Dolores (2009)

A tropical wave that moved off Africa on 1 July crossed Central America into the eastern Pacific on 8 July and gradually organized. A broad low formed several hundred miles south of Acapulco on 11 July, and a tropical depression developed near 0000 UTC 15 July about 605 nautical miles west-southwest of Manzanillo, Mexico. The system moved generally northwestward and became Tropical Storm Dolores about 12 hours after formation. Dolores weakened to a gale-force low by about 1800 UTC 16 July and its remnants continued northwestward until dissipating around 0600 UTC 20 July about 865 nautical miles west-southwest of Los Angeles, California.

Dolores did not make landfall on the Mexican mainland. The only land observation of note came from Clarion Island, where a wind gust of 39 kt (about 45 mph) was reported on 16 July. No watches or warnings were required or issued for coastal areas.

The storm’s peak intensity was 50 knots (about 58 mph) near 0000 UTC 16 July, with a minimum central pressure estimated at 997 mb. At peak it was a moderate tropical storm (below hurricane strength). The QuikSCAT satellite provided the primary data supporting the peak wind estimate.

There were no reports of storm surge or significant rainfall associated with Dolores in populated areas; the report only notes the Clarion Island observation and no coastal surge measurements. No rainfall totals or surge heights for Mexican cities or counties are given in the official report.

No damage or casualties were reported. The regions most affected were limited to open ocean and Clarion Island; Mexican coastal areas did not report impacts.

Forecasts recognized the potential for development well in advance: the system’s development was first noted on 11 July and was given a high chance of formation by 13 July. Official track errors for Dolores were larger than recent averages at 12–24 hours but intensity forecasts were generally better than five-year means, though the storm was short-lived so the sample of forecasts was small.