ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Tropical Depression Three Discussion Number 1 NWS National Hurricane Center Miami FL AL032020 400 PM CDT Mon Jun 01 2020 Recent satellite data and surface observations from Mexico show that the circulation associated with the area of disturbed weather over the Yucatan peninsula has become better defined during the past several hours, and that the center has moved over the eastern portion of the Bay of Campeche. Although the deep convection has waned somewhat, there is evidence of banding in both visible satellite imagery and recent radar data from Sabancuy, Mexico. Based on these data, advisories are being issued on a tropical depression. The initial intensity is set at 25 kt, which is in agreement with earlier ASCAT data. The depression will be moving over the warm waters over the Bay of Campeche and upper-level winds are forecast to be generally conducive for strengthening during the next couple of days. The NHC forecast is in line with much of the intensity guidance and calls for the system to become a tropical storm in 12 to 24 hours, with some additional strengthening predicted through 48 hours while the system remains over the southern Bay of Campeche. After that time, the system's intensity will depend on how much it interacts with land. Although the latest runs of the GFS and ECMWF models take the cyclone inland over southern Mexico, the NHC forecast keeps it just offshore and shows the cyclone maintaining tropical storm strength. Later in the period, the guidance suggests that the system could strengthen over the south-central Gulf of Mexico, but the latter portion of the intensity forecast is of low confidence. The depression is moving west-northwestward or 290/6 kt. The system has been moving cyclonically around a larger gyre over Central America during the past couple of days, and while it remains embedded within the gyre it is forecast to turn west-southwestward, and then southward at a slower forward speed over the next couple of days. On this track, the cyclone is expected to move near the southern Bay of Campeche coast during the next day or two, and confidence it that portion of the track forecast is high. After that time, two distinct scenarios emerges. The first is that the cyclone continues moving southward and weakens or dissipates over the rugged terrain over southern Mexico. The latest runs of the ECMWF and GFS favor that scenario. In this scenario, both models show a new system developing near the south-central Gulf of Mexico from another vorticity center that rotates around the larger gyre. The second scenario, favored by the UKMET and some EC ensemble members, is for the depression to eject north-northeast moving into the central Gulf of Mexico by day 5. The NHC forecast favors the latter, but it is certainly possible that this tropical cyclone will move inland and dissipates and a new cyclone formation occurs later this week. The latter portion of both the track and intensity forecast are of quite low confidence. Key Messages: 1. The depression is expected to bring heavy rainfall to portions of southern Mexico, Guatemala, Honduras and El Salvador, which could cause life-threatening flash flooding and mudslides. Refer to products from your local weather office for more information. 2. Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect. 3. The system is forecast to begin moving northward across the Gulf of Mexico later this week. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 19.6N 91.2W 25 KT 30 MPH 12H 02/0600Z 19.8N 92.3W 30 KT 35 MPH 24H 02/1800Z 19.5N 92.8W 35 KT 40 MPH 36H 03/0600Z 19.2N 93.0W 40 KT 45 MPH 48H 03/1800Z 18.8N 93.2W 45 KT 50 MPH 60H 04/0600Z 18.8N 93.2W 45 KT 50 MPH 72H 04/1800Z 18.8N 93.2W 45 KT 50 MPH 96H 05/1800Z 19.0N 92.8W 45 KT 50 MPH 120H 06/1800Z 23.0N 91.0W 50 KT 60 MPH $$ Forecaster Brown NNNN