Blas (2010)

A tropical depression formed early on 17 June 2010 about 265 nautical miles south-southwest of Manzanillo, Mexico, after a tropical wave crossed Central America. The system strengthened to Tropical Storm Blas later that day and moved northwest then west-northwest under the influence of a ridge. Blas lasted as a tropical cyclone from 17 June until it weakened to a remnant low on 21 June and the remnant low dissipated by 23 June.

Blas remained over open water and did not make any landfalls on the Mexican coast or elsewhere. The cyclone moved generally away from land, degenerating to a tropical depression around 0000 UTC 21 June and to a remnant low by 1800 UTC that day about 620 nautical miles west-southwest of the southern tip of Baja California.

The storm reached its maximum intensity on 19 June, with peak sustained winds of 55 knots (about 63 mph) and a minimum central pressure of 994 mb. At peak, Blas was a moderate tropical storm (below hurricane strength).

Storm surge and heavy rainfall impacts were minimal because Blas remained well offshore. No specific storm surge measurements or significant rainfall totals at named cities or counties were reported in the post-storm analysis.

There were no reports of damage or casualties associated with Blas. The areas most affected were open-ocean interests, such as ships; a Maersk Dhahran reported winds near 40 kt and a pressure of 1002 mb on 17 June, which helped confirm tropical-storm strength.

Forecast notes: the system’s development was anticipated several days in advance but with low to moderate confidence, and the exact timing of genesis was not well predicted. Official track forecasts performed generally better than many individual models at short lead times, and intensity forecasts were competitive with guidance, especially beyond 24 hours.