000 WTPZ42 KNHC 150241 TCDEP2 Tropical Storm Blas Discussion Number 4 NWS National Hurricane Center Miami FL EP022022 1000 PM CDT Tue Jun 14 2022 Tropical Storm Blas has maintained a well-defined structure this evening, with satellite images indicating prominent convective banding. Deep convection has also significantly increased near the circulation center during the past few hours, suggesting that an increase in the storm's intensity is imminent. At this time, Dvorak T-numbers from both TAFB and SAB remain at 3.0, so the initial intensity is held at 45 kt for this advisory. Blas is expected to strengthen during the next couple of days, as the large-scale environment is forecast to remain conducive for continued development. The cyclone is forecast to reach hurricane strength tomorrow while remaining offshore of southwestern Mexico. Later in the week, easterly shear is expected to increase in association with an upper-level anticyclone building over Mexico, and Blas will begin to traverse cooler waters. These large-scale factors are expected to result in Blas weakening by this weekend. The intensity forecast is higher than the consensus aids and lower than HWRF, in line with the prior NHC forecast. The initial motion is slightly west of north, or 350/4 kt, and Blas is forecast to turn leftward and accelerate northwestward in the next 12-24 hours followed by a west-northwestward motion. A west-northwestward motion on the south side of a mid-level ridge should continue into the weekend. The official track forecast is very close to the prior NHC prediction and in good agreement with the consensus track aids. While Blas is expected to remain off the coast of Mexico, the associated swells are expected to affect portions of the coast of southwestern Mexico starting tonight. FORECAST POSITIONS AND MAX WINDS INIT 15/0300Z 15.3N 102.3W 45 KT 50 MPH 12H 15/1200Z 15.4N 102.7W 60 KT 70 MPH 24H 16/0000Z 15.7N 103.4W 70 KT 80 MPH 36H 16/1200Z 16.2N 104.7W 80 KT 90 MPH 48H 17/0000Z 16.8N 106.3W 75 KT 85 MPH 60H 17/1200Z 17.4N 108.3W 70 KT 80 MPH 72H 18/0000Z 17.9N 110.1W 60 KT 70 MPH 96H 19/0000Z 18.8N 112.5W 45 KT 50 MPH 120H 20/0000Z 19.2N 114.5W 35 KT 40 MPH $$ Forecaster Pasch/Hogsett