ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM Tropical Storm Pilar Discussion Number 20 NWS National Hurricane Center Miami FL EP192023 1000 AM CDT Thu Nov 02 2023 Pilar continues to have a burst of convection near the low-level center this morning. There have been a few microwave passes this morning, which depict the overall pulsing nature of the convective structure of Pilar. The satellite intensity estimates have decreased slightly this cycle. Given the nature of the pulsing convective pattern, the initial intensity leans toward the Dvorak CI-numbers, which were 3.0 and 2.5 from TAFB and SAB, respectively. This supports keeping the initial intensity steady at 45 kt, but this could be a little generous. Pilar continues to accelerate westward this morning at an estimated motion of 260/13 kt. A strengthening mid-level ridge is building to the north and northeast of Pilar, which will steer the system west-southwestward the next few days. A shortwave trough is forecast to move in from the northwest and weaken the mid-level ridge late this weekend. This will result in Pilar slowing down and turning west to west-northwest early next week. The model guidance is in fairly good agreement with this scenario, with the main difference among the models being along-track with the forward speed of Pilar. The NHC forecast is slightly faster than the previous, and lies between the simple and corrected consensus aids. The near term intensity forecast is a little tricky given the pulsing convective nature of Pilar and the interaction with strong low-level northerly winds associated with an ongoing Gulf of Tehuantepec gap wind event. The gap wind flow could introduce some drier air into Pilar's circulation, which may briefly disrupt its convective organization. Later this weekend, the system is forecast to move over warm sea surface temperatures with weak to moderate vertical wind shear. There is some spread in the intensity guidance between 36-72h with some of the hurricane regional models showing strengthening, while some of the global models show little change in intensity. Given the favorable parameters and the guidance trends, the NHC intensity forecast is slightly higher than the previous at these time ranges, but still below the HWRF, HAFS-A and HCCA corrected consensus. Towards the end of the forecast period, Pilar will encounter a less favorable environment with increasing southwesterly shear and drier air. Given the small size of Pilar, intensity fluctuations are possible throughout the forecast period. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 11.9N 95.2W 45 KT 50 MPH 12H 03/0000Z 11.2N 97.7W 45 KT 50 MPH 24H 03/1200Z 10.5N 100.9W 40 KT 45 MPH 36H 04/0000Z 10.1N 104.0W 40 KT 45 MPH 48H 04/1200Z 10.2N 106.8W 45 KT 50 MPH 60H 05/0000Z 10.5N 109.2W 45 KT 50 MPH 72H 05/1200Z 10.9N 111.3W 45 KT 50 MPH 96H 06/1200Z 11.9N 114.5W 40 KT 45 MPH 120H 07/1200Z 13.1N 117.3W 35 KT 40 MPH $$ Forecaster Kelly NNNN