sentences:  Late on August 2, the system attained winds of 135 mph (215 km/h), making it a Category 4 storm.During the afternoon of August 3, Guillermo nearly attained Category 5 intensity as it reached its initial peak intensity with winds of 155 mph (250 km/h) along with a barometric pressure estimated at 925 mbar (hPa; 27.32 inHg).A brief period of weakening took place later that day before further strengthening ensued.