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#1003235 (Received by flhurricane at: 10:37 PM 01.Jun.2020) TCDAT3 Tropical Depression Three Discussion Number 2 NWS National Hurricane Center Miami FL AL032020 1000 PM CDT Mon Jun 01 2020 Satellite imagery, along with radar and surface data from Mexico, indicate that the depression has changed little in organization or strength since the previous advisory. There are a couple of small clusters of convection near the center, while the more concentrated convection is occurring in ragged bands well removed from the center. The initial intensity remains 25 kt based on the surface data and continuity from the previous advisory. The initial motion is now westward or 270/6. The evolution of this system during the next several days remains quite uncertain. The Canadian and UKMET models forecast the cyclone to make a slow counter-clockwise loop inside a larger gyre over Central America during the next 2-3 days, with the center moving near the coast of the Bay of Campeche. This would be followed by a more northward motion with some increase in forward speed as a mid-/upper-level trough develops over the northern Gulf of Mexico. On the other hand, the GFS and ECMWF show the depression turning southward and making landfall over the coast of Mexico in the next 24-36 h, followed by dissipation. These two models subsequently develop a second low pressure area northwest of the Yucatan Peninsula at around 120 h due to the interaction of the aforementioned gyre and trough. The new forecast track follows the previous forecast in showing TD-3 as being the system that moves northward across the Gulf. However, the new track brings the center closer to the coast of Mexico and is slower to move it northward than in the previous advisory. It should be noted, though, that in 5 days there could be a cyclone near the forecast point that is not actually TD-3. In the current track forecast scenario, slow strengthening should occur during the next 24-48 h while the cyclone moves over the warm water of the Bay of Campeche in an environment of light to moderate shear. After time, proximity to the Mexican coast should limit strengthening, and it is possible that the current forecast intensities could be generous. The more northward motion near the end of the forecast period is likely to be accompanied by an increase in southerly shear, so only modest intensification is forecast during that time. Overall, the new intensity forecast is similar to the previous forecast. An alternative intensity forecast scenario is that the cyclone moves far enough inland over Mexico to dissipate completely in less than 5 days as forecast by the GFS and ECMWF. Given the complexity of the situation, both the track and intensity forecasts are currently low confidence. However, either of the current scenarios will result in widespread heavy rains over portions of southern Mexico and Central America. 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 02/0300Z 19.6N 91.9W 25 KT 30 MPH 12H 02/1200Z 19.6N 92.6W 30 KT 35 MPH 24H 03/0000Z 19.2N 92.8W 35 KT 40 MPH 36H 03/1200Z 18.8N 93.0W 40 KT 45 MPH 48H 04/0000Z 18.6N 93.1W 45 KT 50 MPH 60H 04/1200Z 18.5N 93.2W 45 KT 50 MPH 72H 05/0000Z 18.5N 93.0W 45 KT 50 MPH 96H 06/0000Z 19.5N 92.5W 45 KT 50 MPH 120H 07/0000Z 22.0N 91.5W 50 KT 60 MPH $$ Forecaster Beven |