000 WTPZ34 KNHC 211735 TCPEP4 BULLETIN Hurricane Willa Intermediate Advisory Number 6A NWS National Hurricane Center Miami FL EP242018 1200 PM MDT Sun Oct 21 2018 ...WILLA CONTINUES TO STRENGTHEN... ...HURRICANE AND TROPICAL STORM WATCHES IN EFFECT FOR PARTS OF THE SOUTHWESTERN COAST OF MEXICO... SUMMARY OF 1200 PM MDT...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...16.8N 106.9W ABOUT 260 MI...420 KM SSW OF CABO CORRIENTES MEXICO MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H PRESENT MOVEMENT...NW OR 325 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...971 MB...28.67 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * San Blas to Mazatlan A Tropical Storm Watch is in effect for... * Playa Perula to San Blas A Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Additional watches may be required for a portion of the coast of mainland Mexico later today, and interests elsewhere along the coasts of west-central and southwestern mainland Mexico should monitor the progress of Willa. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1200 PM MDT (1800 UTC), the center of Hurricane Willa was located near latitude 16.8 North, longitude 106.9 West. Willa is moving toward the northwest near 7 mph (11 km/h), and this general motion is expected to continue today. A turn toward the north-northwest and north is expected by tonight and Monday. Willa is expected to accelerate toward the north-northeast and approach the southwestern coast of mainland Mexico by late Tuesday. Maximum sustained winds have increased to near 105 mph (165 km/h) with higher gusts. Steady to rapid strengthening is forecast during the next day or so, and Willa is expected to become a major hurricane by Monday morning. Hurricane-force winds extend outward up to 15 miles (30 km) from the center and tropical-storm-force winds extend outward up to 60 miles (95 km). The estimated minimum central pressure is 971 mb (28.67 inches). HAZARDS AFFECTING LAND ---------------------- STORM SURGE: A dangerous storm surge and large and destructive waves are possible along portions of the coast of southwestern Mexico by Tuesday or Tuesday night. WIND: Hurricane conditions are possible within the hurricane watch area by late Tuesday, with tropical storm conditions possible by Tuesday morning. Tropical storm conditions are possible within the tropical storm watch area by early Tuesday. RAINFALL: Willa is expected to produce storm total rainfall accumulations of 5 to 10 inches, with local amounts to 15 inches, across portions of western Jalisco, western Nayarit, and southern Sinaloa in Mexico. This rainfall would cause life-threatening flash flooding and landslides. Farther inland, Willa is expected to produce 2 to 4 inch amounts across portions of Zacateca, Durango, southeast Chihuahua, and Coahuila in Mexico, with local amounts to 6 inches possible. This rainfall could also cause life-threatening flash flooding. SURF: Swells generated by Willa should begin to affect portions of the coast of southwestern and west-central Mexico by Monday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 300 PM MDT. $$ Forecaster Brown