000 WTNT44 KNHC 112053 TCDAT4 Tropical Storm Karl Discussion Number 1 NWS National Hurricane Center Miami FL AL142022 400 PM CDT Tue Oct 11 2022 Tropical Storm Karl has formed over the Bay of Campeche. Aircraft and scatterometer data show a closed circulation with a relatively large radius of maximum winds and a broad area of light and variable winds near the center. The Air Force Hurricane Hunter reconnaissance aircraft found believable SFMR wind speeds of 35 kt and flight-level winds up to 46 kt while investigating the system. The scatterometer data also showed a large area of 30-35 kt winds to the north of the center. The initial intensity is set to 35 kt based on these data. Karl is moving slowly northwestward at an estimated 5 kt. The storm is embedded in a high pressure system, and this motion is expected to continue for the next day or so. Thereafter, the ridge is likely to build westward and steer the cyclone southwestward into the coast of Mexico in a few days. The official forecast is close to the consensus guidance, though this is an uncertain forecast due to the spread in the forecast track models near landfall. Atmospheric and oceanic conditions are forecast to be conducive for Karl during the next day or so. This should allow Karl to strengthen before global models suggest the vertical wind shear increases and causes gradual weakening before landfall. Rapid decay is expected once the storm moves inland due to the mountainous terrain. The NHC intensity forecast peaks at 45 kt in 24 h which is close to the SHIPS guidance, though all of guidance is clustered near this value. Key Messages: 1. Heavy rainfall could produce flash flooding in the Isthmus of Tehuantepec and in the southern Sierra Madre Oriental mountains and adjacent coastal areas with possible mudslides in areas of higher terrain. 2. Tropical storm conditions are possible in the watch area in Mexico starting Thursday. FORECAST POSITIONS AND MAX WINDS INIT 11/2100Z 19.6N 94.4W 35 KT 40 MPH 12H 12/0600Z 20.3N 94.9W 40 KT 45 MPH 24H 12/1800Z 21.1N 95.3W 45 KT 50 MPH 36H 13/0600Z 21.2N 96.0W 45 KT 50 MPH 48H 13/1800Z 20.7N 96.3W 40 KT 45 MPH 60H 14/0600Z 20.2N 96.6W 35 KT 40 MPH 72H 14/1800Z 19.9N 97.0W 25 KT 30 MPH...INLAND 96H 15/1800Z...DISSIPATED $$ Forecaster Bucci/Blake