Hurricane Darby (2010)

Hurricane Darby was a tropical cyclone that meandered over the open waters of the eastern Pacific Ocean in late June 2010. The fourth named storm and the second of only two major hurricanes to form during the unusually inactive 2010 Pacific hurricane season, Darby originated from an area of disturbed tropical weather on June 22. It quickly organized, and it peaked as a low-end Category 3 hurricane on the Saffir–Simpson scale on June 25. The remnants of Hurricane Darby brushed Mexico and produced moderate rainfall which worsened flooding caused by Hurricane Alex in the 2010 Atlantic hurricane season.

Meteorological History
On June 20, the National Hurricane Center (NHC) began monitoring an area of disturbed weather to the east of Hurricane Celia as it began to show some signs of organization. This trend continued and environmental conditions were favorable for further development. The NHC noted that tropical cyclogenesis was possible in the region, and on June 22 the system organized into Tropical Depression Five-E as convective activity became slightly more concentrated. By early on June 23, an ASCAT pass pass record winds of 35 mph (just shy of tropical storm intensity), but due to the improved cloud pattern, the NHC upgraded the depression into a tropical storm and received the name Darby. Although it was initially expected to remain a tropical storm, in a favorable environment, Darby began a rapid deepening phase. By the afternoon of June 23, it was a strong tropical storm. Further intensification was predicted, and the NHC forecasted Darby to intensify into a hurricane. Although the rate of intensification slowed overnight; Darby was upgraded into a hurricane early on June 24 because Dvorak classifications, a tool that estimates a tropical cyclones intensity, supported minimal hurricane intensity. At this time, it was located about 235 mi (375 km) south-southwest of Puerto Escondido, Oaxaca.

Continuing to intensify, Darby reached winds of 80 mph as an eye intermediately became visible on IR imagery early on June 25. Later that day, the Darby developed a persistent eye. Based on this, the NHC upgraded Darby into a moderate category 2 hurricane, with winds reaching 105 mph. Darby soon intensified to become the second major hurricane of the season while a ring of very deep convection formed around the hurricane. Darby reached peak winds of 120 mph shortly thereafter, before beginning a weakening phase due to increased Wind Shear from the Outflow of Hurricane Alex. Forecasts called for Darby to weaken, but with the Wind Shear values over the storm rising, Darby weakened quicker than expected. Darby weakened to a Tropical Depression on the 28th, and by the 30th, Darby was no more.

Preparations and Impact
Prior to the arrival of Darby, a green alert was issued for the states of Oaxaca, and Guerrero. Officials there were asked to execute certain procedures and inform the public. A blue alert was issued for the city of Michoacán, Colima. The local civil protection was asked to review emergency caution and check the condition of local shelters. The general public was asked to monitor local weather conditions. and the Weather Service advised sailors and local residents to monitor the hurricane due to the threat of high waves and heavy rain. The hazard alert was raised from moderate to strong. and the storm was forcasted to make a turn inland.

After dissipating, gusty winds reached 25 km/h, and some rainfall was reported in the area. In the southern states of Oaxaca and Guerrero, hundreds of people were evacuated due to flooding caused Atlantic Hurricane Alex and possibly the remnants of Darby. As a result, three people died. Hurricane Darby was the earliest second major hurricane of any season on record, eclipsing Hurricane Daniel in 1978. Due to Darby's intensification into a major hurricane, 2010 became the third season with two major hurricanes in June, after 1978 and 1985. Due to the presence of Tropical Storm Blas, and the two major hurricanes observed in the month of June, the 2010 Pacific hurricane season set the record highest ACE value for the month of June, which was 37.22, eclipsing the former record set in 1984.