N 73.5W 80 KT 90 MPH 96H 02/1800Z 15.8N 75.0W 90 KT 105 MPH 120H 03/1800Z 19.0N 76.0W 90 KT 105 MPH $$ Forecaster Brown