000 WTPZ44 KNHC 231435 TCDEP4 Tropical Storm Hilary Discussion Number 9 NWS National Hurricane Center Miami FL EP092017 1000 AM CDT Sun Jul 23 2017 Visible imagery indicates that Hilary is becoming better organized. A small central dense overcast has formed, along with a large curved band in the northern semicircle of the cyclone. The initial wind speed is set to 40 kt, a blend of the latest TAFB/SAB estimates. Hilary could be on the verge of starting its long-anticipated significant strengthening period. A 1059 UTC SSMIS microwave pass indicates more inner-core structure with the storm, which suggests that Hilary will be able to take advantage of the nearby conducive atmospheric and oceanic conditions. The SHIPS guidance is also indicating relatively high chances of rapid intensification, roughly a 50/50 chance during the next 48 hours. Given the factors above, the NHC forecast is raised from the previous one, best in line with a blend of the HWRF/DSHIP/HFIP corrected consensus models. An increase in northerly shear, possibly enhanced by outflow from TS Irwin, should cause some weakening late in the period, along with more marginal SSTs. Hilary is moving slower now to the west-northwest at about 9 kt. A ridge over Mexico should steer Hilary in that general direction for the next several days, at various speeds due to the strength of the ridge. Later in the period, there is a possibility of some binary interaction with Irwin, which adds some uncertainty to the forecast. Overall, there hasn't been a lot of change to the model guidance, and the latest NHC track prediction stays relatively close to the previous forecast and the consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 12.7N 102.3W 40 KT 45 MPH 12H 24/0000Z 13.1N 103.5W 50 KT 60 MPH 24H 24/1200Z 13.8N 104.8W 65 KT 75 MPH 36H 25/0000Z 14.6N 106.2W 75 KT 85 MPH 48H 25/1200Z 15.4N 107.9W 90 KT 105 MPH 72H 26/1200Z 16.5N 112.0W 100 KT 115 MPH 96H 27/1200Z 17.6N 115.8W 90 KT 105 MPH 120H 28/1200Z 19.0N 119.0W 85 KT 100 MPH $$ Forecaster Blake