Sandra (Eastern Pacific)

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GOES-West image of Sandra
NOAA’s GOES-West satellite captured this image of Hurricane Sandra off the coast of western Mexico on Nov. 27 at 1400 UTC (9 a.m. EST).
Credits: NASA/NOAA GOES Project

Hurricane Sandra broke a record in the hurricane history books as the latest major hurricane on record in the Eastern Pacific Ocean. On November 26, 2015 at 0706 UTC (2:06 a.m. EST). Sandra had winds of 125 knots (144 mph) at that time making it a category three on the Saffir-Simpson hurricane wind scale. On Nov. 27 NOAA’s GOES-West satellite captured an image of Sandra, although now a Category 2 hurricane continues its approach to landfall in Western Mexico.

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On Nov. 27, the Government of Mexico issued a Tropical Storm Warning for the coast of mainland Mexico from Altata to San Blas and for Las Islas Marias. NOAA’s GOES-West satellite captured an image of Hurricane Sandra off the coast of western Mexico on Nov. 27 at 1400 UTC (9 a.m. EST). The image showed a band of thunderstorms wrapping into the low-level center from the south of the center. Clouds associated with Sandra were covering coastal areas of western Mexico just south of Baja California.

Where is Sandra?

At 10 a.m. EST (1500 UTC) on Nov. 27, the center of Hurricane Sandra was located near latitude 19.6 North, longitude 108.4 West. That put the center about 185 miles (295 km) southwest of Las Islas Marias, Mexico, and about 280 miles (450 km) south-southwest of Mazatlan, Mexico. Sandra was moving toward the north-northeast near 12 mph (19 kph), and the National Hurricane Center expects that motion to continue over the next day to day and a half. On the forecast track, the center of Sandra is forecast to pass west of Las Islas Marias during the evening on Nov. 27 and make landfall within the warning area early Saturday, Nov. 28.

 

Maximum sustained winds are near 100 mph (155 kph) with higher gusts. Hurricane force winds extend outward up to 35 miles (55 km) from the center and tropical storm force winds extend outward up to 160 miles (260 km). The estimated minimum central pressure is 972 millibars.

Rainfall Expected

Sandra is expected to produce total rainfall accumulations of 1 to 3 inches over the southern portions of the Mexican state of Baja California Sur. Rainfall totals of 4 to 6 inches with isolated maximum amounts of 10 inches are possible across the Mexican states of Sinaloa, Nayarit, northwest Jalisco, western Durango and southern Chihuahua. This rainfall may produce life threatening flash flood and mudslides.

Tropical Storm Force Winds

Tropical storm conditions are expected to reach Las Islas Marias later today, Nov. 27 and reach the coast of mainland Mexico within the warning area this evening.

Rapid Weakening Expected

Hurricane Sandra is expected to weaken quickly as it approaches the coast of western Mexico because wind shear is expected to increase to as much as 40 to 45 knots (46 to 51.7 mph/74 to 83.3 kph). This should result in the low-level circulation of Sandra decoupling from the mid-level circulation before it reaches the coast. A tropical cyclone is like a stack of rotating tires. If one of the tires is pushed out of the stack, the rotation becomes wobbly, weaker and slower. That’s what vertical wind shear does to different layers of a tropical cyclone.

Rapid weakening is forecast during the next 48 hours, and Sandra is forecast to weaken to a tropical storm by Friday night, Nov. 27 and become a remnant low and dissipate after moving inland over Mexico on Saturday, Nov. 28. For updated forecasts, visit the National Hurricane Center website: www.nhc.noaa.gov.

Rob Gutro
NASA’s Goddard Space Flight Center

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