On August 10, the
National Hurricane Center (NHC) began monitoring a westward moving
tropical wave emerging off the west coast of Africa, centered along
16°W. Accompanied by disorganized
convective activity,
development, if any, was expected to be slow. A broad
area of low pressure subsequently formed within the wave about halfway between Africa and the
Cape Verde Islands. Embedded within an elongated
trough, the weak system struggled to organize and convection soon diminished. Interaction with a
monsoon trough reinvigorated shower and thunderstorm activity on August 11 across a large area southwest of the Cape Verde Islands, but the surface low had dissipated by this time. Development was no longer expected over the following days as dry air created a hostile area for storm organization. The wave continued westward across the Atlantic and entered the Caribbean on August 16. Subsequent interactions with South America and an
upper-level trough inhibited improvement of the system. By the next day, the wave was located over Panama, and the NHC upgraded the potential for development to 60%. The wave crossed into the eastern Pacific with accompanying convection, developing a low-pressure area on August 19. Conditions were favorable for further development, and the thunderstorms increased and became better organized on August 20. After an increase in
rainbands and
outflow around the well-defined center, the NHC classified the system as Tropical Depression Thirteen-E early on August 22 about 370 mi (595 km) south-southeast of
Acapulco, Mexico. A strong
ridge over the southern United States, later expanding into northern Mexico, steered the system on a west-northwest course throughout its existence as a tropical cyclone. The storm very quickly organized, developing a
central dense overcast consisting of intense convection; this was aided by warm
water temperatures and low
wind shear. On August 23, the NHC upgraded Marie to hurricane status, and an
eye began forming later that day. On the next day, as the storm
rapidly intensified, the eye became much more distinct and was surrounded by a powerful eyewall. During this phase the storm wobbled, shifting due west before resuming its previous motion. At 18:00
UTC on August 24, Marie attained
Category 5 status on the Saffir–Simpson hurricane wind scale, the first such Pacific hurricane since
Celia in 2010. At its peak, Marie was a large hurricane with tropical storm-force winds covering an area 575 mi (925 km) across. Shortly after Marie attained peak intensity, the convection weakened due to an
eyewall replacement cycle, in which an outer eye formed. The storm also weakened due to gradually decreasing water temperatures. By early on August 26, the eye became much less defined. The double eye feature persisted through that day, although the outer eyewall opened up as thunderstorms weakened further. Late on August 27, Marie weakened to tropical storm status, by which time the circulation became exposed from the convection. A strengthening ridge near
California caused the storm to accelerate more to the west-northwest, into an area of cooler waters and dry air. Failing to produce any additional convection, Marie degenerated into a remnant low late on August 28. Turning west and later west-southwest within a weak easterly flow, Marie slowly moved across the open Pacific while remaining a broad, weak cyclone. The former cyclone eventually lost a well-defined center and dissipated on September 2, about 1,200 mi (1,950 km) northeast of
Hawaii. ==Preparations and impacts==