714 WTPZ35 KNHC 300839 TCPEP5 BULLETIN Hurricane Rosa Advisory Number 21 NWS National Hurricane Center Miami FL EP202018 200 AM PDT Sun Sep 30 2018 ...ROSA WEAKENING AS IT MOVES NORTHWARD OVER COLDER WATERS... ...FLOODING RAINS EXPECTED ACROSS NORTHWESTERN MEXICO AND THE SOUTHWESTERN UNITED STATES OVER THE NEXT FEW DAYS... SUMMARY OF 200 AM PDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...23.3N 118.8W ABOUT 385 MI...625 KM SW OF PUNTA EUGENIA MEXICO ABOUT 585 MI...940 KM SSW OF SAN FELIPE MEXICO MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H PRESENT MOVEMENT...N OR 5 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * West coast of the Baja California peninsula from Punta Abreojos to Cabo San Quintin A Tropical Storm Watch is in effect for... * East coast of the Baja California peninsula from Bahia de los Angeles to San Felipe A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere in the northern and central Baja California peninsula and northwestern Sonora should monitor the progress of Rosa. Additional watches or warnings may be required later this morning. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 200 AM PDT (0900 UTC), the center of Hurricane Rosa was located near latitude 23.3 North, longitude 118.8 West. Rosa is moving toward the north near 12 mph (19 km/h) and this motion is expected to continue through this morning. A north-northeastward motion is expected to begin on Monday afternoon and continue through Tuesday. On the forecast track, the center of Rosa will approach the central and northern Baja California peninsula on Monday. Rosa's remnants will then move quickly across the Desert Southwest on Tuesday. Maximum sustained winds have decreased to near 85 mph (140 km/h) with higher gusts. Additional weakening is forecast during the next couple of days, and Rosa is expected to become a tropical storm by this evening. Hurricane-force winds extend outward up to 30 miles (45 km) from the center and tropical-storm-force winds extend outward up to 150 miles (240 km). The estimated minimum central pressure is 975 mb (28.80 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Over the next few days, Rosa is expected to produce the following total rainfall accumulations: Baja California and northwestern Sonora: 3 to 6 inches, isolated 10 inches. The Mogollon Rim of Arizona: 2 to 4 inches, isolated 6 inches. Rest of the Desert Southwest, Central Rockies, and Great Basin: 1 to 2 inches, isolated 4 inches. These rainfall amounts would produce life-threatening flash flooding and dangerous debris flows in the deserts, as well as landslides in mountainous terrain. WIND: Tropical storm conditions are expected to first reach the coast within the warning area by Monday morning. Tropical storm conditions are possible within the watch area by late Monday. SURF: Swells generated by Rosa will affect portions of the coasts of southwestern Mexico, most of the west coast of the Baja California peninsula, and southern California from today through Tuesday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 500 AM PDT. Next complete advisory at 800 AM PDT. $$ Forecaster Stewart