000 WTPZ42 KNHC 242038 TCDEP2 Hurricane Rick Discussion Number 10 NWS National Hurricane Center Miami FL EP172021 400 PM CDT Sun Oct 24 2021 Rick continues to hold its own, with little change in overall organization over the past 18 to 24 hours. There is still no eye evident in satellite images, and earlier microwave images revealed that the eyewall underneath the cirrus canopy is open on the eastern side. There is a large amount of spread in the various objective and subjective Dvorak intensity estimates, which range from 60 kt to 90 kt. Since Rick does not look any better or worse than 6 hours ago, the difference between these estimates is split down the middle, and the initial advisory intensity remains 75 kt. Based on data from a 1656 UTC ASCAT-B overpass, winds of tropical storm force were only 30 n mi from the coast of southwestern Mexico. A recent ASCAT-B overpass helped to verify the position of the center of Rick, and the system has been moving a little slower and to the right of what was previously thought. The initial motion is therefore set at 360/04 kt. Rick continues to move in the direction of a weakness in the subtropical ridge. Most of the model guidance suggest the ridge may begin to fill in slightly to the northeast of the cyclone as early as tonight, which would cause the hurricane to turn north-northwestward along with a slight increase in forward speed. The only notable change to the NHC track forecast was a slightly slower motion in the short term. Otherwise, the track is very close to the multimodel consensus solutions. Rick has been unable to take advantage of the favorable environment for strengthening over the past 24 hours, and the hurricane is about out of time to intensify any further. The UW-CIMMS shear analysis shows 15 to 20 kt of vertical wind shear between Rick and the coast of Mexico, and 400-700 mb relative humidity of only about 50 percent. Therefore, it is becoming less likely that Rick will undergo any significant strengthening before landfall. The latest NHC intensity forecast is lower than the previous one, but remains on the high end of the guidance. After landfall, the cyclone will weaken rapidly and the system may dissipate sooner than shown in this forecast. Key Messages: 1. Rick is forecast to reach the coast of southern Mexico Monday morning, bringing life-threatening storm surge and dangerous hurricane-force winds within a portion of the Hurricane Warning area from Tecpan de Galeana to Punta San Telmo. Residents in this area should follow any advice given by local officials. 2. Rick is expected to bring tropical storm conditions to portions of the southern and southwestern coasts of Mexico beginning within the next couple of hours from east of Tecpan de Galeana to Acapulco, and by Monday morning from west of Punta San Telmo to Manzanillo, where a Tropical Storm Warning is in effect. 3. Heavy rains associated with Rick are expected to spread across the Mexican states of Guerrero and Michoacan through tonight, and could persist through Tuesday. This rainfall will likely produce flash flooding and mudslides. FORECAST POSITIONS AND MAX WINDS INIT 24/2100Z 16.3N 101.7W 75 KT 85 MPH 12H 25/0600Z 17.1N 101.9W 80 KT 90 MPH...NEAR COAST 24H 25/1800Z 18.4N 102.6W 50 KT 60 MPH...INLAND 36H 26/0600Z 19.6N 103.4W 25 KT 30 MPH...INLAND 48H 26/1800Z...DISSIPATED $$ Forecaster Latto/Pasch