Hurricane Bud weakened significantly on Tuesday, but it prompted the issuance of a Tropical Storm Watch for the southern portion of Baja California. At 11:00 p.m. EDT on Tuesday the center of Hurricane Bud was located at latitude 18.7°N and longitude 108.6°W which put it about 300 miles (485 km) south-southeast of Cabo San Lucas, Mexico. Bud was moving toward the north-northwest at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 90 m.p.h. (150 km/h) and there were wind gusts to 105 m.p.h. (170 km/h). The minimum surface pressure was 973 mb. The government of Mexico issued a Tropical Storm Watch for the portion of the coast from Santa Fe to La Paz, Mexico including Cabo San Lucas.
Hurricane Bud weakened to a Category 1 hurricane on the Saffir-Simpson Scale on Tuesday. The center of Hurricane Bud was over water where the Sea Surface Temperature was near 27°C, but much of the northern half of the circulation was over cooler water. The slow movement of Bud may have also allowed the winds to mix cooler water to the surface. Thunderstorms were not as tall and the bands in the northern half of the circulation consisted primarily of showers and low clouds. The stronger thunderstorms were occurring mainly south and east of the center of Hurricane Bud.
Hurricane Bud is forecast to spin down slowly during the next several days. Cooler water at the surface of the ocean is not likely to supply sufficient energy to maintain the circulation. The upper level winds are weak and there is little vertical wind shear, but the lack of shear will be less important than effects of the cooler water. The lack of stronger thunderstorms in the northern half of the circulation will limit the downdrafts that could transport stronger winds to the surface. Hurricane Bud could weaken to a tropical storm on Wednesday if new thunderstorms do not form in the core of the circulation.
A ridge in the middle troposphere over the southwestern U.S. almost blocked the forward motion of Hurricane Bud on Tuesday. Bud moved slowly toward the north-northwest. A slow motion toward the north-northwest is forecast to continue for another 24 to 36 hours. After that time a trough over the Pacific Ocean is forecast to push the ridge eastward. When the trough approaches, stronger southerly winds will steer Bud northward more quickly. On its anticipated track Bud is forecast to approach the southern tip of Baja California in 36 to 48 hours.
Hurricane Bud is likely to be a tropical storm when it nears Baja California. Bud will bring gusty winds, but the bigger risk will be locally heavy rain. Heavy rain falling on steep terrain could cause flash floods. Bud or its remnants could also bring rain to parts of the southwestern U.S.