A tropical wave crossed Central America with widespread showers and thunderstorms on August 12th. The system organized into a broad low
pressure area on the 14th south of Mexico and northwest Central America while moving westward within a favorable upper level environment. By
the morning of of the 16th, a well-defined circulation existed along with prominent rain bands which led to the system being upgraded to
Tropical Storm Hilary. The system quickly strengthened into a hurricane by the morning of the 17th to the southwest of Manzanillo while moving
west-northwest. By the night of the 17th, Hilary had become a major hurricane that was turning to the north-northwest south of the Baja California
peninsula due to an upper level trough offshore the West Coast of the United States. Hilary began to move into cooler waters, increased vertical
wind shear, and began to interact with land on the 19th. Hilary's center moved near Punta Eugenia on the morning of the 19th before weakening
back to a tropical storm and making another landfall in San Quintin, Baja California late on the morning of the 20th. Moving over the state of
Baja California led to additional weakening, but Hilary moved into southern California, albeit briefly, that afternoon. Moving barely back offshore
near San Diego, Hilary made its final landfall on the evening of the 20th before moving up the east side of the Sierra Nevada that night, and into
western Nevada as a post-tropical cyclone/remnant low on the morning of the 21st. Its center moved through southeast Oregon and southern Idaho
dissipating as a surface low that afternoon. Its circulation aloft progressed into southwest Canada soon thereafter.
The graphics below show the storm total rainfall for Hilary, which used rain gage information from National Weather Service River Forecast
Centers, xMACIS2, National Weather Service Forecast Offices, and CoCoRAHS.
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