767 WTPZ41 KNHC 300844 TCDEP1 Hurricane Agatha Discussion Number 10 NWS National Hurricane Center Miami FL EP012022 400 AM CDT Mon May 30 2022 Agatha's satellite presentation has remained fairly steady state since last evening. The center is embedded beneath a compact central dense overcast, but there have been no microwave satellite passes overnight to provide a better view of the hurricane's structure. Dvorak estimates from TAFB and SAB are also steady, remaining at T5.0, so Agatha's initial intensity is being held at what the Air Force Reserve Hurricane Hunter found yesterday--95 kt. A second and final Hurricane Hunter mission is scheduled for later this morning, assuming the center isn't too close to the coast and the plane can navigate a safe distance away from the nearby mountainous terrain. We did receive two ASCAT passes a few hours ago, which indicated that tropical-storm-force winds have begun along the coast of Oaxaca. The scatterometers also helped to refine Agatha's position, and the initial motion remains slowly northeastward, or 055/5 kt. This northeastward motion is expected to continue today, and Agatha's center should cross the coast of Oaxaca within the next 12-18 hours. The center, or Agatha's remnants, should then continue northeastward over the Isthmus of Tehuantepec. There have been no notable shifts in the latest track guidance, thus the new NHC forecast is very similar to the previous one. Agatha has another 12 hours or so to take advantage of warm 29 degree Celsius waters. However, the hurricane doesn't seem to have been able to benefit from the waters during the previous 12 hours, and it's not entirely clear if it will strengthen before landfall. One potential negative influence is the nearby coastal mountains of southern Mexico, which are likely to disrupt the low-level circulation of the relatively small hurricane. Nearly all of the intensity models show Agatha weakening immediately, but the NHC forecast will maintain a steady intensity up until landfall, with rapid weakening occurring once Agatha makes landfall and moves over the rough terrain. This forecast does not preclude the possibility of some intensification before landfall. Dissipation of Agatha's surface circulation over southern Mexico is now expected by 48 hours. Key Messages: 1. Extremely dangerous coastal flooding from storm surge, accompanied by large and destructive waves, is expected near and the east of where Agatha makes landfall. 2. Life-threatening hurricane-force winds are expected in portions of the hurricane warning area in Oaxaca, Mexico, starting midday and continuing through this evening. Tropical storm conditions have already begun along the coast of Oaxaca and will spread eastward within the warning area through today and tonight. 3. Heavy rains associated with Agatha will continue over portions of southern Mexico through Tuesday. This will pose a threat of potentially life-threatening flash flooding and mudslides. FORECAST POSITIONS AND MAX WINDS INIT 30/0900Z 14.8N 97.7W 95 KT 110 MPH 12H 30/1800Z 15.4N 96.8W 95 KT 110 MPH 24H 31/0600Z 16.3N 95.6W 60 KT 70 MPH...INLAND 36H 31/1800Z 16.9N 94.7W 35 KT 40 MPH...INLAND 48H 01/0600Z...DISSIPATED $$ Forecaster Berg