813 WTPZ41 KNHC 280249 TCDEP1 Tropical Depression One-E Discussion Number 1 NWS National Hurricane Center Miami FL EP012022 1000 PM CDT Fri May 27 2022 The satellite presentation of the low pressure system that the NHC has been monitoring south of the southern coast of Mexico for the past several days has greatly improved this evening. Earlier microwave data and visible satellite imagery showed increased signs of curved convective bands wrapping around the low-level center. More recently, SSMIS microwave data suggest the inner-core structure of the cyclone has improved, and very cold infrared cloud tops have spread over the center. The system has achieved sufficient convective organization to be designated as the first depression of the 2022 Eastern North Pacific hurricane season. The initial intensity is set at 30 kt based on a subjective T2.0/30 kt Dvorak classification from TAFB, although the initial intensity is somewhat uncertain given the lack of recent scatterometer data. The system is moving westward at 265/6 kt, and this general motion is expected to continue for the next 12 h or so. A deep-layer trough is forecast to amplify across the western U.S. this weekend, which will weaken the ridge to the north of the cyclone. This will allow the system to slowly turn northward on Sunday and then move northeastward on Monday as it approaches southern Mexico. The track models generally agree on this scenario, although the GFS is somewhat further east than the rest of the guidance. The official NHC forecast lies toward the center of the guidance envelope, roughly in between the HFIP corrected-consensus approach (HCCA) and the multi-model consensus aids. Sea-surface temperatures greater than 30 deg C, weak deep-layer vertical wind shear, and abundant mid-level moisture are expected to support significant intensification of the cyclone this weekend. In fact, all of the intensity guidance shows steady strengthening during the next few days, and many models including the consensus aids bring the cyclone to hurricane intensity within 48 h. The GFS SHIPS-RII highlights the potential for rapid intensification of this system, with a 52 percent chance of a 35-kt intensification in 24 h. The official NHC intensity forecast shows steady strengthening during the next few days, with the cyclone becoming a hurricane by late Sunday with continued strengthening anticipated as it approaches the coast on Monday. This forecast lies between the IVCN and HCCA aids through 48-60 h, then falls on the higher end of the guidance at 72 h as the official forecast track remains just off the coast. Tropical Storm and/or Hurricane Watches will likely be required Saturday morning for portions of the coast of southern Mexico, and interests in this region should closely monitor the progress of this system. Key Messages: 1. There is an increasing risk of tropical-storm-force and hurricane-force winds along portions of the southern coast of Mexico early next week, and Tropical Storm or Hurricane Watches will likely be required Saturday morning. Interests in this area should closely monitor the progress of this system and updates to the forecast. 2. Heavy rains associated with Tropical Depression One-E will develop over portions of southern Mexico this weekend and continue through Tuesday. This will pose a threat of flash flooding and mudslides. For more information, see products from your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 28/0300Z 12.8N 97.9W 30 KT 35 MPH 12H 28/1200Z 12.8N 98.6W 40 KT 45 MPH 24H 29/0000Z 13.2N 98.9W 50 KT 60 MPH 36H 29/1200Z 13.7N 98.9W 60 KT 70 MPH 48H 30/0000Z 14.2N 98.7W 70 KT 80 MPH 60H 30/1200Z 14.7N 98.1W 80 KT 90 MPH 72H 31/0000Z 15.7N 96.9W 80 KT 90 MPH...NEAR THE COAST 96H 01/0000Z 17.2N 95.1W 30 KT 35 MPH...INLAND 120H 02/0000Z...DISSIPATED $$ Forecaster Reinhart